importance of lipid analysis, research and development in .... raymond thomas.pdf · importance of...
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Importance of Lipid Analysis, Research and Development in Food Quality Evaluation
By
Dr. Raymond Thomas
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Dr. Raymond Thomas
Associate Professor in Environmental Science
But trained:
Analytical Chemist/Plant Scientist/Biochemist/Neurochemist/Agriculturist/Food
Scientist
Environmental Science and Boreal Ecosystem Research Facility
Grenfell Campus, Memorial University
Who am I ?
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What I do!
◼ Pressurized solvent & liquid-liquid extraction:
◼ Accelerated solvents, supercritical fluids, Bligh&Dyer, Folch
◼ Chromatographic
◼ SPME, liquid, thin layer, gas, ion, SPE and column)
◼ Mass spectrometry
◼ HESI-MS/MS, GC-MS/FID, DESI-MS,
◼ Study LIPIDS in
◼ Food/health science, biology, agriculture, neurobiology
I use specialized analytical techniques:
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Research interests
◼ Development of novel or enhanced analytical techniques to better understand the roles of lipid metabolism in functional foods production, development, preservation and safety
Fall under 3 themes:
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Lipids◼ Are fats
◼ Monomers are generally glycerol and fatty acids joined together by ester bonds
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Fatty acids (FA)
◼ Building blocks of complex lipids
◼ Characteristics COOH functional group
◼ Saturated (animals) and unsaturated (plants)
(Mono vs Poly, (trans vs cis- occur natural)
◼ Odd or event numbered (C2-C26)
◼ Modified (hydroxylated, methylated, dicarboxylated, etc)
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Classification Scheme
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Complex lipids and their structural relationship
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Function of Lipids in food
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Fats and food stability
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HYDROGENATION AND FOOD TEXTUTURE
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HYDROGENATION AND SHELFLIFE
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Phospholipids as food emulsifiers
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Plant sterols as functional ingredients
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Essential fatty acids must be obtained from food
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Food sources of essential fatty acids
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Omega Fatty Acids in Food
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Good sources of omega 3
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Dietary Intake of Food Lipids
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Dietary Intake of Food Lipids
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Why is it important to analyze lipids in food?
Indicator of food quality
Determine shelf life
Determine sensory quality (texture, taste, aroma, consumer preference)
Source of functional ingredients
Provide branding opportunity based on nutritional and health benefits
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Examples of lipids as functional ingredients
◼ Omega-3 fatty acids
◼ (alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA)),
◼ Omega-6 fatty acids
◼ (gamma linoleic acid (GLA), and linoleic acid (LA)),
◼ Conjugated
◼ linoleic and linolenic acid (CLA/CLN),
◼ Medium chain triglycerides
◼ Phytosterols
◼ Plasmalogens
◼ Diglycerides
◼ Vitamins
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What are functional foods?
◼ Natural or processed foods/products
◼ Have bioactive ingredients with demonstrated health benefits beyond basic nutritional needs
◼ Examples of functional food components
◼ Antioxidants:
◼ Phenolics, vitamins C & E
◼ Lipids: (ω3 and ω6),conjugated
fatty acids
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FUNCTIONAL FOODS CHARACTERISTICS
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Why the interest in functional foods?
◼ Functional foods: Emerging field in food science (biggest industry food trend in next 10 yrs)
◼ Driven by a health conscious consumers who recognise
the benefits between healthy diets and enhanced health
◼ Global market = $176 billion at 15% annual growth
◼ $780 million industry in Newfoundland
◼ $30 billion industry in Canada ( Statistics Canada 2013) (www.agr.gc.ca)
◼ As Agriculture and Food Sector Grow in the Province
◼ Opportunities exist to produce functional foods unique to NL
◼ Supply Niche functional foods market/enhance health of locals◼ create new interest in existing products or develop new products
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How can the functional food research program help:
◼ Through Applied research partnerships
◼ New Functional Foods Research Program on Grenfell Campus at Memorial University
◼ We use hypothesis driven question to help solve industry driven questions within our expertise and capabilities
◼ Secondary product development/food innovation/functional foods development/create new knowledge
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Functional Foods Research benefits to industry
◼ Create new or improved products or processes
◼ Create new uses or new interests in existing products
◼ Create value added or secondary products
◼ Preserve functional components present in existing, new or enhanced products
◼ Enhance the quality and shelf life of existing, new or enhanced products.
◼ Sensory Evaluation of functional foods and other food products
◼ Health benefits/bioactivity assessment
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Relevance & unique opportunity
◼ NL have unique climate
◼ Climate influence chemical composition and levels of functional components
◼ Plants, animals and microbes with unique composition
◼ Opportunities to develop functional foods/secondary products unique to NL for the functional foods market branded as unique NL products
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Example of a Potential Unique NL Functional Product
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Why Functional Foods
◼ Challenges:
◼ NL has the highest mortality due to:
◼ Hearth disease
◼ Stroke
◼ Cancer
◼ Diabetes
◼ Opportunities:
◼ Diet is the biggest factor that can be used to change health outcome and reduce disease risks
◼ Potential innovation, research collaboration, product development in functional foods/food products
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Examples of functional foods and components
Yogurt enhanced with probiotics
Blueberries high in
antioxidants and polyphenolics
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Functional Foods Research Program at Grenfell
◼ New Program
◼ Have
◼ 2 PDF
◼ 5 PhD students
◼ 5 MSc students
◼ 4 Undergraduates
◼ 3 years old
◼ Functional Foods Sensory Lab and BERI host facility for the research program and student training
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Functional Foods Sensory Laboratory Integrated within the Boreal Ecosystem
Reseach Facility
Infrastructure Unique to Atlantic Canada
Enhance functional foods development and research in
the region
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Capacity and Equipment of Facility
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BERI Consist of a Suite of 4 Environmental
Labs
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Lab 1: Pre-Process Lab◼ Primary function
◼ Preliminary sample
processing and storage
◼ Major equipment◼ Walk in cooler/freezer
◼ Drying ovens/incubators
◼ Autoclaves
◼ Centrifuges
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Lab 2: Extraction and Chemical Analysis◼ Primary function
◼ High efficiency sample
extraction
◼ Major equipment◼ Accelerated solvent extractor◼ (extraction of solid and semisolid sample
matrices)
◼ Supercritical fluid extractor◼ (Extraction of solid and liquid
◼ sample matrices)
◼ Rotavapor/distillator
◼ Ultra sonic wave extractor
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Lab 3: Molecular Biology Lab
◼ Primary function◼ Genetic: RNA, DNA analysis
◼ Tissue and cell culturing
◼ Food quality and microbiology
◼ Major equipment◼ Digital droplet DNA and RNA
quantifier
◼ Real time thermocyclers
◼ Bioreactors/fermentors
◼ Flow cytometer
◼ Bioinformatic system
◼ -80 ultra low freezer
◼ Media clave
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Lab 4: Analytical Chemistry◼ Primary function
◼ Analyze inorganic and organic
analytes from any sample type
(solid, liquid or gas)
◼ Major equipment◼ Gas/liquid/ion chromatographs
◼ UV-VIS, CD,ECD, Florescent
◼ Mass spectrometers
◼ ESI, DESI, APPI, APCI modes
◼ Raman and FTIR microscopes
◼ NIR feed/food analyzer
◼ Spectrophotometers
◼ Flame ionization detectors
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Laser ablation-inductively
coupled plasma-mass
spectrometer (LA-ICP-MS)
Enable multi-elements
trace analysis and
isotope ratios in samples
LA-ICP-MS used to
produce spatial
distribution (images) of
specific elements in
sample tissue sections
ICP-MS to be coupled
with the IC
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New Functional Foods Sensory Laboratory
Built in collaboration with Industry
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Food Lipid Chemical Imaging :
Confocal Raman, FTIR and laser scanning
microscopes
Imaging mass
spectrometry
DESI-MS + Orbitrap
Laser ablation
inductively
coupled plasma
mass
spectrometry
Multimode reader
Cytation cell imager
Gierlinger 2006, Becker 2007, Dill 2011,
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Functional Food Sensory Laboratory and Program
◼ Capacity:
◼ Food sensory quality evaluation
◼ Functional Food formulation and development
◼ Food quality assessment
◼ Food lipid analysis
◼ Food shelf life evaluation
◼ Food Innovation
◼ Functional ingredients analysis
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Research collaboration
◼ Facility is open to anyone interested in collaborative research as well as fee for service analysis to assist with food automation, development or analysis
◼ Examples of current collaborations
◼ Business/industry
◼ Mun faculty
◼ Government
◼ International
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Questions
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Dietary sources of functional lipids
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What is lipidomics◼ Omics science concerned with the comprehensive
identification and quantification of cellular lipids and their function in biological systems