Seaweed Potential as a marine vegetable and other

opportunities

by Barry Lee

January 2008

RIRDC Publication No 08/009 RIRDC Project No CON-9A

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© 2008 Rural Industries Research and Development Corporation. All rights reserved. ISBN 1 74151 598 X ISSN 1440-6845 Seaweed: Potential as a marine vegetable and other opportunities Publication No. 08/009 Project No. CON-9A The information contained in this publication is intended for general use to assist public knowledge and discussion and to help improve the development of sustainable regions. You must not rely on any information contained in this publication without taking specialist advice relevant to your particular circumstances.

While reasonable care has been taken in preparing this publication to ensure that information is true and correct, the Commonwealth of Australia gives no assurance as to the accuracy of any information in this publication.

The Commonwealth of Australia, the Rural Industries Research and Development Corporation (RIRDC), the authors or contributors expressly disclaim, to the maximum extent permitted by law, all responsibility and liability to any person, arising directly or indirectly from any act or omission, or for any consequences of any such act or omission, made in reliance on the contents of this publication, whether or not caused by any negligence on the part of the Commonwealth of Australia, RIRDC, the authors or contributors.

The Commonwealth of Australia does not necessarily endorse the views in this publication.

This publication is copyright. Apart from any use as permitted under the Copyright Act 1968, all other rights are reserved. However, wide dissemination is encouraged. Requests and inquiries concerning reproduction and rights should be addressed to the RIRDC Publications Manager on phone 02 6271 4186 Researcher Contact Details Barry Lee Connectica International PO Box 294 Gymea Australia 2227 Phone: 0418 230393 Fax: 02 9545 2687 Email: barrywlee@ozemail.com.au

In submitting this report, the researcher has agreed to RIRDC publishing this material in its edited form. RIRDC Contact Details Rural Industries Research and Development Corporation Level 2, 15 National Circuit BARTON ACT 2600 PO Box 4776 KINGSTON ACT 2604 Phone: 02 6271 4100 Fax: 02 6272 4199 Email: rirdc@rirdc.gov.au. Web: http://www.rirdc.gov.au Published in January 2008 Printed by Canprint

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Foreword Today in both Asian and western markets, the average consumer unknowingly consumes seaweed-derived products on an almost daily basis. These may range from processed foods, dairy products and cosmetics to garden fertilisers, pharmaceuticals and medicines. With such a breadth of industry applications, this project collates and consolidates information about the world seaweed industry based upon information from the International Seaweed Symposium, Japan (2007) and recent Australian industry research. The report is focussed primarily upon identifying the food research applications for seaweeds and seaweed products, especially those which may be used as marine vegetables. However, this report has also identified other research opportunities or seaweed applications which may provide additional broad benefits for rural Australia. The importance of this report is that it provides baseline statistical and research information for the international and Australian seaweed industry, and identifies the numerous market applications for seaweed products. It will be a useful basis for those contemplating investment or formulating policy and will help to inform RIRDC as it plans its research and development priorities into the future. This project was funded from RIRDC Core Funds which are provided by the Australian Government. This report, an addition to RIRDC’s diverse range of over 1700 research publications, forms part of our Asian Foods R&D program, which aims to support industry in its drive to develop new products and markets and to gain competitive advantage through productivity in, and achieving price premiums for, Australian production. Most of our publications are available for viewing, downloading or purchasing online through our website: downloads at www.rirdc.gov.au/fullreports/index.html purchases at www.rirdc.gov.au/eshop Peter O’Brien Managing Director Rural Industries Research and Development Corporation

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Acknowledgements Connectica International wishes to acknowledge the assistance and support of the following individuals and organisations with the compilation of this report: Mr Greg Jenkins Challenger TAFA, WA Mr Gavin Partridge Challenger TAFA, WA Mr Bruce Ginbey Challenger TAFA, WA Dr Craig Sanderson Consultant Dr Joe Herbertson Crucible Group (The) Assoc Professor Ravi Fotedar Curtin University Mr Vivek Kumar Curtin University Mr Robert Gott Dept of Primary Industries, Water and Environment Tasmania Mr Andrew Sharman Dept of Primary Industries, Water and Environment Tasmania Mr Paul Garrott Marinova Pty Ltd Dr Helen Fitton Marinova Pty Ltd Mr Derek Cropp Marinova Pty Ltd Professor John West Melbourne University Dr Leon Loftus Melbourne University Professor John Beardall Monash University Professor Michael Borowitzka Murdoch University Dr Geoff Allan NSW Department of Primary Industries Dr Pia Winberg Sustainable Seafood Pty Ltd Dr Gary Ellem University of Newcastle

Abbreviations ABS Australian Bureau of Statistics AUSVEG Australian Vegetable and Potato Growers Federation A$ Australian Dollars CSIRO The Commonwealth Scientific and Industrial Research Organisation FAO Food and Agriculture Organisation HAL Horticulture Australia Limited IAAS Integrated Agri-Aquaculture Systems IMTA Integrated Multi-Trophic Aquaculture ISS International Seaweed Symposium (Japan 2007) $M $ Million NAC National Aquaculture Council NCEFF National Centre of Excellence for Functional Foods NHMRC National Health and Medical Research Council NSW New South Wales OFA Omega-3 Fatty Acids QLD Queensland RIRDC Rural Industries Research and Development Corporation SA South Australia SARDI South Australian Research and Development Institute US$ United States of America Dollars VIC Victoria WA Western Australia

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Contents Foreword .............................................................................................................................................. iii Acknowledgements .............................................................................................................................. iv Abbreviations....................................................................................................................................... iv List of Tables, Figures and Plates ...................................................................................................... vi Executive Summary ...........................................................................................................................vii

What the report is about?..................................................................................................................vii Who is the report targeted at?...........................................................................................................vii Background ......................................................................................................................................vii Aims/Objectives ...............................................................................................................................vii Methods used...................................................................................................................................viii Results/Key findings .......................................................................................................................viii Implications .....................................................................................................................................viii Recommendations ............................................................................................................................xii

1. Introduction ...................................................................................................................................... 1 1.1 Background .................................................................................................................................. 1 1.2 What’s in a Name – Marine Vegetables? ..................................................................................... 1 1.3 The Consumer Today ................................................................................................................... 1 1.4 Objectives..................................................................................................................................... 2 1.5 Method.......................................................................................................................................... 2

2. Seaweeds and Consumers – An Overview...................................................................................... 3 2.1 What are Seaweeds? ..................................................................................................................... 3 2.2 The Global Seaweed Industry ...................................................................................................... 3 2.3 The Australian Seaweed Industry................................................................................................. 4 2.4 Seaweeds and Australian Rural Research .................................................................................... 5

3. Market Uses of Seaweed Products .................................................................................................. 6 3.1 Marine Vegetables for Human Nutrition and Health ................................................................... 6 3.2 Seaweeds as Functional Foods ................................................................................................... 12 3.3 Marine Hydrocolloids for Industrial Foods ................................................................................ 14 3.4 Seaweed Biostimulant Products in Agriculture.......................................................................... 15 3.5 The Value-Adding Role of Seaweed in the Aquaculture Industry ............................................. 16 3.6 Seaweeds, Biofuels and Energy ................................................................................................. 18 3.7 Bioactive and Functional Molecules .......................................................................................... 19

4. Discussion of Results ...................................................................................................................... 21 4.1 Market Applications and Opportunities ..................................................................................... 21 4.2 Strategic Sources of Seaweed in Australia ................................................................................. 24 4.3 Summary .................................................................................................................................... 26

5. Implications..................................................................................................................................... 28 6. Recommendations .......................................................................................................................... 29 7. References (including Websites) ................................................................................................... 31

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List of Tables, Figures and Plates Table 1............................................................................................................................................ xi Summary of Market and Research Drivers for Marine Vegetable and Seaweed Applications...... xi Figure 1............................................................................................................................................ 4 Australian Seaweed Imports 2002-2007 ......................................................................................... 4 Table 2............................................................................................................................................. 5 Seaweed Related RIRDC Projects................................................................................................... 5 Plate 1 .............................................................................................................................................. 6 Pink Dunaliella Salina within sea salt............................................................................................. 6 Plate 2 .............................................................................................................................................. 7 Nori or Purple Laver Sheets ............................................................................................................ 7 Plate 3 .............................................................................................................................................. 8 Sea Lettuce (Ulva sp) ...................................................................................................................... 8 Plate 4 .............................................................................................................................................. 9 Kombu and the ‘World of Umami’ Taste........................................................................................ 9 Plate 5 ............................................................................................................................................ 10 Chuka Wakame Salad ................................................................................................................... 10 Plate 6 ............................................................................................................................................ 10 Retail Packs of Hijiki, Kombu, Nori and Wakame ....................................................................... 10 Table 3........................................................................................................................................... 11 Examples of Seaweed Food Applications ..................................................................................... 11 Plate 7 ............................................................................................................................................ 19 Fucoidan Health Supplements....................................................................................................... 19 Plate 8 ............................................................................................................................................ 21 Marine ‘Wrap-Up’ Vegetables ...................................................................................................... 21 Plate 9 ............................................................................................................................................ 22 Seaweed Salad............................................................................................................................... 22

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Executive Summary What the report is about? There is a large and diverse array of applications and uses of seaweed products. The industry is estimated to have an annual value of some US$6 billion (McHugh 2003) and the largest share of this is for food products. It is estimated that US$5 billion of this is used in food products for human consumption. The other US$1 billion is largely based upon extracting hydrocolloids from seaweed for use in products such as animal feeds and fertilizers. This report collates and consolidates information about the world seaweed industry based upon information from the International Seaweed Symposium, Japan (2007) and recent Australian industry developments. The report is focussed primarily upon identifying the food research applications for seaweeds and seaweed products, especially those which may be used as marine vegetables. However, this report also identifies other research opportunities or seaweed applications which may provide additional broad benefits for rural Australia. Who is the report targeted at? This report targets researchers and industry groups involved in the production, processing and marketing of seaweed products in a broad range of industries including agriculture, aquaculture, health and pharmaceuticals. Background Seaweed food products enjoy a reputation for being healthy meals and ingredients throughout Asia but western markets are now increasingly appreciating their nutritional qualities. While previously these products may have been regarded as novel and new, consumer perceptions are changing with seaweed products such as seaweed nori rolls and seaweed salads being enjoyed regularly by many western consumers. The report is focussed primarily upon identifying the food research applications for seaweeds and seaweed products, especially those which may be used as marine vegetables. However, this report has also identified other research opportunities or seaweed applications which may provide additional broad benefits for rural Australia. Aims/Objectives This project filters, collates, and consolidates information from the International Seaweed Symposium, Japan and Australian industry research to provide recommendations on: a. The potential market opportunities for 'marine vegetables'. b. The potential, or not, of a role and position of RIRDC in supporting the development of a

'seaweed products' industry. Specifically, the potential for RIRDC investment to add value to areas such as: - Aquaculture industry in inland areas - Biofuels industry - Bioactives industry - Greenhouse industry and environmental management - Export market opportunities

c. Research investment opportunities.

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Methods used Research was based upon desktop research, in-market research interviews with Australian industry and research groups, and the review of conference presentations at the International Seaweed Symposium in Japan during 2007. Results/Key findings In general, there are current and potential market applications for seaweeds as saltwater marine vegetables, functional natural foods and non-food products. There has been limited development and application of seaweeds in freshwater. A major limiting factor for the further development of the saltwater seaweed products in Australia is the ready availability of seaweed supply into existing local markets which are largely supported by imported seaweed products. The Australian seaweed industry is small and localized. The availability of seaweeds is the constraining factor for the growth of the industry. Currently, the Australian market is largely supplied by seaweed food imports with annual import volumes of over 5,000 tonnes in 2006/07 and an approximate value of A$14 million. This implies that there is a significant Australian market opportunity for seaweed products and the potential for import replacement if the Australian industry is commercially competitive. Conversely, this also implies that the opportunity for increased seaweed exports would be limited, especially given the limited availability of seaweed to the Australian industry at present. Table 1 provides a summary of the industry groups and the broad market and research drivers for the seaweed products. The major research driver is the ability to develop a source of seaweed supply from land-based propagation systems. Such systems are the subject of international research and it is important for Australia to either apply existing technologies and systems or develop proprietary alternatives. In either case, the Australian applications must be cost competitive if it is to compete with global suppliers and importers. Other industrial opportunities are identified for research as these have the potential to provide additional benefits to the rural industry. Implications Research to support the development of Australian seaweed resources for Australian food products will be strategically important. Due to commercial, environmental and social pressures, seaweed farming in Australian marine environments is not feasible. Research is needed to develop alternate land-based sources of seaweed. These sources shall provide the opportunity to develop marine vegetable and seaweed products for both the Australian and potentially Asian export markets. Alternate technologies, skills and associated intellectual property should all be evaluated to ensure that the land-based resource will be commercially viable and competitive with the other major world suppliers. Key research issues for RIRDC to review and assess should include:

- Proprietary systems to propagate seaweeds in land-based aquaculture, Integrated Multi-Trophic Aquaculture (IMTA) and aquaponic systems.

- Technologies that enhance the functional value of Australian seaweed for use in foods for nutrition and health.

- Functional value of Australian seaweed for use in other industries including: o Australian biofuel applications o Bioactive and medical applications o Greenhouse industry applications

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The above research issues shall also have the potential to provide significant benefits to the rural industry including:

- Potential for exports of bioactive substances extracted from seaweeds - Potential for rural areas to diversify their land use and income base - Potential usage of seaweed and micro-algae in inland areas for biofuel use - Potential for the utilisation of inland saline areas - Potential to support Greenhouse management strategies - Sustainable management of resources

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Table 1 Summary of Market and Research Drivers for Marine Vegetable and Seaweed Applications

MARKETS FOOD AGRICULTURE ENVIRONMENT HEALTH

KEY CRITERIA

Marine Vegetables

Texturants Animal Feed

Fertilisers Energy and Biofuels

Aquaculture Bioactives for Health and Medicine

Stage of Market - Emerging - Growth - Mature

Emerging

Mature Emerging

Growth

Emerging

Growth

Growth

Primary Market Drivers

Consumer nutrition and health

Low cost production

Commercial feasibility

Commercial feasibility

Commercial feasibility

Commercial & environmental sustainability

Health and medicine

Primary Research Drivers

- Availability of seaweed - Product development

Applications research

Applications research

Applications research

Propagation and yields of seaweed and micro-algae

Propagation of seaweed in land based systems

- Propagation of seaweed in land based systems - Product development

Rural benefits - Commercial

Yes No Yes Yes Yes Yes Yes

Rural benefits - Community

Yes No Yes Yes Yes Yes Yes

Rural benefits - Environment

Yes No Yes Yes Yes Yes Yes

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Recommendations Marine Vegetable Foods for Human Nutrition Compared to other international markets, to date the Australian market has failed to recognise benefits associated with marine vegetable foods. RIRDC should work with co-investors to prioritise investment for the following research. • Strategic research that shall improve the supply of seaweed and micro-algae resources from

land-based systems such as open air Integrated Multi-Trophic Aquaculture (IMTA) and IMTA greenhouse systems. The land-based systems should be in support of novel or growth market opportunities where Australia has a competitive advantage for supply, quality, technology or intellectual property.

• Product development research is required for food products including: o Seaweed salads o Wrap-up vegetables o Agar gels

Health and Functional Foods Compared to other international markets, to date the Australian market has failed to recognise health and functional food benefits associated with seaweed products. RIRDC should work with co-investors to prioritise investment for the following research. • Support strategic research that will improve the supply of seaweed and micro-algae resources

from land-based systems. • Subject to a concurrent study by the National Centre of Excellence for Functional Foods,

product development research to develop health food products which utilise the functional qualities of seaweeds and/or micro-algae.

Agriculture The Australian agricultural industry does not fully understand the benefits associated with the use of seaweed fertilisers and animal feeds. RIRDC should work with co-investors to prioritise investment for the following research. • Research into seaweed fertiliser and feed product applications so as to develop a better

understanding of the associated physiological, biological and chemical mechanisms from the use of seaweed.

• Support the communication and understanding of seaweed research for animal feeds to the livestock industry in Australia.

Aquaculture RIRDC should work with other research organisations such as Fisheries Research and Development Corporation, National Aquaculture Council and the Seafood Co-Operative Research Centre to prioritise investment for the following research. • Research into the propagation and application of seaweeds in both land-based IMTA,

aquaponic and Integrated Agri-Aquaculture Systems (IAAS). • Product development research which utilises the seaweed resource from such systems for

high value market products and/or import replacement products. • Research into the application of seaweed biostimulants in hydroponic systems for the

propagation of vegetables.

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Bioactive and Functional Products for Health and Medicine RIRDC should work with other research organisations such as Fisheries Research and Development Corporation, National Aquaculture Council, the Seafood Co-Operative Research Centre and National Health and Medical Research Council to prioritise investment for the following research. • Research into the propagation and application of seaweeds and micro-algae in inland saline

areas. This has the potential to support the replacement of imports of seaweeds which are used for the production of bioactive substances.

• Support product development research which utilises these seaweed resources to extract new or novel bio-active substances including:

o Bioactives from macroalgae (eg, fucoxanthin) o Bioactives from micro-algae

Energy and Biofuels RIRDC should build upon its biofuels research and work with other relevant research organisations to prioritise investment for the following research. • Research into the identification of commercially viable strains of macro and micro-algae for

biofuel applications.

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1. Introduction

1.1 Background Throughout the world, the average consumer unknowingly consumes and utilise seaweed-derived products in various forms on an almost daily basis. One major seaweed characteristic contributing to its popularity is that they have the ability to form colloidal systems in water. This means that they can give viscosity, gel strength and stability to liquids. With such properties, seaweeds play an important role in the production of a wide and diverse range of products including:

- Whole or unprocessed foods, and processed foods for human consumption - Industrial texturants including foods, toothpaste and paints - Plant fertilisers in agriculture - Animal feeds in agriculture and fish feeds in aquaculture - Bioactives for health, medicine and cosmetics - Energy and biofuels

The outlook for the seaweed industry is strong and positive. It is enjoying rapid growth in areas such as health, medicine and aquaculture. Of importance the ‘more mature’ whole or unprocessed, and processed seaweed food products are being increasingly re-evaluated due to the increased consumer focus upon health and nutrition. Seaweed food products enjoy a reputation for being healthy meals and ingredients throughout Asia, and western markets are now increasingly appreciating the nutritional qualities in seaweeds. While previously these products may have been regarded as novel and new, consumer perceptions are changing with seaweed products such as seaweed rolls (‘nori-maki’ in Japanese or ‘kimpap’ in Korean), and seaweed salads being enjoyed regularly by many western consumers. 1.2 What’s in a Name – Marine Vegetables? The term seaweed is in many cases an unfortunate term as it often leads to images of washed-up, decaying masses of material, fouling popular beaches or coastal areas. Indeed, the term ‘weed’ in a general sense is often considered to mean unwanted or that of a pest. One of the major focuses for this report is the potential for seaweeds to be used for food applications. For this reason, the preference is for the use of the term ‘marine vegetable’. While later in this report we note that botanically, seaweeds are not vegetables, the term vegetable is preferable as it provides a more accurate representation of the food application. Indeed, there are many publications throughout the literature which adopt the term sea vegetables (eg, Cordero 2006, Madlener 1977). In addition, we also note that this study is focussed upon marine vegetables which have the potential to be sourced from either land based fresh water or marine salt water environments. 1.3 The Consumer Today The world seaweed industry is largely a dual market driven by whole or unprocessed food consumers in Asia, and industrial processed food consumers in western markets. However, overlaid upon these two markets, is the recent emerging consumer issue of health and nutrition as reported in many consumer market studies and industry reports (eg, Horticulture Australia (www.horticulture.com.au), National Health and Medical Research Council (www.nhmrc.gov.au). As further support, the following key consumer issues were highlighted by Australian industry groups during the recent Vegetable Industry Conference conducted by AUSVEG in Sydney.

• Household Factor - smaller, single person households. • Convenience Factor - more work, time poor. • Health and Nutrition Factor - quality of life, live and love longer. • Skills Factor - less cooking skills (and transfer). • More complex wants and desires – flavour and calories versus organic and green.

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Another example is the international pan-European integrated program SEAFOODplus which aims to reduce health problems and to increase well-being among European consumers (www.seafoodplus.org). During 2006, consumer surveys were conducted to more accurately understand the consumer meaning of convenience and health. The survey found that for many households this simply meant nutritious and fast to serve. Reduced time and effort was the goal. However, other consumer groups defined convenience and health as foods of high quality which were natural and healthy. This group demonstrated the consumers’ health consciousness and the goal of quality foods with health benefits. 1.4 Objectives This project is focussed primarily upon identifying areas for RIRDC investment into the food research requirements for seaweeds and seaweed products, especially those which may be used as marine vegetables. However, this report shall also identify other research opportunities or seaweed applications which may provide additional broad benefits for rural Australia. This project filters, collates and consolidates information from the International Seaweed Symposium, Japan and Australian industry research to provide recommendations on: a. The potential market opportunities for 'marine vegetables'. b. The potential, or not, of a role and position of RIRDC in supporting the development of a 'seaweed

products' industry. Specifically, the potential for RIRDC investment to add value to areas such as: - Aquaculture industry in inland areas - Biofuels industry - Bioactives/nutraceutical industry - Greenhouse industry and environmental management - Export market opportunities

c. Research investment opportunities. 1.5 Method Stage 1 – Assessment of Potential Markets for 'Marine Vegetables'

- Assess key consumer issues associated with demand for seaweed and marine vegetable products. Progressive results from complementary research supported by RIRDC at the National Centre of Excellence for Functional Foods (NCEFF) shall also be incorporated as appropriate.

- Review of Australian and international experience to propagate seaweed and marine vegetable 'species' from land and coastal-based systems.

Stage 2 – Assessment of Markets and Industry Resources Meet with industry groups, researchers and management in the following areas:

- Aquaculture industry - Biofuels industry - Bioactives/nutraceutical industry - Greenhouse industry and environmental management - Export markets - Federal and State Government regulatory organisations

Stage 3 – Recommendations for RIRDC Research Investment Opportunities

- Identify and qualify research investment opportunities for marine vegetables and/or other seaweed products.

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2. Seaweeds and Consumers – An Overview

2.1 What are Seaweeds? Seaweeds are macro-algae or multi-celled marine algae which in form appear like terrestrial plants. The root like part is called the holdfast, the stem is the stipe and the leaf of the seaweed is the blade or frond. Seaweeds are similar to flowering plants as they are able to use chlorophyll to conduct the process of photosynthesis and create food for growth. However, seaweeds differ from land plants in that the holdfast is used to primarily anchor or secure the seaweed to the substrate instead of absorbing water and nutrients. Rather, the blade or fronds absorbs nutrients for the seaweed to grow from the saltwater. In addition, seaweeds have a process of sexual reproduction based upon either spores and gametes, or an asexual process based upon fragmentation. Scientifically, seaweeds are classified into groups based upon their chemical compounds, process of reproduction and configuration of cells and structure. However, in practice, many people group seaweeds based upon their colour or dominant pigmentation. The red-purplish colour is due to the pigment of phycoerythrin in seaweeds such as Porphyra, Gracilaria, Gelidiella and Euchema. The predominance of the green colour is due to chlorophyll in seaweeds such as Enteromorpha, Caulerpa and Ulva. Pigmentation from fucoxanthum imparts a brown colour in seaweeds such as Laminaria and Undaria. While most seaweeds are considered in the macroalgae form, seaweeds may also occur as unicellular or micro-algae. Depending on the species, their sizes can range from a few micrometres to a few hundreds of micrometers. Micro-algae often form the basic foodstuff for numerous aquaculture species, especially filtering bivalves. They provide them with vitamins and polyunsaturated fatty acids, necessary for the growth of the bivalves which do not know how to synthesize it themselves. As discussed later, micro-algae are able to grow efficiently in both marine and inland saline areas and synthesize oils, chemicals and other nutrients. 2.2 The Global Seaweed Industry There is a large and diverse array of applications and uses of seaweed products. The industry is estimated to have an annual value of some US$6 billion (McHugh 2003) and the largest share of this is for food products. It is estimated that US$5 billion of this is used in food products for human consumption. The other US$1 billion is largely based upon extracting hydrocolloids from seaweed for use in products such as animal feeds and fertilizers. The industry uses some 10-12 million tonnes of wet seaweed annually and this is harvested either ‘wild’ from marine areas or from cultivated seaweed farm areas. Seaweed farming has grown rapidly over the last 10 years as demand for seaweed products has exceeded supply from natural marine resources. Asia accounts for the vast majority of the seaweed farming with China being estimated as producing over 90% of edible seaweeds. There are three common edible seaweeds farmed and used in Asia. In English, these are commonly referred to under their Japanese names. Kombu (Laminaria japonica) and Wakame (Undaria Pinnatifida) are both derived from two different brown seaweeds and are used in soups, wet dishes and even salads. Nori (Porphyra sp.) is derived from red seaweed species and is commonly used as a ‘wrap-up vegetable’ to wrap rice and vegetable products. Seaweeds are also a source of hydrocolloids which are extracted for their gelling and thickening properties. Both red and brown seaweeds are used to produce three hydrocolloids: agar, alginate and carrageenan. For many western countries, the industrial use of hydrocolloids extracted from red and brown seaweeds matches that of the unprocessed seaweed foods consumed in Asia.

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2.3 The Australian Seaweed Industry Australia is a net importer of fresh or dried and frozen seaweed products. Figure 1 shows that for the most recent three year period 2005-2007, Australian imports have been growing at an average of 27% per annum. During 2006-2007, over A$14 million or 5,300 tonnes of seaweed products were imported from countries including Japan, China, Korea, Ireland and Canada.

Figure 1 Australian Seaweed Imports 2002-2007

0

1,000

2,000

3,000

4,000

5,000

6,000

2002-03 2003-04 2004-05 2005-06 2006-07

Seaw

eed

(tonn

es)

Frozen seaweeds Fresh, dried or chilled seaweeds Total Imports

(Australian Bureau of Statistics) The industry in Australia is relatively small and localised, and very few seaweed or micro-algae are commercially exploited (McHugh and King 2006). The four major industries in Australia are: 1. Alginates – Kelp Industries Pty Ltd Tasmania has been established on King Island for over 30 years and is founded on the fact that Australian kelps such as Durvillea sp. contain up to 60% alginate which are some of the highest contents of alginate in the world. Each year some 2,000-3,000 tonnes of cast beach bull kelp is collected, dried and supplied to Scotland for further mixing with other kelps to produce alginates. As a result, King Island is a key and strategic source of raw material for the alginates industry. 2. Fertilisers and feeds for agriculture – Various industry groups in coastal areas around Australia, collect bull kelp (Durvillea sp.) and process the seaweed into liquid fertilizers for horticulture and animal feed for livestock, such as dairy and beef cattle. The fertilizers and feeds are considered a natural and organic source of nitrogen, phosphorous and potassium (NPK) and other beneficial minerals.

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3. Fucoidan bioactive compounds – Marinova Pty Ltd of Tasmania has established a state-of-the-art extraction and fractionation plant to process the brown seaweed, Undaria pinnatifida. Each year some 200 tonnes of the brown seaweed is harvested from the waters of Tasmania to produce high quality fucoidan-based products. These products are in demand for nutraceutical, pharmaceutical and cosmetic products throughout the world. In the 1990’s, U. pinnatifida was the subject of controversy as it is an introduced seaweed species, and was considered a potential threat to the Tasmanian marine environment. The subsequent commercial exploitation of U. pinnatifida as a commercial resource is an important example of how a potentially threatening seaweed species can be successfully managed under the Tasmanian Governments marine environment management plans. Of note, Marinova’s success with its products has resulted in the need to import additional seaweed raw material from South America for fucoidan processing. 4. Beta-carotene – The micro-algae Dunaliella salina is mass cultured in open-air ponds in inland saline areas such Western Australia. Beta-carotene is produced and is used for colour pigmentation in food and other manufacturing industries, and also in vitamin supplements for the health industry. 2.4 Seaweeds and Australian Rural Research Seaweed has previously been identified under RIRDC’s Asian vegetables research program as a potential and emerging food industry opportunity in Australia (Lee and Momdjian 1997). The research identified that limited information existed on the sustainability of seaweeds as a resource and also confirmed the industry concerns for Australian marine ecosystems and environments. Nevertheless, the potential of seaweed as a resource was recognised. RIRDC has also supported other research relevant to the potential of seaweed as a resource especially in rural areas. As shown in Table 2, research to date has largely focussed upon the nature of seaweed products, and their capability and capacity for propagation in marine or rural based systems such as Integrated Agri-Aquaculture Systems (IAAS).

Table 2 Seaweed Related RIRDC Projects

Project/Year Title Researcher(s)

PRJ-000162/2007 Integrated Polyculture Winberg, P.

SWT-1A/2007 Seaweed Agronomy. Cropping in Inland Saline Groundwater Evaporation Basins

Cordover, R.

UMU-27A/2007 Managing Environmental Impacts in Inland Saline Aquaculture

Lymbery, A., Starcevich, M and Doupe, R.

SQC-1A/2005 Bio-Hydrocarbons from Algae

Qin, J.

MFR-2A/2003 Integrated Agri-Aquaculture Systems A Resource Handbook for Australian Industry Development

Gooley, G., Gavine, F.

MFR-1A/2000 R&D Plan for Integrated Agri-Aquaculture Systems 1999-2004

Gooley, G.

97/149/1997 The Australian Seaweed Industry. A Baseline Review of Research and Development.

Lee, B. and Momdjian, K.

DAV-87A/1996 Seaweed as a Source of Omega-3 Fatty Acids and Beta Carotene

Tran, H.

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3. Market Uses of Seaweed Products 3.1 Marine Vegetables for Human Nutrition and Health For most populations, seafood means protein in the form of fish, prawns, oysters and other shellfish. However, there are many other food resources available from the sea. One such example is edible seaweeds. This major resource of the sea is largely ignored in typical western diets. By comparison, edible seaweeds are an integral part of the diet for people who live by the sea in such areas as Asia, Pacific Islands including Hawaii, South America and Africa. However, with the increasing focus upon consumer health and nutrition, seaweeds are now being re-considered in many Western populations for their nutritional qualities. Seaweeds are nutritionally valuable as fresh or dried, or as an ingredient in processed foods. Edible seaweeds are very good sources of vitamins including A, B1, B2, B6, B12, niacin and C. They are also rich in iodine, potassium, iron, magnesium and calcium. (Mondragon and Mondragon 2003, Norziah and Ching 2000, Wong and Cheung 2000). Some notable examples which demonstrate the nutritional qualities of seaweeds include: Omega 3 Fatty Acids. It is well understood that fish oil contains omega-3 fatty acids (OFA) commonly known as docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). However, it is less well known that the fish obtain their DHA from seaweeds. The algae are eaten by smaller marine life and these in turn are eaten by larger fish. The net result is that the DHA is passed along the food chain to eventually the largest fish in the sea. However, the original source of the DHA is seaweed. The industry has reviewed these findings extensively and references may be found through medical groups such as Physicians for Social Responsibility (www.psr.org) or health industry groups such as Martek Biosciences Corporation (www.martek.com). In addition, in research supported by RIRDC, Tran (1996) confirmed that levels of EPA in Australian seaweeds are among the highest levels in the world. Tran also identified that compared with imported edible seaweeds, Australian seaweeds are free from toxic metals. Spirulina Superfoods. A micro-algae species known as Spirulina (Artrospira platensis) is a cyanobacteria also more commonly known as blue-green micro-algae. Spirulina is considered by many as a ‘superfood’ as it contains unusually high amounts of protein, is rich in OFA acids such as EPA and DHA, and is rich in minerals and vitamins including vitamins B, C, D and E. Of note, Spirulina may be cultivated and harvested in natural inland lake areas. Beta-carotene. Dunaliella (Dunaliella salina) is another micro-algae grown in high salinity rural pond areas throughout the world including Australia, California and Hawaii. It is grown for its beta-carotene nutrient, anti-oxidant and pigmentation value in food and health supplement products.

Plate 1 Pink Dunaliella Salina within sea salt

(Source: Wikipedia)

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Seaweeds have been used as food products for thousands of years. These products are part of the cultural diets of Japan, China, Korea and other coastal populations. Nisizawa (2006) reports that Japan has the highest per-capita consumption of seaweeds in the world and Teas (2006) estimates that this per capita consumption is to the order of 4-7 grams/day. It is difficult to be more accurate as seaweed is used so extensively as flavourings for noodles, soups and meals and may also be consumed as snacks, salads or pickled side-dishes. Edible seaweeds come from three major groupings or Phyla: Red Algae (Rhodophyta), Green Algae (Chlorophyta) and Brown Algae and are based upon their pigmentation and reproductive patterns. Outlined below are examples of these seaweeds and their food usage for nutrition and health.

3.1.1 Red Algae a. Nori Nori is probably one of the most well-known and well-liked edible seaweeds throughout Asia and the western world. The dried sheets are used as a ‘wrap-up vegetable’ to cover rice balls containing vegetables in sushi rice, or the nori may also be used as food toppings or garnishes. In parts of Europe, nori may be more commonly known as ‘purple laver’.

Plate 2 Nori or Purple Laver Sheets

(Source: Wikipedia)

While there are many species of Porphyra, for nori the most commonly used species are Porphyra tenera, Porphyra yezoensis and Porphyra umbilicalis. Fresh Porphyra fronds are harvested from specific sea farm regions, and are subjected to proprietary manufacturing processes involving chopping, boiling and reconstitution into dried sheets. As with fine wine, factors such the year of harvest of the Porphyra, marine region for the ‘vintage harvest year’, manufacturing quality and flavour are key determinants to the final grading and pricing for nori. As an example, the marine regions off Asakusa and Tokyo Bay in Japan are well-regarded for the quality of Porphyra that they are able to produce. The popularity of nori has supported the growth of Porphyra production throughout Japan, China, Korea and many other parts of the world including pond and tank based systems in countries such as Israel and Hawaii. Alternate technology based systems have been researched and developed in Israel and Hawaii in an effort to improve upon the traditional cultivation techniques for nori. Nisizawa (2006) reports that the nori cultivated in the land-based tanks in Hawaii were able to produce product which was comparable in quality and flavour to Japanese nori. However, to date these systems have not become widespread in their application. Nori is not confined to usage with sushi rice only. In countries such as Wales, Porphyra umbilicalisis is mashed into a paste to form red laver bread. This laver bread is then used in cooking with bacon, vegetables and fish or is used as gelatine. The French also have similar cooking applications where it is used to thicken quiche or flan type products.

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Nutrition and Health Qualities of Nori Nori seaweed (Porphyra sp.) has been found to be especially rich in the B complex of vitamins including vitamins B6 and B12 (Nisizawa 1987). Healthy levels of vitamin B12 are associated with the regeneration of red blood cells and a reduction in the potential for anaemia. Vitamin B12 promotes body growth and healthy nervous systems. Of significance, vitamin B12 is not found in terrestrial plants. In western diets vitamin B12 is normally found in foods containing red meat, fish, dairy and egg products. b. Agar Bearing Seaweeds Red seaweeds containing hydrocolloid agar in their cell walls are also known as agarophytes. These include certain species of red seaweeds such as Gelidium and Gracilaria. Hydrocolloid agar is a mixture of polysaccharides that are soluble in hot water but becomes water insoluble at room temperature. c. Carageenan Bearing Seaweeds Carageenan is similar to agar chemically, but it contains a higher ash content and requires higher concentrations to form a gel. The original seaweed used for carageenan was Chondrus crispus, a red seaweed found in the North Atlantic. It traditionally gave rise to the term ‘Irish Moss’ and this term is still widely used today. However, more cost effective seaweeds from Asia (Euchema sp.) and South America (Gigartina sp. and Uridaea sp.) are now used for carageenan processing. These seaweeds are cultivated in large open water areas by low cost labour, but are not commercially viable or environmentally acceptable for most similar waters in western countries. Nutrition and Health Qualities of Agar and Carageenan Both agar and carageenan bearing seaweeds are known for being excellent sources of dietary fibre. The health benefits of diets high in fibre has been well documented (www.nhmrc.gov.au). Dietary fibre promotes clearing of the digestive system, reduced cholesterol absorption and lower blood pressure.

3.1.2 Green Algae a. Sea Lettuce These seaweeds include the many species of Ulva and are found throughout the world including Australia. They are consumed raw or cooked in soups, and are high in protein, soluble dietary fibre and a range of vitamins and minerals especially iron. For this reason Ulva has apparently been used in multi-vitamins and health supplements. The similar in form Monostroma is commonly known as ‘slender sea lettuce’, and may also be commonly used in place of Ulva.

Plate 3 Sea Lettuce (Ulva sp)

(Courtesy: P Winberg)

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b. Aonori or Green Laver Another form of nori is known as aonori in Japanese, and is produced from a mixture of green seaweeds such as Ulva sp, and Enteromorpha sp and Monostroma sp. Aonori is similar in taste and use as nori but is less costly to manufacture. It is commonly used in soups, salads and as a sprinkle condiment. c. Sea Grapes These seaweeds include the species of Calerpa racemosa and Calerpa lentillifera and are found especially throughout the Pacific Ocean areas including Australia. They are consumed raw in salads or cooked in soups.

3.1.3 Brown Algae a. Kombu Kombu usually refers to large brown seaweeds or kelps such as species of Laminaria. Common species include Laminaria japonica, Laminaria angustata, Laminaria saccharina. Most commercial Kombu or kelp products are sold dried as pieces or powder, and are re-hydrated in water before use. They are used commonly for salads and soups, and are used as a condiment. Kombu is a rich source of glutamic acid, an amino acid responsible for ‘umami’ (as it is called in Japan), or a fifth taste or flavour beyond the basic tastes of sweet, sour, salty and bitter.

Plate 4

Kombu and the ‘World of Umami’ Taste

b. Wakame Wakame or Undaria pinnatifida is a kelp used widely in Japan, China and Korea for soups, main dishes and salads. Wakame has a subtle sweet flavour and a slippery texture. It is notable for its use in soups such as miso soup in Japan, and in salads especially with tofu. An example of this salad is Chuka Wakame which consists of shredded wakame with a sesame seed and chile dressing. This product is imported into many western markets including Australia from countries such as Japan and Taiwan. As with Kombu, Wakame is rich in polysaccharides and a good source of soluble dietary fibre. Undaria is known also to be rich in compounds such as fucoxanthums and fucoidans, and these are used as supplements for anti-cancer and weight loss.

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Plate 5

Chuka Wakame Salad

c. Hijiki Hijiki (Hizikia fusiformis) is used extensively in Japan, China and Korea for main meals and soups. Hijiki is green to brown in colour when found in the wild. After collection, it is boiled and dried to be sold in the form of dried hijiki. Dried, processed hijiki turns black. To prepare dried hijiki for cooking, it is first soaked in water then cooked with ingredients like soy sauce and sugar to make a dish. Hijiki is black when found packaged in stores. It is a slightly bitter tasting seaweed that comes in short strips about the size of a match. It is similar in texture and appearance to black spaghetti. However, while Hiziki is well accepted in Asia, it is less so in western diets due to the fact that Hijiki is known to contain potentially toxic amounts of arsenic. While it is claimed that arsenic is removed during the commercial processing of Hijiki, many western nutritionists still consider it as a potential health risk.

Plate 6 Retail Packs of Hijiki, Kombu, Nori and Wakame

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d. Bull Kelp Bull kelp (Durvillea sp) is one of the largest macroalgae and is found mainly in the Southern Hemisphere in areas such as Chile, New Zealand and Australia. These kelps are rich in alginates and are used in salads and also as preserved, salted ‘vegetables’.

In Australia, storm cast bull kelp is harvested from beaches on King Island and dried before being exported to Scotland for alginate processing. The King Island kelp is known to contain some of the highest levels and quality of alginates found in kelps throughout the world. e. Giant Kelp Giant Kelp (Macrocystis sp) is found throughout the world and is well-known for forming picturesque under-sea kelp forests. Some Giant Kelps have been found to grow to over 45 metres in length. Kelps are especially used as condiments for soups, salads and other foods. Kelp ash is generally a rich source of iodine and soda carbonate, and is commercially used as fertilisers throughout Britain, Europe, North America and South America. Summary Table 1 has been developed as a summary of the many applications of seaweeds for food products. This table is not meant to be comprehensive but rather illustrative of the breadth and versatility of forms that seaweeds may be used in diets.

Table 3 Examples of Seaweed Food Applications

Food Use Seaweed Type Seaweeds Used Salads Green Ulva lactuca, Ulva rerticulata

Monostroma nitidum Enteromorpha intestinalis Calerpa racemosa, Calerpa lamourouroxii Chaetomorpha crassa

Salads Brown Hizikia Undaria Laminaria Hydroclathrus

Salads Red Euchema denticulatum Gracilaria coronopifolia, Gracilaria salicornia Halymenia durvillaei Kappaphycus alvarezii Laurencia papillosa Porphyra crispate, Porphyra suborbiculata, Porphyra marcosii

Main Dishes Brown Sargassum fulvellum, Sargassum corderoi Undaria

Main Dishes Green Caulerpa peltata Soups Green Ulva,

Enteromorpha Soups Brown Undaria

Laminaria Soups Red Porphyra

Chondrus Gracilaria coronopifolia, Gracilaria salicornia Gracilaria arcuata, Gracilaria verrucosa, Gracilaria crassa

Dessert Red Acanthophora Laurencia Gelidiellia acerosa Gracilaria species

Powders for flavouring

All Various

(Source: Cordero 2006, Nisizawa 2006)

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Important Note: Seaweeds contain a variety of minerals which have been absorbed from seawater. Some brown seaweeds such as Laminaria, Undaria and Hizikia may contain amounts of minerals (eg, iodine and arsenic) which may be in excess of recommended dietary guidelines. As a result, some seaweed may require soaking in water for 20 - 60 minutes prior to use or cooking. 3.2 Seaweeds as Functional Foods

3.2.1 Dietary Fibre Dietary fibre cleans the digestive system, protects the surface membrane of the stomach and intestines from potential carcinogens, and absorbs various substances such as cholesterol, all of which is ultimately eliminated. Increasing dietary fibre has been linked to lower rates of cardiovascular disease, diabetes, obesity, cholesterol and certain cancers. (NHMRC 2005). Brown seaweeds such as Kombu and Wakame are rich in soluble dietary fibre. When soaked in water, these seaweeds release a mucous viscous type material which consists of alginate, fucoidan and protein. It is this fibre in its mucous form that coats the digestive tract and protects the walls from inflammation and potential carcinogens. The alginates and fucoidans in brown seaweeds are the corresponding equivalent to pectins in terrestrial plants such as apples. However, apples contain only approximately 12% soluble fibre whereas brown seaweeds such as Wakame and Kombu may contain up to 45% soluble fibre (Nisizawa 2006). Other seaweeds like the red algae (eg, Gelidium sp. and Gracilaria sp.) and green algae (eg, Ulva sp. and Enteromorpha sp.) contain similar water soluble fibres. Smit (2004) notes that the soluble fibres in edible seaweeds, such as Laminaria, Undaria, Porphyra and Ulva, offers consumers a range of health benefits. It is suggested that these benefits are evident in Asia, but are yet to be realised with western diets.

3.2.2 Cholesterol As noted previously, seaweeds are a rich source of OFA’s which assist in the lowering of blood cholesterol levels. Nisizawa (2006) notes that research in Japan has shown that seaweeds such as Wakame (U. pinnatifida), Kombu (Laminaria sp.) and Nori (Porphyra sp.) have lowered HDL (High Density Lipoproteins) and increased LDL (Low Density Lipoproteins) cholesterol levels in the blood for test animals. Nisizawa reports that the benefits of lower cholesterol is due to the seaweed components such as soluble fibres, polysaccharides and fucosterols. In Australia, Tran (1996) was supported by RIRDC to conduct an extensive investigation of Australian seaweeds as a source of OFA. About four hundred seaweed samples of all major divisions (green, brown and red) were collected along the coastlines of Victoria, South Australia and Tasmania. The lipids and OFA in 400 samples from 155 species were extensively analysed to identify the most likely commercial species. Over 30 species with a high level (>40%) of EPA were identified. The level of EPA was found to be among the highest level found among all seaweed worldwide. In addition, compared with imported edible seaweeds, Australian seaweeds were found to be free of any toxic metals such as arsenic, cadmium, or mercury. Tran also conducted a market survey and confirmed that consumers in Australia are prepared to consume OFA products from either fish oil or seaweeds.

3.2.3 Diabetes Diabetes is caused by the metabolism of a body not functioning correctly, resulting in high blood sugar levels due to either low levels of the hormone insulin or from the abnormal resistance to insulin’s effects coupled with inadequate levels of insulin secretion to compensate. Foods high in dietary fibre, whether of marine or of terrestrial origin, are effective for lowering blood glucose levels. (www.diabetesnsw.com.au). Both agar and pectin contribute to lowering blood sugars and controlling insulin levels. Red algae such as ‘funori’ (Gloiopeltis sp.) and Porphyra sp. powder is of particular interest as research in Japan has shown that these seaweeds are able to significantly lower blood glucose levels in research animal trials (Nisizawa 2006).

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3.2.4 Vitamins, Antioxidants and Minerals a. Vitamins and Antioxidants As with land plants, the vitamin content of seaweeds vary with species. However, one unique difference between land plants and marine plants is that marine algae contain relatively high amounts of vitamins B and C. Of all the seaweeds consumed as a marine vegetable, nori or Porphyra would be the most significant for vitamins. Porphyra sp. is especially rich in vitamins A, B1, B2 and B12. Vitamin B12 is not found in land plants or vegetables. Other marine vegetables with significant amounts of these vitamins include Hizikia sp., Gracilari sp. and Enteromorpha sp. Vitamin A offers antioxidant benefits largely due to its associated origin with beta-carotene. Many studies have shown a relationship between beta-carotene and a reduced risk of chronic diseases such as cancer (NHMRC, 2005).Ordinary vegetables such as carrots and spinach, contain large amounts of beta-carotene compared to many other brown macro-algae seaweeds such as Wakame (Undaria) and Kombu (Laminaria). However Dunaliella sp., a green micro-algae produces beta-carotene in extraordinarily large amounts. This micro-algae is commercially cultivated in large scale inland lake areas throughout countries including Australia, USA and Israel. The market for beta-carotene is significant as it is commonly used as an anti-oxidant supplement with vitamins, A, C and E. b. Minerals As seawater is rich in minerals, it is only logical that marine seaweeds may contain significant amounts of these minerals. Marine seaweeds absorb minerals in their ionic form from seawater, but the concentrations shall depend upon a number of factors including concentration in the waters, growth stage of the algae and competition between the ions for uptake by the algae (Nisizawa 2006, Sanderson 1988) Nisizawa (2006) confirms that marine algae contain significant amounts of the following 16 minerals and that these minerals play important functions in human health and nutrition.

- Sodium - Potassium - Chlorine - Sodium - Potassium - Magnesium - Phosphorus - Iron - Manganese - Zinc - Copper - Cobalt - Sulphur - Vanadium - Iodine - Fluorine

Sodium, potassium and calcium are generally the most abundant minerals and are fundamental for health and normal metabolic functions of the body. Of note, marine algae generally contains more calcium, magnesium and zinc than terrestrial vegetables and in the case of calcium and magnesium, they may generally be at levels of more than ten times that found in vegetables. Commentary Notes on Iodine and Arsenic - Iodine Iodine is an essential trace element for the healthy function of the body’s thyroid hormones which controls functions including the growth of tissue for the central nervous system, hair, nails, bones and skin. Iodine is also important for mental health. Teas (2006) highlights the importance of iodine to general health, and the fact that iodine deficiency is uncommon in Japan and Korea due to the role of seaweeds in their diets. In Australia, the NHMRC (2005) reports that the intake of iodine has fallen since the 1960’s due to the reduced use of iodised salt and changes in industry practices which has eliminated iodine in milk products. NHMRC also notes that the major dietary source of iodine is marine products such as algae, and that iodine is low or scarce in terrestrial vegetables.

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The recommended dietary intake of iodine for adults is 150micrograms/day (NHMRC 2005) and it is important for both nutritional and physiological health. However, researchers also note that while a deficiency of iodine can lead to problems for the function of the thyroid gland, it should also be noted that an excess of iodine can be toxic and lead to ill health (Thomson 2004). Lastly, Teas reports that other studies strongly suggest that iodine may significantly lower risks associated with various cancers and viral infections including the HIV virus. - Arsenic As with iodine, arsenic in excessive amounts can be toxic to human health. Arsenic can be found in relatively large amounts in certain species of seaweed. The seaweed which is often cited as of the most concern is Hizikia sp. which is consumed extensively throughout Japan. National health authorities have clear guidelines for acceptable concentrations (eg, less than 3ppm in Japan) of arsenic in edible seaweed products. In a study of Tasmanian seaweeds, Sanderson (1988) indicates that inorganic arsenic is the most toxic, and its ultimate source in seawater is from arsenic rich rocks or industrial wastes. While Sanderson notes that overall there has been little research on the arsenic content of Australian seaweeds, it was to be expected that Tasmanian seaweeds would be relatively arsenic free. Nevertheless, further research is needed to confirm the toxicity of arsenic in Australian edible seaweeds. 3.3 Marine Hydrocolloids for Industrial Foods As described above, seaweeds have traditionally been used as sea vegetables especially in Asia. However for many western countries, the industrial use of hydrocolloids extracted from red and brown seaweeds matches that of the raw seaweed ‘marine vegetable’ foods consumed in Asia. Hydrocolloids are tiny polymer particles or molecules dispersed in a water or aqueous mixture. These hydrocolloids from seaweeds or marine hydrocolloids, are applied in the food industry for their functional characteristics such as gelling, thickening, stabilising, emulsifying and anti-caking. These characteristics depend on the complex nature of the polysaccharides in the seaweeds and give rise to the three major hydrocolloid products of agar, alginate and carageenan. The following provides an overview of these products and more detailed information about hydrocolloids from seaweeds can be found at various industry websites (eg, www.cybercolloids.net.) i) Agar Agar is able to bind relatively large amounts of water to form a gel substance often called ‘elastic jelly’. It is manufactured from certain species of red seaweeds such as Gelidium and Gracilaria. Agar is a mixture of polysaccharides that are soluble in hot water but becomes water insoluble at room temperature. As agar forms gels are very low concentrations and is able to bind with large quantities of water, it can be used as a stabiliser in a range of foods including pastries, jellies, ice cream and processed meats. It is also recognised as a good source of nutritional fibre (Nisizawa 2006). Agar is also well-recognised for its use as a bacteriological medium as many micro-organisms are unable to decompose agar. As a result of this property, agar is used extensively as a culture medium for medical and plant tissue applications As a food product, agar is still largely a traditional food item in Asian markets but it is targeted at higher value food market uses, as opposed to the industrial food ingredients market. Major seaweeds used for agar include Gelidium sp. and Gracilaria sp. Agar is imported into Australia from suppliers such as Japan, China and Thailand, and as Gracilaria sp. can be commonly found in Australian waters, researchers in Australia have investigated the opportunity to propagate Gracilaria sp. for the agar market. However, a review of the import statistics over the last five years indicates that while the Australian market for imported agar has grown to a modest 70 tonnes per annum, the average price for agar has decreased over the last 5 years from A$27/kg to A$15/kg in 2007 (ABS Statistics). Discussions with Australian researchers (Cordover (pers. comm. 2007), Kumar (pers. comm. 2007)) confirmed that the agar market is very competitive and there is a need to develop higher value applications for agar from species of Gracilaria seaweed.

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ii) Alginates Alginates have similar applications as agar but tend to be more widely used due to their broader gelling properties. In food, they may be found in products ranging from sauces and jellies to meats, pastry and ice creams. Alginates are used extensively in the textile and paper industries and also the biotechnology industry for applications including the slow-release of medicines and drugs. Major seaweeds used for alginates include Ascophyllum nodosum, Laminaria sp., Macrocystis sp., Sargassum sp., Durvillea sp. and Ecklonia sp. These two latter seaweeds are commonly found in waters in southern Australia. During the 1960’s, Durvillea sp. and Ecklonia sp. were harvested and used in Tasmania for alginate processing. However, due to world competition average market prices for alginates fell as low as A$6.50/kg (McHugh 2003), and these operations are no longer commercially viable. iii) Carageenan Carageenan is similar to agar chemically, but it contains higher ash content and requires higher concentrations to form a gel. However, due to its ability to stabilise water/fat emulsions during preparation, cooking and storage, it is able to increase the quality and yield of food products, and common household items such as toothpaste, hand creams, paints, inks and cosmetics. The nature of carageenan makes it quite suitable for a range of food applications. It is estimated that 70% of the applications are for meat products and the other 30% are for dairy products. The markets are relatively mature and saturated in western markets, but are expected to grow in developing markets due to their increasing ability to afford meat and dairy products in their diets. It has been anecdotally indicated that the pet food and toothpaste markets for carageenan are also growth areas in the Asian markets, again due to the growing affluence of the economies. 3.4 Seaweed Biostimulant Products in Agriculture a. Biostimulants and Plant growth Seaweeds have been used routinely in horticultural practices for many centuries. The seaweed may be added directly to soils and allowed to compost, or the seaweed may be dried and ground into a meal before application to soils. Both the seaweed compost and meal act as a slow release fertiliser, and condition and aerate the soil. Generally, unprocessed seaweeds such as brown seaweeds have similar nitrogen, phosphorous and potassium, salt and micronutrient levels as animal manures. The commercial manufacture of seaweed as powder and liquid concentrates is well established around the world. Common seaweeds used in these products include Ascophyllum nodosum, Fucus sp., Sargassum sp. and Laminaria sp. in the northern hemisphere. In southern hemisphere areas such as Australia, seaweed species including Ecklonia and Durvillea are commonly used and marketed. Australia imports significant quantities of seaweeds from Canada and it would appear that these are used as biostimulants for plant growth. These products are often attractive as they are a natural organic product and may often be more cost effective than synthetic fertilisers. b. Biostimulants for Animal Livestock Feed As with horticulture, seaweeds have also been used widely in animal production industries especially in Europe and North America. Common seaweeds used in these products include Ascophyllum nodosum, Schizochytriu sp., Laminaria sp. and Durvillea sp. However, commercial application of these products is less widespread than those in the horticultural industries. Discussions with industry groups in Australia have been conducted with growers and animal feed suppliers and it would appear that there are several factors contributing to their limited use: - Functionality of Seaweed. Overseas research indicates that the fibre gelling characteristics of some seaweeds may affect their use as animal fodder because they increase food retention and slow digestion and absorption. Animals have also showed an alteration to their digestion of proteins. - Formulation of Feed Diets. There has been a significant amount of investment into the development of feed programs to optimise productivity, feed conversion rates and yields. Both growers and feed suppliers noted the accuracy (and functionality) associated with various components in feed formulations. Often a variation of only 1% of the formulation would potentially have significant effects upon animal yields and costs of production.

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- Manufacturing and Availability of Seaweed Material. As with any manufacturing industry, the feed supply industry is based upon volume and throughput. New dietary feed components such as seaweed are not considered to be assured and/or available for supply in Australia. However, overseas research has shown that commercially prepared seaweed products are beneficial when used as supplements in a range of diets for animals including beef, dairy cows, lambs and pigs. (Braden et.al. 2007, Saker et.al. 2003, Turner et.al. 2002, Franklin et.al. 1999). They have all been found to provide benefits ranging from improved growth performance and carcase quality, to resistance to disease and nutrient content in the meat. 3.5 The Value-Adding Role of Seaweed in the Aquaculture Industry In research supported by RIRDC, Geno and Geno (2001) reviewed the principles of polyculture or multiple cropping land management systems. Polyculture in an agricultural context is in its simplest form using multiple crops, and avoiding large scale single cropping or monoculture. It includes crop rotation, multiple cropping and inter-cropping. The research reports on the failure of industrial monoculture systems to provide ecologically sustainable land use practices. It is quite likely that future production systems shall be based upon a reduced land base and fewer external resources. These principles apply equally to other industries including forestry, animal production and aquaculture production systems. The FAO (2006) estimates that the aquaculture industry is the fastest growing food producing sector in the world. It accounts for some 50% of the world’s fish which is used as food. A number of trends are emerging in the industry. One of these trends is the industry’s shifting of focus from high yields per unit area to economic and environmental sustainability, and overall competitiveness. In the aquaculture industry this has given rise to the term Integrated Multi-Trophic Aquaculture (IMTA) which is a polyculture-type practice in which waste materials from one aquatic species are recycled to become inputs for another. For example, fed aquaculture such as fish or shrimp, are cultured with seaweed and shellfish to create a balanced system which is commercially viable, environmentally sustainable and socially acceptable. Multi-Trophic refers to the incorporation of species from different nutritional levels in the same system. This is an important distinction from many aquatic polyculture systems where many different fish species of the same trophic level are cultured together and often caused added chemical and biological loads to the ecosystem and environment. Ideally in the IMTA system, the chemical and biological processes should be balanced. In essence the fish and the seaweeds balance each other in terms of their impact upon the environment. IMTA systems can be land-based tank and pond systems or open-water systems and may comprise several species combinations. However, simpler systems comprise fish, seaweed and shellfish. Such IMTA systems have been researched and developed throughout the world in Japan, China, South Korea, Thailand, Indonesia, Canada, Chile, Israel, South Africa and Scotland. (Neori and Shpigel 2007, Chopin 2006). The seaweed component of IMTA systems effectively act as bio-filters to clean the water by using the excess nutrients such as nitrogen and phosphorous in the water and then grow to create a biomass. Ulva and Gracilaria are seaweed species which have been demonstrated as suitable for use in IMTA systems (Neori 2007, Neori et. al. 2004). In addition, these co-cultured seaweed species should be more than just biofilters; they should be harvestable crops of commercial value. As an example, researchers in Western Australia have demonstrated that in aquaculture systems, species of Ulva were not only an effective bio-filter of waste products, but were also valuable as a feed supplement for abalones (Daume 2006, Boarder 2001). The commercial value question is a critical issue for the further commercial development of IMTA systems. Seaweeds are technically valuable for the bioremediation of waters in IMTA systems. The key question is ‘Are the IMTA seaweeds in themselves of commercial value?’ While this is largely a commercial market issue, the types of seaweed species shall have an important bearing on the commercial value of the seaweed products. For example, there are many species of Ulva and the variations between yield, protein and mineral content can be significant. (Neori and Shpigel 2007).

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Overall, to date it would appear that there has been limited commercial market use of seaweeds derived from IMTA systems. The types of seaweeds suitable for IMTA systems in Australia and their potential commercial uses is the subject of current research in Australia. Can Seaweeds be Cultivated in Tanks or Ponds? Yes. As indicated by the IMTA systems above, seaweed has been cultured in land-based tank or pond systems throughout Asia and other countries such as Israel, Canada and France. (Neori 2007, Braud 1998). Some examples include:

- France developed a system where Chondrus crispus and a micro-algae (Odontella aurita) were cultured together in tanks for use in both the carageenan and the food industry (Braud 2006).

- Acadian Seaplants Limited in Canada developed a tank farm system where Hana-nori or Irish Moss (Chondrus crispus) are cultured especially for use as a salad vegetable for export markets.

- Sinaloa Seafields International in Mexico grow ao-nori (Ulva) in ponds for use as a supplement for shrimp and animal feeds.

- In South Africa, Ulva sp. and Gracilaria sp. are cultured in tanks for use as abalone feed. However, an important issue is that marine seawater has been used in these systems. There appears to be limited successful application of seaweeds in freshwater tank or pond based systems. Discussions with international and local Australian researchers indicate that seaweeds are most suited to the salinity and ionic composition of the seawater from their endemic environment. Some species of seaweeds are tolerant to variations in the salinity the seawater, but studies have shown that these variations may adversely affect the rate of growth of the seaweed and the biomass and nutrient yield. As an example, RIRDC supported Cordover (2007) to develop baseline research information on the agronomy of Gracilaria seaweed species in inland saline pond areas throughout Victoria. Species of Gracilaria have the potential to transform degraded and water-logged saline areas into a productive and profitable source of seaweed raw material for agar gel for the food and cosmetics industry. However, during the research the following limitations were identified for the profitable and productive use of the saline groundwater for the cultivation of Gracilaria sp.

- The limited range of the chemical composition of the saline groundwater. - The limited availability of critical nutrients or the over abundance of certain minerals. - The low growth rates of the Gracilaria sp. in the saline groundwater.

In studies of inland saline land aquaculture systems, Partridge et.al (2007) and Lymberry et. al. (2007) also reported that the efficacy of seaweeds in inland saline waters was limited by both the variation of salinity and ionic composition of the saline pond water, and the fouling caused by settling solids. Nevertheless, Land and Pang (2006) foresee a bright future for seaweed aquaculture using seawater in tanks in greenhouses. They indicate that the land-based seaweed aquaculture systems shall gain increasing attention due to the potential to cultivate the seaweeds as ‘sea vegetables in greenhouses’. This shall be supported by the plentiful supply of seawater when compared against the increasing scarcity of fresh water as used by terrestrial vegetables. Integrated Agri-Aquaculture Systems (IAAS) Resource utilisation and environmental issues have become important especially as aquaculture may co-exist not only in coastal areas but also in rural farming areas. Integrated Agri-Aquaculture Systems (IAAS) is where aquaculture is integrated and used in traditional farming business’s. In Australia, Gooley and Gavine (2003) conducted research for RIRDC and note that these systems offer significant advantages over conventional farming systems including:

- Increased farming productivity and profitability. - Farm diversification into higher value crops including aquatic species. - Re-use of farm resources such as waste waters. - Reduce environmental issues.

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While seaweeds are cited as of potential use in IAAS systems, it would appear that they have had limited commercial application. As with the IMTA systems, further research into the application seaweeds in IAAS systems and their commercial use is required. Aquaponics Aquaponics is the term given for where aquaculture systems may be integrated with hydroponic plant systems. Aquatic animal effluent (eg, fish waste) accumulates in water as a by-product of keeping them in a closed system such as a recirculating aquaculture system The effluent rich water becomes high in plant nutrients but this is correspondingly toxic to the aquatic animal. Plants are grown in a way (such as a hydroponic system) that enables them to utilize the nutrient rich water. The plants uptake the nutrients, reducing or eliminating the waters toxicity for the aquatic animal. The water, now clean, is returned to the aquatic animal environment and the cycle continues. Aquaponic systems do not discharge or exchange water. The systems rely on the ‘symbiotic’ relationship between the aquatic animals and the plants to maintain the recirculating aquatic environment. Many examples of commercial aquaponic systems exist in Australia and include fish species such as murray cod and barramundi. Barramundi Blue Aquaculture is an example where tank waste waters are used to grow hydroponic plants such as lettuce and flowers (www.aaq.com.au/geoff_orpin.htm). Similarly, Tailor Made Fish Farms (www.tailormadefishfarms.com.au) raise barramundi, and tank water is used to grow Asian vegetables such as buk choy, lettuce, silverbeet and herbs in hydroponic channels. It is reported that such barramundi (and other prawn farms) are reviewing the opportunity to incorporate green seaweed into the aquaponic systems (Kain 2003). The integration of seaweed into these systems is a logical consideration but shall be subject to technical research and/or market demand for the seaweed products. 3.6 Seaweeds, Biofuels and Energy The recent Biofuels report for RIRDC by CSIRO (2007) describes the growing worldwide trend to search for alternative energy sources due to world oil prices and concerns about greenhouse gas emissions. Biofuels offer the potential to support future energy needs in Australia and a range of feedstocks for biofuel production are potentially available. The report notes that future second generation feedstocks such as terrestrial plants and algae could greatly expand supply for biofuels. Algae have the potential to produce oils for biodiesel but the production is ultimately limited by the oil in the algae feedstock. Research into the extraction of oils from seaweeds for biofuel feedstocks has followed two paths: - Macroalgae Macroalgae or seaweeds in the form of floating seaweed farms in oceans is the subject of current research in countries such as Korea and Japan. Research is under progress in Japan to develop vast floating seaweed platforms that follow the ocean currents. The research team plans to develop 100 vast nets full of quick-growing seaweed, each measuring six miles by six miles, floating off the northeast coast of Japan. The seaweed in each net, growing to a weight of 270,000 tonnes a year, will potentially absorb large amounts of greenhouse gases and convert them to oxygen before being harvested 12 months later as a rich source of biomass energy. Seaweed in this form may offer potential greenhouse benefits if the seaweed can act as a carbon sink. CO2 removal from the atmosphere can support Clean Development Management (CDM) strategies under the Kyoto Protocol. The Korea Government through researchers at Pusan University are sponsoring a seaweed CDM project to use seaweed as a carbon sink. The Greenhouse Gas reduction project is for the period 2006-2011 and involves international collaboration including Australian researchers at Monash University. Similar applied research is also being conducted in China and Japan. It is understood that the concept of floating seaweed platforms is the subject of a small scale commercial trial in Tasmania. However, in general the lipid content in macroalgae generally tends to be to the order of no more than 4% of dry weight (Sanchez-Machado et.al. 2004). As a result many researchers express concerns about the viability for biofuels given such relatively low concentrations of oil in macroalgae.

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- Micro-algae Micro-algae for oils for biofuels have been the subject of research for a long period of time. The US Department of Energy’s Office of Fuels Development supported a Biodiesel from Algae project for some 18 years between 1978 and 1996. This project confirmed that many species of micro-algae contain high levels of oils often in the range of 25-60% of dry weight. They found that micro-algae are remarkably efficient converters of solar energy and are capable of producing 30 times the amount of oil per unit area of land when compared to terrestrial oil crops. These results are also confirmed by research supported by RIRDC at Adelaide University (Qin 2005). This research showed that Botryococcus braunii, a green micro-algae found in lakes and reservoirs in Australia, may contain oils up to 75% of dry weight. More recently, it has been reported that Seambiotic Ltd, an Israeli company has developed a new technology that involves the absorption of CO2 from fossil fuel (eg, coal) power plants. In experimental ponds, the CO2 was passed through a filtration system to ‘power-feed’ micro-algae in seawater for their oil bearing potential (see www.haaaretz.com/hasen/spages/837175.html) 3.7 Bioactive and Functional Molecules Wondu Holdings (2000) reports that the global market for herbal supplements, minerals and vitamins is valued at US$45 billion and is expected to continue to grow at double digit rates. In Australia, the demand for new pharmaceutical, nutraceutical and industrial products is being driven by consumers increasing demand for improved health and quality of life. It is within this context that the bioactive substances in raw materials from natural products such as seaweed are increasingly be reviewed. Smit (2004) notes that the substances which currently receive the most attention from pharmaceutical companies and researchers include sulphated polysaccharides as antiviral substances, halogenated furarones from Delisea pulchra (a red algae) as bacterial antifouling compounds, and kahalalide F from Bryopsis (a filamentous green seaweed) as a possible bio-film treatment for cancer, tumours and HIV. In Australia, industry has focussed upon the polysaccharide components called fucoidans found in Undaria pinnatifida, the non-native brown macroalgae introduced into the waters of Tasmania. Fucoidans have significant presence in the nutraceutical and cosmeceutical market areas because of their bioactivity. Fucoidans are generally highly sulphated, and of high molecular weight, but are ‘water soluble’. They act as anti-inflammatories, anti-pathogenics and immune modulators. They may also act as enzyme inhibitors and growth factor promoters. Fucoidans, when isolated, have very little odour or taste, yet have concentrated the activity associated with ‘whole seaweed’ products.

Plate 7 Fucoidan Health Supplements

The fucoidan market is increasing, with health supplement and cosmetic manufacturers increasingly realizing the value of this plant based ingredient. Global production of fucoidan is estimated to be to the order of 250 tonnes per annum, with a value of some US$125 million. The fucoidan market is supplied by low cost suppliers from China, mid-range suppliers from Korea, a small number of other

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world manufacturers. The quality of the fucoidan products is generally lower from China, but they produce a low cost product that is sold all over the world. Their manufacturing methodology tends to rely on solvent precipitation and heated acidic extractions. Korean manufacturers are more sophisticated, and have substantial manufacturing facilities. They sell for export to the US market. Japan has higher quality production, with good quality control and manufacturing ability. However, they mainly supply only the internal Japanese market. Australia is a higher end manufacturer and exporter of fucoidan products. Australia utilizes the local Tasmanian seaweed resources of U. pinnatifida, plus high quality imported materials to produce fucoidans. Australia has very little seaweed harvesting, other than the beach cast kelp (King island) and the Tasmanian U. pinnatifida resources. Hence, importation of Undaria sp. is necessary. The value of fucoidan as an ingredient is based on the country of origin, quality control and the manufacturing process, and the amount of evidence available (such as clinical studies). Micro-algae are also the subject of substantial research and development for bioactive substances (Smit (2004)). Paul et.al.(2006) refers to the increasing worldwide occurrence of harmful algal blooms and during these blooms, cyanobacteria may yield concentrations of bioactive substances. For example, it was reported by Paul et.al, that Australian researchers are researching benthic cyanobacteria such as Lyngbya as a source of nitrogenous secondary metabolites which may be associated with anti-fouling and/or biofilms.

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4. Discussion of Results 4.1 Market Applications and Opportunities

a. Marine Vegetables for Human Nutrition and Health There are many food preparations which are based upon seaweeds being used as ‘marine vegetables’. The famous ‘Sea Vegetable Book’ by Madlener (1977), identified the use of more than 25 different species of seaweeds in over 130 different recipes ranging from soups and main meals to salads, desserts and seasonings. As outlined in Chapter 1, consumers today are driving the trend for foods to provide convenience, health and nutrition, quality and naturalness. As a result, the food industry has responded with value-added products based upon convenience, health and functional nutrition benefits. While consumer markets for many of these products may be niche, such products are gaining increasing market acceptance in Australia. This observation is supported by import trade data which shows that Australian seaweed product imports has been growing at almost 30% per annum for the last 3 years. Applications for the use of seaweed products as marine vegetables may be considered in two groups: Group 1 – Current Generation Food Products Group 1 products are existing categories of food products into which seaweeds may be incorporated with a relatively small amount of product development work. Expressed another way, seaweeds may be used as marine vegetable extensions of many current food products. The role of marketing shall be critical to the success of these new products as western culture and attitudes of consumers will be key commercial issues. Examples of these products include:

- Wrap-Up Vegetables Marine vegetables have the potential to build upon the ‘signature’ nori (rice wrapped in seaweed) roll product. Many food products are commonly marketed as ‘wraps’ ranging from fast-food products to Middle Eastern and Mexican tortilla-type products.

Plate 8 Marine ‘Wrap-Up’ Vegetables

- Salads Marine vegetable salads are well-established in many overseas markets as shown by the salad product (Chondrus crispus) (Plate 9) produced by Acadian Seaplants Limited of Novia Scotia. In Australia, the minimally processed fresh cut and ready prepared salad market is estimated at A$350-400 million. It is a strong market experiencing double digit annual growth (industry pers. comm. 2007). Marine vegetable salad products have the opportunity to be included as a product range extension for Australian salads. As shown previously at Plate 5, the imported frozen ‘Chuka Wakame’ product is marketed and sold in Australia and has developed an awareness of the salad potential for seaweeds as a marine vegetable.

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Plate 9

Seaweed Salad

- Health and Natural Foods Marine vegetables lend themselves to being presented as health food products. They may be developed as fresh, frozen, dried or processed. Many of these products are available at health food outlets today, and as with the above products, these existing products are ‘signature or platform’ products which can be further expanded upon. An example is agar gels which are available throughout Asia, but are not commonly consumed in Australia. These products lend themselves to being formulated into Australian natural food formats (and flavours) to capitalise upon the nutritional fibre benefits intrinsic to agar gels.

Group 2 – Next Generation Food Products Group 2 products are existing categories of food products into which seaweeds would require further research and development for new product development. Examples include:

- Soups Dried marine vegetable products are well-established as ingredients for soups in Asia. Dried Japanese miso soup and cup noodle products are examples of these products. However, research shall be required to incorporate these dried marine vegetables into western style soup and meal products.

- Industrial Food Ingredients and Flavours Marine vegetables may be processed and incorporated as ingredients with other foods. Processed marine vegetable products may be suitable for further processing with bakery foods such as biscuits, sauces and dressings and, spice, flavour and powder condiments.

- Functional Natural Foods These products would be new and novel for the Australian market but would be logical extensions or enhancements of the health and natural foods in Group 1 Current Generation Food Products. Seaweeds and micro-algae possess many functional benefits associated with:

- Dietary fibre - Cholesterol - Diabetes - Vitamins, antioxidants and minerals

The National Centre of Excellence for Functional Foods (NCEFF) is conducting a concurrent study into functional food publications using seaweed products. The results of this work shall provide greater detail of consumer and product developments of such functional foods throughout western markets. Subject to the NCEFF study, many researchers consider that there are significant opportunities for the use of seaweeds as functional ingredients or functional food products in western diets (Smit 2006, Nisizawa 2006, Kain 2003).

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In general, there are current and potential market applications for marine vegetables as both marine vegetable and functional natural foods. However, a major limiting factor for the further development of these products in Australia is the availability of seaweed supply from local Australian resources. Existing markets for these products in Australia are largely supported by imported seaweed products. Research to support the development of Australian seaweed resources for Australian food products shall be strategically important and is discussed further below.

b. Seaweeds for Fertiliser and Feed Products in Agriculture For plant growth, the beneficial effects and physiological responses associated with the use of seaweed include:

- Vigorous root systems and improved growth. - Nutrient mobilisation and absorption. - Fruit and crop yield. - Increased fertiliser efficiency. - Increased chlorophyll content. - Increased resistance to stress. - Resistance to frost and insect damage. - Retardation of senescence.

However, Stirk and Van Staden (2006) note that the physiological mechanisms associated with these beneficial effects are not well understood. A better understanding of these mechanisms would enable plant products to be better managed to optimise yields. Moreover, it is also noted that these mechanisms when used in hydroponic and aquaponic systems have not been the subject of significant research. For animal livestock feed, overseas research has shown that commercially prepared seaweed products are beneficial when used as supplements in a range of diets for animals including beef, dairy cows, lambs and pigs. They have all been found to provide benefits ranging from improved growth performance and carcase quality to resistance to disease and nutrient content in the meat. However, their use in the Australian industry is less than widespread due to issues associated with functionality, formulation programs and availability of seaweed product. For both fertiliser and feed products applications, further research is required to develop a better understanding of the associated physiological, biological and chemical mechanisms from the use of seaweed, especially those that may be sourced from Australia.

c. Seaweeds for Industrial Hydrocolloid Foods and Products The seaweed hydrocolloid market is a competitive industry dominated by large multi-national corporations and large emerging low cost manufacturers in Asia. Discussions with Australian researchers confirmed that the agar market was very competitive and there was a need to develop higher value commercial agar applications. Such commercial applications would support research efforts to propagate species of agar-bearing Gracilaria seaweeds in inland saline areas. As discussed, hydrocolloids are also used in special industry applications for thickeners, gels and stabilisers in products such as textiles, paints and printing. With the exception of niche market opportunities, it is unlikely that Australia would have a competitive advantage for the supply or manufacture of hydrocolloids.

d. Seaweeds and Micro-algae for Biofuels and Energy The key limiting factors for the commercial application of algae for biofuels appears to be the identification of commercially viable strains of macro and micro-algae, and the associated yields and costs of production. Research expertise for biofuels and algae exist in Australia. Groups such as SARDI in South Australia and other researchers in Western Australia are involved with programs for the breeding and application of micro-algae in both inland saline areas and in floating tank systems.

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In addition, other Australian researchers plan to use micro-algae as a low cost source of biomass for pyrolysis processing. Such processing results in the extraction of bio-oils and gases, and bio-char for carbon sequestration in soils. During the International Seaweed Symposium, papers were presented of research into other forms of energy. The research showed that: - The fermentation of one tonne of seaweed can produce 20 kilolitres of methane in bio-reactors. - Seaweeds can be used as combustion materials to generate steam in solar oxygen fuel turbines. - Approximately one million tonnes of wet seaweed can run an economically feasible bio-ethanol

plant to generate ‘clean’ power and also reduce CO2 emissions. Large floating ‘sea farms’ in Asia are being considered as a source of biomass for such applications. It is also reported that small scale trials of floating platforms of macroalgae are under review and development in Tasmania.

e. Bioactive and Functional Products for Health and Medicine There is considerable opportunity to build on the current success in Tasmania to extract high quality fucoidan from brown seaweeds and further expand exports. The industry is most interested in the prospect of sourcing Australian grown seaweeds from land-based areas, and will also consider the extraction of other bio-active components, such as fucoxanthin from such materials. It is also noted that recent international research is also focussed upon micro-algae especially for health and medical applications (Smit 2004). These industry applications are capital and technology intensive. The intellectual property associated with these products shall be a key competitive advantage. 4.2 Strategic Sources of Seaweed in Australia The availability of a seaweed raw material biomass is critical to the future growth of the industry. Compared to many Asian countries, seaweeds in the marine waters of Australia and many other western countries are (understandably) subject to legislation and industry plans for the management of marine resources and environments. Many Australian marine environments are recognised for their natural ecological value. In this respect many may think of the Great Barrier Reef in the warm tropical waters of Queensland, however other coldwater temperate waters are just as important. These temperate waters include Tasmania, Victoria, South Australia and southern Western Australia, and contain some of the highest numbers of species of seaweeds in the world. With the growth of commercial, environmental and social pressures, marine management plans have been developed to ensure the future commercial viability and sustainability of the marine resources. When it is also considered that management plans limit the available supply of seaweed to Australian seaweed industry groups, Australian open-water marine coastal environments in Australia cannot be considered a future strategic seaweed resource. By comparison, Australian and international industry and research groups indicate that the growth and management of aquaculture systems are a potential source of seaweed raw material. Such a raw material resource is emerging from IMTA and aquaponic tank or pond systems.

a. The Aquaculture Industry In the report on the State of World Aquaculture 2006, the FAO confirm that aquaculture is developing and expanding throughout almost all regions of the world. The FAO expects that as the global population continues to expand, supplies from capture fisheries will reach their maximum potential and will not be able to meet this growing demand. Aquaculture has the potential to significantly contribute to this increasing demand, and the FAO predicts that the global aquaculture industry shall need to increase production by some 80% by 2050 in order to maintain current levels of per capita consumption demand for aquatic food products. In particular, the FAO notes the trend for aquaculture systems to become more intensive. This trend is largely being driven by the unavailability of sites for aquaculture and competition for land and water. This has resulted in a higher degree of integration of agriculture and aquaculture. Polyculture and IMTA marine systems offer improved productivity, improved resource efficiency and more

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sustainable environmental impacts. In this context, seaweed aquaculture is emerging as an important part of marine land-based tank and pond systems. Such systems shall potentially provide a valuable and significant source of seaweed biomass for food and non-food products. As an example, initial estimates associated with potential IMTA systems for Australia indicate that 2,000 tonnes of wet weight seaweed (or approximately 200 tonnes dry weight) would be expected for a fish production of approximately 1000 tonnes in a 20 hectare tank system. This is based on a system designed for efficiency by Neori et. al. (2003), however other systems have reported varying quantities of seaweed and fish. As discussed in Section 3.5 above, there is international experience for the cultivation of the following seaweeds in a range of markets.

- In France, Chondrus crispus and a micro-algae (Odontella aurita) are cultured together for use in both the carageenan and the food industry.

- In Canada Hana-nori or Irish Moss (Chondrus crispus) are cultured especially for use as a salad vegetable for export markets such as Japan.

- In Mexico, Aonori (Ulva sp.) is grown in ponds for use as a supplement for shrimp and animal feeds.

- In South Africa, Ulva sp. and Gracilaria sp. are cultured in tanks for use as abalone feed. Future research may support the application of seaweed aquaculture in two areas: i) IMTA Greenhouse Systems – Land and Pang (2006) foresee a bright future for seaweed aquaculture using seawater in tanks in greenhouses. Obvious advantages of land-based seaweed systems in greenhouses include: - Controlled environment bringing better control of nutrients. - Better control of the density of the seaweed growth. - Year round control of yield and productivity. - Manipulation of ‘daylength’ and thus plant reproduction and seasonality. ii) Aquaponic Systems - Aquaponic systems using a range of hydroponic plants including vegetables is relatively established. The integration of seaweed or algae into these systems in Queensland has been reported by Kain (2003) as a logical consideration but shall be subject to the market demand for the seaweed products.

b. Integrated Agri-Aquaculture Systems (IAAS) Seaweed aquaculture and IMTA systems may co-exist with agriculture but would be restricted to coastal areas due to the need for available seawater. Such an additional land-use would be consistent with many other commercial applications of Integrated Agri-Aquaculture Systems. Research should be conducted to identify suitable marketable seaweeds for IAAS in coastal areas.

c. Inland Rural Areas Strategic research has been conducted to cultivate seaweed in rural Australia. However to date, there has been limited success for the application of seaweed aquaculture in either inland saline land or freshwater systems. A major factor has been that the chemical composition of seawater is difficult to replicate for the survival and (optimal) growth of seaweeds. However, it is noted that the research to date has focussed upon seaweed species such as Gracilaria for food market and aquaculture feed applications. Industry discussions have identified that other brown seaweeds may be suitable for propagation in inland saline areas and may offer alternative sources of material for the extraction of bioactive substances. Of related interest, recent research in Israel has identified a highly edible plant which is able to exist and flourish in brackish and inter-tidal wetland areas. Shpigel (2006) found that the succulent salt-tolerant (halophyte) Salicornia europea was an effective biofilter, and is reportedly gaining in popularity as a health and gourmet food. The plant can be consumed raw or cooked, and apparently after cooking while it appears seaweed in colour, its flavour and texture is similar to spinach stems or asparagus.

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It is also noted that the Australian aquaculture industry has conducted extensive research into aquaculture in inland saline areas (see www.australian-aquacultureportal.com). Further research of seaweeds in inland saline areas should be conducted in co-ordination with the National Aquaculture Council (NAC). 4.3 Summary In general, there are current and potential market applications for seaweeds as saltwater marine vegetables, functional natural foods and non-food products. There has been limited development and application of seaweeds in freshwater. A major limiting factor for the further development of the saltwater seaweed products in Australia is the availability of seaweed supply from local Australian resources. Existing markets for these products in Australia are largely supported by imported seaweed products. Table 1 provides a summary of the industry groups and the broad market and research drivers for the seaweed products. The major research driver is the ability to develop a source of seaweed supply from land-based propagation systems. Such systems are the subject of international research and it is important for Australia to either apply existing technologies and systems or develop proprietary alternatives. In either case, the Australian applications must be cost competitive if it is to compete with global suppliers and importers. As this study is essentially collating and filtering international and Australian information, it is difficult to conduct any further assessment as to the priority of the issues. The assessment of the priority for these products shall be predicated upon commercial feasibility studies associated with the various applications.

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Table 1 Summary of Market and Research Drivers for Marine Vegetable and Seaweed Applications

MARKETS FOOD AGRICULTURE ENVIRONMENT HEALTH

KEY CRITERIA

Marine Vegetables

Texturants Animal Feed

Fertilisers Energy and Biofuels

Aquaculture Bioactives for Health and Medicine

Stage of Market - Emerging - Growth - Mature

Emerging

Mature Emerging

Growth

Emerging

Growth

Growth

Primary Market Drivers

Consumer nutrition and health

Low cost production

Commercial feasibility

Commercial feasibility

Commercial feasibility

Commercial & environmental sustainability

Health and medicine

Primary Research Drivers

- Availability of seaweed - Product development

Applications research

Applications research

Applications research

Propagation and yields of seaweed and micro-algae

Propagation of seaweed in land based systems

- Propagation of seaweed in land based systems - Product development

Rural benefits - Commercial

Yes No Yes Yes Yes Yes Yes

Rural benefits - Community

Yes No Yes Yes Yes Yes Yes

Rural benefits - Environment

Yes No Yes Yes Yes Yes Yes

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5. Implications The food market in Australia with its focus upon health and nutrition provides opportunities for researchers to consider seaweeds as marine vegetables. While marine vegetables are staple food items in Asian markets, they represent small and niche markets in Australia. Nevertheless, ‘East continues to meet West’, and these markets continue to grow. The Australian seaweed industry is small and localized. The availability of seaweeds is the constraining factor for the growth of the industry. Currently, the Australian market is largely supplied by seaweed food imports with annual import volumes of over 5,000 tonnes in 2006/07 and an approximate value of A$14 million. This implies that there is a significant Australian market opportunity for seaweed products and the potential for import replacement if the Australian industry is commercially competitive. Conversely, this also implies that the opportunity for increased seaweed exports would be limited, especially given the limited availability of seaweed to industry at present. Research to support the development of Australian seaweed resources for Australian food products shall be strategically important. Due to commercial, environmental and social pressures seaweed farming in Australian marine environments is not feasible. Research is needed to develop alternate land-based sources of seaweed. These sources shall provide the opportunity to develop marine vegetable and seaweed products for both the Australian and potentially Asian export markets. Alternate technologies, skills and associated intellectual property should all be evaluated to ensure that the land-based resource shall be commercially viable and competitive with the other major world suppliers. Key research issues for RIRDC to review and assess for its Asian Foods and other research programs should include:

- Proprietary systems to propagate seaweeds in land-based aquaculture, IMTA and aquaponic systems.

- Technologies that enhance the functional value of Australian seaweed for use in foods for nutrition and health.

- Functional value of Australian seaweed for use in other industries including: o Australian biofuel applications o Bioactive and medical applications o Greenhouse industry applications

The above research issues also have the potential to provide significant benefits to the rural industry including:

- Potential for exports of bioactive substances extracted from seaweeds. - Potential for rural areas to diversify their land use and income base. - Potential usage of seaweed and micro-algae in inland areas for biofuel use. - Potential for the utilisation of inland saline areas. - Potential to support Greenhouse management strategies. - Sustainable management of resources.

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6. Recommendations Marine Vegetable Foods for Human Nutrition Compared to other international markets, to date the Australian market has failed to recognise benefits associated with marine vegetable foods. RIRDC should work with co-investors to prioritise investment for the following research. • Strategic research that shall improve the supply of seaweed and micro-algae resources from land-

based systems such as open air IMTA and IMTA greenhouse systems. The land-based systems should be in support of novel or growth market opportunities where Australia has a competitive advantage for supply, quality, technology or intellectual property.

• Product development research is required for food products including: o Seaweed salads o Wrap-up vegetables o Agar gels

Health and Functional Foods Compared to other international markets, to date the Australian market has failed to recognise health and functional food benefits associated with seaweed products. RIRDC should work with co-investors to prioritise investment for the following research. • As per above, support strategic research that shall improve the supply of seaweed and micro-algae

resources from land-based systems. • Subject to a concurrent study by the National Centre of Excellence for Functional Foods, product

development research to develop health food products which utilise the functional qualities of seaweeds and/or micro-algae.

Agriculture The Australian agricultural industry does not fully understand the benefits associated with the use of seaweed fertilisers and animal feeds. RIRDC should work with co-investors to prioritise investment for the following research. • Research into seaweed fertiliser and feed product applications so as to develop a better

understanding of the associated physiological, biological and chemical mechanisms from the use of seaweed.

• Support the communication and understanding of seaweed research for animal feeds to the livestock industry in Australia.

Aquaculture RIRDC should work with other research organisations such as Fisheries Research and Development Corporation, National Aquaculture Council and the Seafood Co-Operative Research Centre to prioritise investment for the following research. • Research into the propagation and application of seaweeds in both land-based IMTA, aquaponic

and IAAS systems. • Product development research which utilises the seaweed resource from such systems for high

value market products and/or import replacement products. • Research into the application of seaweed biostimulants in hydroponic systems for the propagation

of vegetables including Asian vegetables. Bioactive and Functional Products for Health and Medicine RIRDC should work with other research organisations such as Fisheries Research and Development Corporation, National Aquaculture Council, the Seafood Co-Operative Research Centre and National Health and Medical Research Council to prioritise investment for the following research. • Research into the propagation and application of seaweeds and micro-algae in inland saline areas.

This has the potential to support the replacement of imports of seaweeds which are used for the production of bioactive substances.

• Support product development research which utilises these seaweed resources to extract new or novel bio-active substances including:

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o Bioactives from macroalgae (eg, fucoxanthin) o Bioactives from micro-algae

Energy and Biofuels RIRDC should build upon its biofuels research and work with other relevant research organisations to prioritise investment for the following research. • Research into the identification of commercially viable strains of macro and micro-algae for

biofuel applications.

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7. References (including Websites) AUSVEG Limited www.ausveg.com.au Boarder, S. (2001) Demonstration of seaweed nutrient stripping for aquaculture wastewater. Documentation in support of the end of project report for Coasts and Clean Seas Project. Aquaculture Development Unit Challenger TAFE Fremantle Western Australia. Braden, K.W., Blanton, J.R., Montgomery, J.L., van Santen, E., Allen, V.G., Miller, M.F. (2007) Tasco supplementation: Effects on carcass characteristics, sensory attributes and retail display life. J Animal Science, Mar 2007: 85,3. Braud, J. (2006) Continuous Seaweed Tank Culture in France: From Chondrus Crispus to Co-culture of Macroalgae and Diatom Odontella Aurita. In: Seaweed Resources of the World (Critchley, A. T., Ohno, M., Largo, D.B. editors). Japan International Cooperation Agency, Yokosuka. Chopin, T. et.al. (2007) The Renewed Interest in Seaweed Aquaculture as the Inorganic Extractive Component of Integrated MultiTrophic Aquaculture (IMTA) Systems with Fish and Shellfish. Plenary paper presented at the 19th International Seaweed Symposium, Kobe, Japan 26-31 March 2007. Chopin, T. (2006) Integrated multi-trophic aquaculture. What it is and why you should care…and don’t confuse it with polyculture. Northern Aquaculture, V2, No.4 July/August 2006. Cordero, P. (2006) Sea vegetables: Man’s supplemental food. In Seaweed Resources of the World (Critchley, A. T., Ohno, M., Largo, D.B. editors). Japan International Cooperation Agency, Yokosuka. Cordover, R. (2007) Industrial seaweed agronomy in saline drainage water evaporation basins RIRDC Project SWT-1A. CSIRO. (2007) Biofuels in Australia – Issues and Prospects RIRDC Report 07/070 Daume, S. (2006) The Roles of Bacteria and Micro and Macro Algae in Abalone Aquaculture: A Review. J. of Shellfish Research 25, 1, 151-157. Food and Agriculture Organisation (FAO) www.fao.org Food and Agriculture Organisation (FAO). (2006) State of World Aquaculture: 2006 FAO Fisheries Technical Paper 500. Inland Water Resources and Aquaculture Service Fishery Resources Division Fisheries Department, Rome 2006. Franklin, S.T., Martin, K.R., Bare, R.J., Schingoethe, D.J. and Hippen, A.R. (1999) Dietary Marine Algae (Schizichytrium sp.) Increases Concentrations of Conjugated Linoloeic, Docosahexaenoic and Transvaccenic Acids in Milk of Dairy Cows J. of Nutrition, 129, 11. Geno, L and Geno, B. (2001) Polyculture Production Principles, Benefits and Risks for Multiple Cropping Land Management Systems in Australia. RIRDC Publication No. 01/34. Gooley, G. (2000) R&D Plan for Integrated Agri-Aquaculture Systems 1999-2004. RIRDC Publication No.99/153. Gooley, G and Gavine, F. (2003) Integrated Agri-Aquaculture Systems. A Resource Handbook for Australian Industry Development RIRDC Project MFR-2A. Horticulture Australia Limited www.horticulture.com.au International Seaweed Symposium (2007) www.isaseaweed.org/symposia.lasso

32

Kain, J.M. (2003) Seaweed Cultivation in the West is Retarded. In: Out of the Past (Ed. by T.A. Norton), pp. 163-180. The British Phycological Society, Belfast. ISBN: 0 9527115 24. Kraan, S. (2007) Seaweed Aquaculture and the European Perspective. Paper presented at the 19th International Seaweed Symposium, Kobe, Japan 26-31 March 2007. Kumar, V and Fotedar, R. (2007) Technical Feasibility of Cultivating Gracilaria Cliftonii in Different Ionic Profiles of Inland Saline Water. Paper presented at the 19th International Seaweed Symposium, Kobe, Japan 26-31 March 2007. Land, K and Pang, S. (2006) Seaweed aquaculture on land: Current chances and prospects. AQUA 2006 – Meeting Abstract 794. World Aquaculture Society. Lee, B.W and Momdjian, K. (1997) The Australian Seaweed Industry. A baseline review of research and development RIRDC Research Paper 97/49. Lymberry, A., Starcevich, M and Doupe, R. (2007) Managing Environmental Impacts in Inland Saline Aquaculture. RIRDC Report 05/166. McHugh, D and King R. (2006) The Seaweed Resource of Australia. In: Seaweed Resources of the World (Critchley, A. T., Ohno, M., Largo, D.B. editors). Japan International Cooperation Agency, Yokosuka. McHugh, D. (2003) A Guide to the Seaweed Industry. FAO Fisheries Technical Paper 441. Madlener, J.C. (1977) The Vegetables Book. Clarkson Potter Pub. New York. Mondragon, J and Mondragon, J. (2003) Seaweeds of the Pacific Coast. Sea Challengers Publications, Monterey, California. ISBN 0-930118-29-4. National Centre of Excellence for Functional Foods www.nceff.com.au National Health and Medical Research Council (NHMRC) (2005) Nutrient Reference Values for Australia and New Zealand including recommended dietary intakes. Department of Health and Ageing, Australian Government (www.nhmrc.gov.au). National Health and Medical Research Council (2006) Guidelines for Managing Risks in Recreational Water. Department of Health and Ageing, Australian Government (www.nhmrc.gov.au). Neori, A. (2007) Seaweeds, Ecology and Profitable Aquaculture: An Introduction to the Mini-Symposium ‘Integrated Aquaculture: Essential Role of Seaweed Cultivation (Global Expansion of Mariculture) Paper presented at the 19th International Seaweed Symposium, Kobe, Japan 26-31 March 2007. Neori, A and Shpigel, M. (2007) Algae. Key for Sustainable Mariculture. In Seaweed Resources of the World (Critchley, A. T., Ohno, M., Largo, D.B. editors). Japan International Cooperation Agency, Yokosuka. Neori, A., Chopin, T., Troell, M., Buschmann, A., Kraemer, P., Halling,C., Shpigel,M and Yarish,C. (2004) Integrated Aquaculture: Rationale, evolution and state of the art emphasising seaweed biofiltration in modern mariculture. Aquaculture 231, 361-391 Elsevier Pub. Neori, A., Msuya, F., Shauli, L., Schuenhoff, A., Kpoel, K and Shpigel, M. (2003) A Novel Three-Stage Seaweed (Ulva lactuca) Biofilter Design for Integrated Mariculture. Journal of Applied Phycology 15: 543-553.

33

Nisizawa, K. (1987) Preparation and marketing of seaweeds as foods. In ‘Production and Utilisation of Products from Commercial Seaweeds’ Edited by D.McHugh FAO Fisheries Technical Paper 288. Nisizawa, K. (2006) Seaweeds Kaiso Bountiful Harvest from the Sea. In Seaweed Resources of the World (Critchley, A. T., Ohno, M., Largo, D.B. editors). Japan International Cooperation Agency, Yokosuka. Norziah,M.H and Ching,Ch.Y. (2000) Nutritional composition of edible seaweed Gracilaria changi. Food Chemistry 68, 69-76. Partidge,G.J., Lymberry,A.J and George,R.J. (2007) Finfish mariculture in inland Australia: A review of potential water sources, species and production systems. Journal of World Aquaculture Society (Pre-publication advanced copy). Paul, V.J., Puglisi, M.P., and Ritson-Williams, R. (2006) Marine Chemical Ecology J. of the Royal Society of Chemistry. Natural Product Report. 23, 153-180 (www.rsc.org/npr). Philp, K. and Campbell, R. (2006) Hydrocolloids from Seaweed Resource In: Seaweed Resources of the World (Critchley, A. T., Ohno, M., Largo, D.B. editors). Japan International Cooperation Agency, Yokosuka. Qin, J. (2005) Bio-Hydrocarbons from Algae. RIRDC Report SQC-1A. Saker, K.E., Fike, J.H., Veit, H and Ward, D.L. (2004) Brown Seaweed (Tasco) treated conserved forage enhances antioxidant status and immune function in heat-stressed wether lambs. J. Animal Physiol. A. Anim. Nutr.88, 122-130. Sanderson, J.C. and Di Benedetto, R. (1998) Tasmanian Seaweeds for the Edible Market. Technical Report 32. Department of Sea Fisheries, Tasmania Marine Laboratories. Sanchez-Machado, D.I., Lopez-Cervantes, J., Lopez-Harnandez, J and Paseiro-Losada, P. (2004) Fatty acids, total lipd, protein and ash contents of processed edible seaweeds. J. Food Chemistry 85, 439-444. SEAFOODplus www.seafoodplus.org Shpigel, M (2006) Constructed Wetlands with Salicornia as an Environmentally Friendly Biofilter and a Valuable By-Product in Landbased Facilities. World Aquaculture Society. AQUA 2006 Meeting Abstract 378. Smayda, T.L. (1989b) Novel and nuisance phytoplankton blooms in the sea: evidence for the global epidemic. Toxic Marine Phytoplankton. Editors: Granelli, Sundstrom, Edler, Anderson. Elsevier Science Pub. New York. Smit, A.J. (2004) Medicinal and pharmaceutical uses of seaweed natural products. A Review. Jnl of Applied Phycology, 16, 245-262. Stirk, W.A. and Van Staden, J. (2006) Seaweed Products as Biostimulants in Agriculture. In: Seaweed Resources of the World (Critchley, A. T., Ohno, M., Largo, D.B. editors). Japan International Cooperation Agency, Yokosuka. Teas, J. (2006) Dietary brown seaweeds and human health effects. In Seaweed Resources of the World (Critchley, A. T., Ohno, M., Largo, D.B. editors). Japan International Cooperation Agency, Yokosuka. Thomson, C.D. (2004) Selenium and Iodine Intakes and Status in New Zealand and Australia. British Journal of Nutrition. 91, 661-672.

34

Tran, H. (1996) Seaweed as a Source of Omega-3 Fatty Acids and Beta Carotene RIRDC Research Paper DAV-87A. Turner, J., Dritz., S.S, Higgins, J.J., and Minton, J.E. (2002) Effects of Ascophylum nodosum extract on growth performance and immune function of young pigs challenged with salmonella typhimurium. J. Animal Sci. 80, 1947-1953. U.S. Department of Energy’s Office of Fuel Development (1998) A Look Back at the U.S. Department of Energy’s Aquatic Species Program – Biodiesel from Algae by Sheehan, J, Dunahay, T, Benemann, J and Roessler, P. NREL/TP-580-24190. Wondu Holdings (2000) New Pharmaceutical, Nutraceutical and Industrial Products. The Potential for Australian Agriculture. RIRDC Report 00/173. Wong, K.H. & Cheung, P.C.K. (2000) Nutritional evaluation of some subtropical red and green seaweeds. Food Chemistry, 71, 475-482.