Article: Exploring Yogurt Powder -- December 2009
Media sources, from The New York Times to food andwine.com, frequently tout yogurt as a supfood1,2. Food manufacturers who want to capitalize on the healthy halo of yogurt, but who do not have the facilities to handle regular yogurt or cultured fluid milk, can look to yogurt powder as an ideal way to include some of the flavor and nutrition of yogurt in their next introduction.
After numerous requests from food manufacturers for more information about yogurt powder, Dairy Management Inc. conducted a research project at the Southeast Dairy Foods Research Center to explore functional properties and consumer perception of yogurt powders. This project was initiated in 2008, and a poster was presented at the 2008 IFT Food Expo3. Recently, an ingredient fact sheet was published to share the findings of this research more widely with the industry.
Yogurt powder can be used in a wide variety of food applications, including snacks, confections, bakery items and breakfast cereals. Some of the more interesting product introductions include shelf-stable desserts, ice cream bars and fruit-yogurt dressings4. But the list does not stop there. Yogurt powder also can be found in a yogurt-raspberry baby cereal, a curry vegetable soup, a white chocolate gourmet brownie, a frozen chicken risotto entrée, an Indian bread and a chewable vitamin tablet. At this year’s IFT Food Expo, DMI presented a yogurt-dipped peach snack bar. Yogurt powder is often used in compound coatings that enrobe snack bars and nutrition bars.
There are no standards of identity for yogurt powder, and products are typically sold as “dehydrated yogurt,” “non-fat yogurt powder” or “cultured dairy solids.” DMI’s research found that the products currently on the market fall into two distinct categories. Traditional yogurt powder is manufactured by adding cultures to non-fat milk, allowing the product to reach a specified pH and then drying. These products typically have a protein content of 33-36%. Cultured dairy solids are often a blend of dairy ingredients, and protein content of this group typically falls between 22-33%. Ingredients found in the latter group included cultured non-fat milk, cultured whey, cultured whey protein concentrate, cultured dairy solids, non-fat dry milk, whey powder, lactic acid, natural and artificial flavors, and silicon dioxide as an anti-caking agent.
The functional properties of yogurt powder and cultured dairy solids can exhibit significant variation. Research at the SDFRC evaluated six domestic yogurt powders for color, pH, titratable acidity and foaming capability. Product pH can be an indicator of tartness. Samples tested ranged from pH 4.7-5.1. Titratable acidity is a measure of the lactic acid present in a dairy product or ingredients, and ranged from 5.8-7.4%. Some manufacturers add lactic acid as an ingredient to yogurt powder.
Foaming can be a desirable attribute in a raspberry yogurt smoothie mix that consumers shake up at home, and an undesirable attribute in an RTD beverage line where manufacturers want to minimize foaming at the filler. There was significant variation in the amount of foam produced after whipping for 20 minutes, but none of the six samples tested produced stable foams. DMI applications specialists can assist food manufacturers in identifying the yogurt powder with the most desirable attributes for their specific application.
DMI has an extensive formula library that includes beverages, salad dressings, dips, frostings, chews and compound coatings. Formulas incorporate regular yogurt, yogurt powder and/or cultured skim milk. “When substituting yogurt powder for fresh yogurt, start by comparing the solids of the two ingredients,” suggests K.J. Burrington, director of Dairy Ingredient Applications at the Wisconsin Center for Dairy Research. In dip applications, yogurt powder will not provide the same viscosity as fresh yogurt. Some formula adjustments, such as the addition of stabilizers to increase viscosity, may be necessary.
In the sensory portion of the research, consumer acceptance of yogurt powder was tested in strawberry drinkable yogurt, a white compound coating and a yogurt vegetable dip. “Hedonic scores suggest that a mildly flavored yogurt powder was best liked in the beverage application, perhaps due to a more natural dairy aroma,” notes MaryAnne Drake, Ph.D., and director of the DMI Sensory Applications Lab.
Usage levels of yogurt powder will vary by application. A 14g serving of yogurt powder (with 35.9g protein and 1,255mg calcium per 100g) will provide a good source of protein (5g) and a good source of calcium (175mg). Serving size and desired flavor profile also can impact usage levels.
As the popularity of yogurt continues to rise, the addition of yogurt powder offers food manufacturers an excellent opportunity to leverage a growing category. One of the most compelling reasons to add yogurt powder to the next formulation is the power of the word “yogurt.” pf
1 http://topics.nytimes.com/top/news/health/series/recipes_for_health/yogurt/index.html August 2008.
2 www.foodandwine.com/articles/yogurt-the-new-supfood November 2008.
3 Jessica Childs and MaryAnne Drake. Sensory properties of yogurt powders, poster presentation, IFT annual meeting, June 2008. Abstract 048-09.
4 Mintel’s Global New Products Database.