Effect of Whey Protein Concentrate on Physicochemical, Sensory and Antioxidative Properties of High-Protein Fat-Free Dairy Desserts

This study evaluates a new formula for high-protein fat-free dairy desserts. The rheological, textural, organoleptic and antioxidative properties of this product have been examined. They were prepared in laboratory conditions using a magnetic stirrer and then mixed in a water bath at 80 °C for 10 min. The composition included skimmed-milk powder, different concentrations of whey proteins (WPC80) (5, 7, 9, 11 or 13%), sucrose and ĸ-carrageenan. Samples were stored at 4 °C. The use of different amounts of whey proteins significantly influenced the texture, rheological properties and appearance of dairy desserts. With the increase of WPC80 content, the hardness (5–11%), adhesiveness (5–13%), cohesiveness (513%), springiness (5–11%) and viscosity (5–13%) of the high-protein fat-free dairy desserts increased. Elastic (gel) properties were exhibited throughout the process (G’ > G”). This result was confirmed by the measurements of tan(δ) (tan(δ) < 1). Water activity decreased with an increase in WPC80 content. Health-promoting features using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) measurements were evaluated. Both methods showed that the samples have antioxidant properties. Panelists described desserts with 9% WPC80 as the most favorable according to sensory properties. This research promotes the reduction of production waste using high-protein whey powder, a by-product of whey from cheese manufacturing, as a main component during food production, and it also promotes fat-free food.