Composition and consumer acceptance of frozen yogurts utilizing whey protein concentrates.
Whey protein concentrate and a new fermented whey protein concentrate were used to replace the milk SNF in from yogurt. Fermented whey protein concentrate was manufactured by fermenting liquid whey protein concentrate with a commercial culture of Lactobacillus delbrueckii ssp. bulgaricus andStreptococcus salivarius ssp. thermophilus. Frozen yogurt mix contained 6% milk fat, 10.5% whey protein concentrate (100% SNF replacement), 11% sucrose, 3% corn syrup solids, .3% stabilizer and emulsifier blend, and 30.8% total solids. The mix was pasteurized (72°C for 30 min) and cooled to 4°C. Fermented whey protein concentrate (3.1% by weight of mix) was then added for a final titratable acidity of .43%. Frozen yogurt mix was divided into three equal batches, which were manufactured into vanilla, strawberry, and chocolate frozen yogurt. The frozen yogurts were evaluated from questionnaires filled out by 1005 attendees of the Meeker County Fair in Litchfield, MN. Those surveyed were 43.5% males and 56.5% females, ranging in age from 6 to 89 yr. Overall, 87.8% (83.5% of the males and 91.5% of the females) liked the test product, and 81.2% (72.4% of the males and 88.2% of the females) said they would buy this product if it were priced the same as ice cream. Results indicate that an acceptable frozen yogurt can be produced when 100% of the milk SNF is replaced with whey protein concentrate and fermented whey protein concentrate.