Physicochemical and sensory properties of protein-fortified cookies according to the ratio of isolated soy protein to whey protein.

A high-protein diet has a variety of beneficial effects and mixing isolated soybean protein (ISP) with whey protein (WP) reported to increases health and functional advantages. The objective of this study was to determine an adequate ratio for mixing these two proteins by evaluating the physical and sensory properties of protein-fortified samples. Samples with 5 different ratios of ISP to WP ranging from 100:0 to 0:100 were prepared. Proximate composition, density, spread factor, hardness and color values of five samples were measured and consumer acceptance test were conducted by 117 panelists to evaluate physicochemical and sensory properties of protein-fortified cookies. In a consumer acceptance test, the combination of ISP and WP increased consumer acceptance, and the highest overall acceptance was obtained when ISP and WP were used in a one to one ratio. As the ISP content increased, the density was higher, and the spreadability was the lowest. On the other hand, as WP increased, hardness increased significantly, and L*, a* and b* values increased (p < 0.05).The result of this study may facilitate the development of protein-enriched foods, which have various health benefits. © The Korean Society of Food Science and Technology 2021.