The aim of this paper was to examine the effect of different types of protein concentrates on rheological properties of set type yogurts. Yogurts were supplemented by addition of 1,2 or 4% of WPC35, 65WPC, WPC 85 and defatted WPC(WPCO). The process of yogurt fermentation was monitored with using of dynamic oscillation rheometry and following parameters such as: viscosity, hardness and gumminess were determined. In case of yogurt where no milk protein powder was added, the curd started to form after 126 minutes of fermentation. The addition of skimmed milk powder (SMP) decreased the curding time and it was 119 minutes. For WPC 85 and WPCO, the increase of curding time was observed and it was 148 and 165 minutes respectively. The hardest yogurts were obtained with 4% of WPC 85 and WPCO addition, but these yogurts characterized with too gummy structure.
yogurt, hardness, viscosity, WPC