Effect of Sugar replacement with Stevia on Physical and Sensory Characteristics of Ice-Cream

Goutham Matta

Grant Agency and Program:USDAFunding title: Agriculture and Food Research Initiative - Foundational ProgramAFRI grants to support research in six Farm Bill categories: My grant topic comes under Food safety, nutrition, and health Category.

Ice-Cream Facts:About 1.53 billion gallons of ice cream and related frozen desserts were produced in the U.S.U.S. ice cream companies made more than 872 million gallons of ice cream in 2015. The average American consumes almost 22 pounds of ice cream per year.40% of Americans will eat ice cream that’s nearly as large a share as will drink coffee (47%).Ice cream is consumed regularly. Children 6-12 years of age have the highest uptake (62%), followed by adults over 75 years of age (58%). 

Stevia Facts:Stevia Rebaudiana Bertoni (commonly called stevia) is a member of the Chrysanthemum family. Stevia is a natural herbal sweetener with no calories and no carbohydrates.What makes stevia leaves sweet are two glycosides stevioside and rebaudioside. Rebaudioside A (Reb A) is the sweetest and purest extract of the stevia leaf.Rebaudioside A is approximately 250 to 300 times sweeter than sucrose.In the US, rebaudioside A is Generally Recognized As Safe (GRAS) for use as a general purpose sweetener and may be used in foods and beverages, excluding meat and poultry products. The Joint FAO/WHO Expert Committee on Food Additives (JECFA) defines Acceptable Daily Intake (ADI) of stevia is (standard human = 4mg/kg body weight per day).Stevia sweeteners are metabolized by a common pathway. Once consumed, it is broken down in the gut and then rapidly eliminated from the body.

Stevia Facts:The Stevioside has a liquorish aftertaste while Rebaudioside-A has no liquorish or aftertaste. Rebaudioside A can be further filtered and purified up to 99%. That’s why Rebaudiana A is more expensive. The more purified and concentrated the less bitter and more sweeter it is. Stevioside has an aftertaste even if it is 99% purified, but Rebaudioside A does not possess an aftertaste and has a sweetness flavor comparable to sugar.Carakostas et al. (2008) conclude that high purity rebaudioside A produced to food-grade specifications and according to GMP is safe for human consumption under its intended conditions of use as a general purpose sweetener.

Abstract:Ice cream contains high sugar content and therefore it is in contradiction with the concept of healthy diet. The objective of this study is to determine the suitability of using stevia as an alternative natural sweetener in making ice cream. Control Ice-cream formulation and three different concentrations of stevia ice cream formulations were used. Physical properties of the ice cream such as the overrun, total soluble solid, meltdown rate, rheology, and textural properties were evaluated. Sensory evaluation were determined based on the level of pleasure or displeasure

Specific Aims:The Impact of sugar replacement with stevia on physical and sensory characteristics of ice-cream and to introduce a novel stevia based ice-cream.To figure out what is the most appropriate stevia concentration for replacing sugar in ice cream without affecting the physical and sensory characteristics.

Hypothesis:Sugar replacement with stevia will not have any effect on physical and sensory characteristics of ice-cream.

Research Strategy:Significance:Despite of high prevalence of obesity and Type 2 diabetes among children and adults, people are now more conscious of their health status and subsequently aware of their eating regimen. As a result, the ice cream market trend is moving towards a low calorie, low sugar ice cream formulation and with excellent texture and sensory properties to gain the consumers’ satisfaction. “Ice cream sweetened with safe and suitable sweeteners and may be characterized by the addition of flavoring ingredients” (FDA 2015).Higher intake of added sugars is associated with higher energy intake and lower diet quality, which can increase the risk for obesity, pre-diabetes and type-2 diabetes. Therefore, it is necessary to use alternatives to reduce the sugar content in their products, such as natural and artificial sweeteners (ACADEMY OF NUTRITION AND DIETETICS, 2012).

Research Strategy:Innovation:Consequently, a number of studies had been carried out in developing new functional ice creams with ingredients such as dietary fibers, probiotics, low glycemic index sweeteners and alternative sweeteners such as xylitiol, sorbitol, and maltitol. Mainly, these innovative ice creams were made using artificial sweeteners. There are few studies done using natural sweeteners in ice cream production. Therefore innovative aspect of this project is to completely replace the sugar with stevia in ice cream with different proportions and the check the physical and consumer acceptance of it to make it commercially available in the market.

Preliminary Studies:Consumers acceptance of low-calorie foods:

Drewnowski et al., (2015) Low calorie sweeteners use was more common among populations with a lower burden of obesity and related chronic disease, specifically, non-Hispanic whites and those with more education/higher incomes.

Piernas et al., (2012). Purchases and consumption of CS products were declining, documented an increasing trend in products that contain LCS, especially important among households with children.

Gregory et al., (2014) Making a low calorie food more proximate will reduce total energy intake and increase intake of a low calorie food, even when a higher calorie and more preferred food is also available, but less proximate.

Paul et al., (2012) Availability of lower-calorie foods is increased and is also combined with labeling and reduced prices, students make healthier choices without buying more or fewer products from school vending machines.

Preliminary Studies:Stevia- A low calorie Sweetener:

Saurabh et al., (2015) Stevioside made from stevia leaves can be used to make various food products for sweetening purposes, which could be a boon to diabetic patients who are barred from taking sugar.

Katarzyna et al., (2015) Stevia Rebaudiana Bertoni has an increasingly extensive range of applications worldwide, not only as a sweetener, but also as a food additive reducing energy value of food stuffs.

Jorge et al., (2015) The polar compounds obtained during the extraction like chlorophylls, carotenoids, phenolic compounds and flavonoids contribute to the antioxidative activity measured. The leaves of S. Rebaudiana Bertoni could be used not only as a source of non-caloric sweeteners but also naturally occurring antioxidants.

Preliminary Studies:Stevia replacing sugar in ice-cream:

Mohammad et al., (2014) Reported that stevia in combination with sugar resulted in low viscosity, high overrun and best sensory acceptance. Sugar with Stevia may be a choice to produce low caloric and GI ice creams.

Pon et al., (2015) Stevia ice cream has a lower melting rate and has a higher sustainability. The power law also showed that apparent viscosities of stevia ice cream were higher. Therefore, stevia can be used as a natural sugar substitute in ice cream production.

Irma et al., (2016) Sensory evaluation showed significant differences between the control group (Ice cream with sugar) and Experimental (Sugar and Stevia ice cream) obtained, however all of them with a score above the indifference point suggesting that those products would have a potential to be commercialized.

Ice Cream Formulation:Receiving of milk

Figuring of mix

(milk, cream, SMP, sugar (control), stevia (experimental), stabilizer)

Making the mix

Pasteurization of mix (68°C for 30 min.)

Homogenizing the mix (210-240 psi for 5 mins.)

Cooling mix at room temperature

Flavors Blending

Blending of mix (90 sec.)

Freezing of mix (-4 to -5°C)

Packaging

Storage at -5°CSource: De and Ray (2000)

Ice Cream Formulation:Ingredients (%) Formulation

Control A B C

Full Cream Milk 72.0 83.2 82.8 82.3

Non-Fat Milk Solid 4.8 5.6 5.5 5.5

Butter 8.2 9.4 9.4 9.3

Sugar 14.0 0.0 0.0 0.0

Stevia Powder 0.0 0.6 1.1 1.7

Lecithin 0.4 0.5 0.5 0.5

Water 0.6 0.7 0.7 0.7

Methodology:Experimental ice creams will be prepared using the following process with three different proportions of stevia replacing sugar. Ice cream formulation of A, B, and C equivalent to sugar of 0.6, 1.1 and 1.7, respectively, will be used since 1 g stevia powder is equivalent to sweetness provided by 14 g sugar. Milk and water will be heated using a jacketed kettle to 65 ± 1°C. Non-fat milk powder and lecithin are weighed and mixed before pouring into the heated milk. The mixtures will be stirred, and melted butter will be added. The mixtures will be pasteurized at 65 ± 1°C, held for 30 minutes and then homogenized at 210-240 psi for 5 minutes using a high speed homogenizer. The ice cream mixes will be aged for 24 hours at 4 ± 1°C in a stainless steel container. They are then transferred into a hard ice cream maker and will be whipped until cool. When the ice creams’ temperature reaches 5.5°C, they will be drawn out from the machine to be filled into 220 ml polypropylene cups and should be carefully leveled to avoid compaction in order to prevent the air from being displaced from the pores otherwise ice cream becomes hard as this will affect the texture profile analysis. The ice creams will be transferred to the blast freezer to be hardened at -18°C. Ice creams will be stored for five days in a cabinet freezer (-18°C) before being analyzed.

Methodology:Evaluating the physical properties of stevia ice-cream:Physical properties of the ice cream like meltdown (%), rheological properties, overrun (%), Total soluble solids, Hardness (N), cohesiveness, chewiness, springiness, and gumminess will be studied.Overrun percentage: On %= 100 (Wm - Wic)/Wic

(Wm (g) is the weight of a given volume of mix and Wic (g) is the weight of same volume of ice cream).Total soluble solid will be measured using a Palatte-style digital refractometer and ranged from 0% to 45% Brix. Texture analyzer (TA-XT2i, Stable Micro System, UK) will be used to determine the hardness, adhesiveness, cohesiveness, gumminess, and springiness of the ice cream.Viscosity and rheology will be measured using Rheometer.Meltdown of ice cream will be measured using, 80.0 ± 2 g of sample placed on a wire mesh attached to a graduated cylinder and maintained under a controlled temperature chamber at 25ºC. The dripped volume will be measured at a 10 minute intervals for a total of 45 minutes. The first drop time was measured as the volume drip per minute. The data recorded will be used to determine the melting rate (ml/minute).

Methodology:Evaluating the sensory characteristics of stevia ice cream:

When it comes to sensory analyses, ice cream has its own particularities like the ideal temperature of degustation ranging from 10 until 12ºC and a maximum of six samples for capture and absorption of sensory interactions.The participants will be of either sex, ranging in age between 20 and 50 years old, consisting of students and faculty of Food and Nutritional Sciences Department at the University of Wisconsin-Stout. Approximately 15g of each sample was placed in a 50ml disposable container which was coded with three-digit numbers, sealed and kept in a thermal box to maintain the samples’ temperature (approx. 10°C).The participants will evaluate appearance, odor, consistency, taste. and overall liking using a structured 9-point hedonic scale ranging from 1 (disliked it very much) to 9 (liked it very much).

Methodology:Statistical Analysis:

Data will be entered into an Excel spreadsheet and uploaded to SAS (version 9.4). Statistical analysis was conducted using SAS (version 9.4) to determine the means and standard deviation of the physical data and sensory data. An ANOVA will be conducted to determine statistical significance and Least Square Means test will be conducted to determine differences between means.

Expected Outcome:Ice cream developed replacing sugar with stevia will not effect the sensory and physical properties and will be similar to control ice-cream (with sugar).At the end of study accurate percentage of stevia required to formulate a perfect low calorie ice cream will be determined. As the study includes experimental group with three different formulations of ice-cream with stevia.Therefore, stevia can be used as a sugar substitute in formulating ice cream for the health conscious market due to the benefits stevia provides and can make it commercially available.

Potential Problems and alternative strategies:

Major challenge would be to create a great tasting ice cream product with zero sugar and zero fat. Which should be more appealing to convenience consumers.Cargill recommended a Lygomme blend (colloids obtained from raw materials) which is a stabilizer designed specifically for ice cream. Lygomme blends can provide freeze/thaw stability, smooth texture and creaminess, enhanced softness and volume, shape retention and crystal ice growth control.To provide sweetness, rebiana and erythritol can be used in combination to remove calories and to provide a satisfying sweetness. 

Food processing company

Timeline:Year 1 Year 2

1-6 months 6-12 months 1-2 months 6-12 months

Study Prep

Ice cream Formulation

Physical and Sensory analysisAnalyzing the data

The first six months will be dedicated to preparation for the study, including finalizing study-specific SOPs, ordering initial supplies and recruiting study personnel.Next six months will be dedicated to make trails of ice cream preparation with different proportions of stevia. Second year’s first six months will be used to analyze both the physical and sensory characteristics of ice cream.Next six months would be utilized to analyze the results and making comparisons between both control and experimental ice-creams using statistical software.

Budget:A. Total salaries, wages and fringe benefits: $29,0501. Research Associate at 100% time-1/2 year. $15, 000

Fringe benefits- At 27%-1 research Associate. $4,050

2 temporary workers at 30 hours per week for 6 months. $10,000

B. Non expendable Equipment (Price including Shipping) $28,661Homogenizer (SRH2000-25) $12,000

Batch Freezer $4,000

Palatte-style digital refractometer $1.275

Texture analyzer $6,160

Rheometer $3,000

Precision Balance $3,500

C. Materials and supplies: $5,200Raw materials $3,000

Computer Software $1,600

Test and Research Supplies $600

Budget:IceD. Travel: $2,500

E. Publication Cost: $300

F. All other Direct cost: $3,100

Advertising and screening- flyers, handouts and newspaper ads $600

Sensory Panelists- 5 members at $500 each $2,500

G. Total Direct cost $68,811

H. Indirect cost (0.25 of total direct cost) $17,202

I. Total amount of this request $86,013

References:Marcinek, K., & Krejpcio, Z. (2015). Stevia rebaudiana Bertoni: Health promoting properties

and therapeutic applications. J. Verbr. Lebensm. Journal Für Verbraucherschutz Und Lebensmittelsicherheit, 11(1), 3-8. doi:10.1007/s00003-015-0968-2

Alizadeh, M., Azizi-Lalabadi, M., & Kheirouri, S. (2014). Impact of Using Stevia on Physicochemical, Sensory, Rheology and Glycemic Index of Soft Ice Cream. FNS Food and Nutrition Sciences, 05(04), 390-396. doi:10.4236/fns.2014.54047

Pon, S.Y., Lee, W.J., & Chong, G.H. (2015). Texture and Rheological properties of stevia ice cream. International Food Research Journal, 22(4), 1544-1549 (2015)

Aranda-Gonzalez, I., Perera-Pacheco, M., Barbosa-Martín, E., & Betancur-Ancona, D. (2016). Replacing sugar with S. rebaudiana extracts on the physicochemical and sensory properties of strawberry ice cream. Cienc. Rural Ciência Rural, 46(4), 604-609. doi:10.1590/0103-8478cr20150505

Piernas, C., Ng, S. W., & Popkin, B. (2013). Trends in purchases and intake of foods and beverages containing caloric and low-calorie sweeteners over the last decade in the United States. Pediatric Obesity, 8(4), 294-306. doi:10.1111/j.2047-6310.2013.00153.x

Bos, C., Lans, I., Rijnsoever, F. V., & Trijp, H. V. (2015). Consumer Acceptance of Population-Level Intervention Strategies for Healthy Food Choices: The Role of Perceived Effectiveness and Perceived Fairness. Nutrients, 7(9), 7842-7862. doi:10.3390/nu7095370

Kocken, P. L., Eeuwijk, J., Kesteren, N. M., Dusseldorp, E., Buijs, G., Bassa-Dafesh, Z., & Snel, J. (2012). Promoting the Purchase of Low-Calorie Foods From School Vending Machines: A Cluster-Randomized Controlled Study. Journal of School Health, 82(3), 115-122. doi:10.1111/j.1746-1561.2011.00674.x

References:Goyal, S. K., S., & Goyal, R. K. (2009). Stevia ( Stevia rebaudiana ) a bio-sweetener: A

review. International Journal of Food Sciences and Nutrition, 61(1), 1-10. doi:10.3109/09637480903193049

Giri, A., Rao, H. G., & V., R. (2012). Effect of partial replacement of sugar with stevia on the quality of kulfi. J Food Sci Technol Journal of Food Science and Technology, 51(8), 1612-1616. doi:10.1007/s13197-012-0655-6 http://www.idfa.org/news-views/media-kits/ice-cream/ice-cream-sales-trendshttp://www.cityam.com/220727/which-countries-eat-most-ice-cream-world-heres-scoophttp://draxe.com/stevia-side-effects/http://www.cargillfoods.com/na/en/product-development/reduced-calorie/light-ice-cream/index.jsphttp://www.ift.org/Food-Technology/Past-Issues/2016/April/Columns/ingredients-ice-cream-ingredients.aspx?view=print&page=viewall

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