Ingredient and Taste img

Key Points

  • Manufactures of dairy products such as yogurt, flavored milk and ice cream are increasingly relying on stevia as an option for low-sugar formulations
  • Stevia can be incorporated alone or in combination with sugar or other high-intensity sweeteners
  • Specific combinations of steviol glycosides can be optimized to enhance creamy dairy notes while reducing off-notes such as bitterness and licorice

Dairy has traditionally presented complex challenges for formulators looking to reduce sugar while maintaining texture, indulgence and mouthfeel. Furthermore, when it comes to reducing sugar in dairy, stevia is a great choice since it is stable throughout the pasteurization process required in many dairy products. This article will discuss the taste and functional benefits of incorporating stevia into a variety of dairy applications including yogurt, flavored milk and ice cream.

Yogurt

There is strong consumer demand for dairy products that help promote a healthy lifestyle. The largest growth category within the dairy market is yogurt, with a 7.4% increase in sales from 2015 to 2016, according to Euromonitor International.1 Reduced-calorie, reduced-sugar and reduced-fat platforms, or a combination of the three, are appearing more frequently among new yogurt product introductions and stevia plays a large role. In 2016, 273 dairy products were launched globally with stevia and of those, 70% were yogurt.2

A sensory study of reduced-sugar strawberry flavored yogurt found that up to 50% of the sugar (sucrose) in fresh yogurt could be substituted with stevia (rebaudiana A) without any perceivable change in taste. However, sugar reductions of 75% with rebaudiana A yielded noticeable bitterness and astringency, as well as a reduction in sweetness intensity.3

Stevia can provide a synergistic effect in yogurt applications along with other high-intensity sweeteners. A study of strawberry flavored yogurt determined the sweetness concentration of several high-intensity sweetener combinations equivalent to 11.5% sugar. Findings showed that a formulation made with a cyclamate/saccharin/stevia combination presented greater sweetening power than one with just cyclamate/saccharin.4

Flavored Milk

Flavored milk, such as chocolate milk, is a popular and regularly consumed beverage, with wide sensory acceptance among consumers of different age groups and socio-economic levels.5 Milk is an excellent source of calcium, vitamin D, riboflavin and phosphorus, and a good source of protein, potassium, vitamin A, vitamin B12 and niacin6. Studies show that children who drink flavored milk consume more milk overall and are better nourished.7 Unfortunately, flavored milk is also high in added sugars, and has been scrutinized in light of increasing trends of overweight and obesity in children.

Using stevia is an attractive option for reducing the sugar content of flavored milk. In a study on attributes that influence the purchase of chocolate milk by parents for their children, type of sweetener was the primary driver of purchase followed by fat content. Among sweetener types, parents preferred natural, non-nutritive sweeteners or sugar over artificial sweeteners.8

It is important to maintain consumer acceptability, especially for children, while reducing sugar in chocolate milk. A study of the perceived sweetness intensity of stevia leaf and monk fruit extracts in non-fat chocolate milk found milks sweetened 100% by non-nutritive sweeteners were less acceptable compared with the full-sugar control by young adults aged 19-35 y. However, the overall liking was not different for 100% sugar-sweetened chocolate milks compared with a 25% sugar reduction using a blend of sugar and stevia or monk fruit. These 25% sugar reduced non-fat chocolate milks were acceptable to both young adults and children aged 8-13 y. Interestingly, a greater percent of children 5-7 y showed a preference for the 25% sugar-reduced chocolate milks over the 100% sugar-sweetened, non-fat chocolate milk (percent of children who preferred: sugar, 23%; stevia, 40%, monk fruit 37%).9

Formulation of flavored milk with stevia present unique opportunities to the development process. Combinations of steviol glycosides tend to work best for larger sugar reductions, and stevia natural flavors can enhance cocoa and dairy notes. Since sugars provide mouthfeel, low-sugar formulations made with stevia can use thickening agents and complex carbohydrates.10

Ice Cream

Ice cream is the world’s most popular frozen dessert. The sweeteners used in ice cream have an important influence on consumer acceptance due to their effect on texture and functionality (freezing point, viscosity and texture).11 For economic and functional reasons, sucrose (sugar) is the most frequently used sweetener in ice cream production. However, the use of non-nutritive sweeteners is increasing due to health concerns about ice cream’s high-sugar content.

Stevia’s natural label is an attractive option for consumers seeking a lower-sugar ice cream. A recent study of five ice cream formulations produced using different proportions of sucrose and stevia presents considerations for stevia’s usage in ice cream.12 Results found replacing sucrose with stevia resulted in a significantly lower viscosity and brix with a higher overrun and melting rate in a dose dependent manner. Furthermore, mixtures containing both sucrose and stevia had higher sensory acceptance than those sweetened entirely with stevia. Similar results were found in kulfi, a traditional frozen Indian dessert that is similar to ice cream.13 Kulfi prepared by replacing half the sugar content with stevia was similar to the full-sucrose control in sensory characteristics. However, formulations with greater than 50% sugar replacement resulted in bitterness, altered appearance and presence of an icy texture.

Emerging Technology

What works in a carbonated soft drink is not necessarily going to be the right solution for an acidified or sweet dairy product. The next generation of stevia for dairy applications involves the development of specific combinations of steviol glycosides optimized to enhance creamy dairy notes while reducing off-notes such as bitterness and licorice.

Sigma-D, a proprietary ingredient from PureCircle®, contains optimized steviol glycoside combinations to overcome technical hurdles typically found in no sugar added dairy products, such as delayed sweetness and sweet linger. It works well in mid-calorie reductions, and shows excellent synergy with other nutritive sweeteners such as sucrose (sugar). It is also stable through HTST (high temperature short time) and UHT (ultra-high temperature) processing.

Sigma-D demonstrates parity to sucrose and preference over rebaudiana A on key attributes.14 In a sensory study of chocolate milk, an 80% reduced-sugar formulation made with Sigma-D was parity on key sensory attributes to a full-sugar control while outperforming rebaudiana A (see figure 1). Similar results were seen in flavored yogurt (figure 2).14

Conclusion

Stevia is a valuable ingredient to reduce sugars in dairy applications. Its many benefits include superb functionality, stability and flexibility of use in a wide variety of dairy categories such as yogurt, flavored milk and ice cream. Category-specific stevia solutions allow deeper sugar reductions while preserving true flavor and superior mouthfeel.


REFERENCES

  1. Euromonitor International. Report: Dairy in the US. 2016. http://www.euromonitor.com/dairy-in-the-us/report
  2. Mintel. Global New Products Database: CPG and FMCG. Mintel Group Ltd. 2016. Available at: http://www.mintel.com/global-new-products-database
  3. Hergesell L, et al. Possibilities and limitations of sugar reduction by steviol glycosides in yoghurt. Ernahrungs Umschau. 2014;61:181-7.https://www.ernaehrungs-umschau.de/english-articles/15-12-2014-possibilities-and-limitations-of-sugar-reduction-by-steviol-glycosides-in-yoghurt/
  4. Reis R, et al. Sweetness equivalence of different sweeteners in strawberry‐flavored yogurt. J Food Qual. 2011;34:163-170. https://doi.org/10.1111/j.1745-4557.2011.00378.x
  5. Paixão J, et al. Influence of temperature and fat content on ideal sucrose concentration, sweetening power, and sweetness equivalence of different sweeteners in chocolate milk beverage. J Dairy Sci. 2014;97:7344-53. https://www.sciencedirect.com/science/article/pii/S0022030214007553
  6. Krebs-Smith S, et al. Americans do not meet federal dietary recommendations. J Nutr. 2010;140:1832-8. https://doi.org/10.3945/jn.110.124826
  7. Johnson R, et al. The nutritional consequences of flavored-mild consumption by school-aged children and adolescents in the United States. J Am Diet Assoc. 2002;102:853-6. https://doi.org/10.1016/S0002-8223(02)90192-6
  8. Li X, et al. Extrinsic Attributes That Influence Parents’ Purchase of Chocolate Milk for Their Children. J Food Sci. 2014;79:S1407–15. https://doi.org/10.1111/1750-3841.12515
  9. Li X, et al. Parents’ and Children’s Acceptance of Skim Chocolate Milks Sweetened by Monk Fruit and Stevia Leaf Extracts. J Food Sci. 2015;80:S1083–92. https://doi.org/10.1111/1750-3841.12835
  10. Homayouni A, et al. Effect of inulin and stevia on some physical properties of chocolate milk. Health Promot Perspect. 2012;2:42-7. http://hpp.tbzmed.ac.ir/Abstract/HPP_73_20120701115016
  11. Land D. Perspectives on the effects of interactions on flavor perception: An overview. ACS Sym Ser 1996;633:2-11. https://pubs.acs.org/doi/abs/10.1021/bk-1996-0633.ch001
  12. Alizadeh M and Azizi-Lalabadi M. Impact of using stevia on physicochemical, sensory, rheology and glycemic index of soft ice cream. Food Nutr Sci. 2014;5:390-96. http://file.scirp.org/Html/12-2701110_42783.htm
  13. Giri A, et al. Effect of partial replacement of sugar with stevia on the quality of kulfi. J. Food Sci Technol. 2014;51:1612-6. https://doi.org/10.1007/s13197-012-0655-6
  14. PureCircle Inc. Internal sensory study report. PureCircle, 2016.