关键词: 变性程度；清酪蛋白比例；稀奶油；稳定性；搅打特性

Abstract: In this study, the effects of the denaturation degree of whey protein (WP) and whey protein/casein (WP/CN, m/m) ratio in milk powder on the emulsion stability and whipping properties of recombined cream were investigated. The results showed that the cream prepared from milk power with 60% of WP denaturation had good emulsion stability, and the stability of the system decreased with increase in denaturation degree. An increase in the degree of WP denaturation shortened the whipping time and reduced the leakage rate of whey. The emulsion stability at a WP/CN ratio of 1:4 first increased and then decreased to a level higher than the initial one with increasing proportion of WP. In addition, the whipping time of the cream was shortened, and whey leakage was reduced, while foaming rate declined and bubble collapse rate increased. In summary, the cream prepared from milk power with 60% of WP denaturation showed good emulsion stability and whipping properties; it had the best stability at a WP/CN ratio of 2:4 and better foaming capacity and foam stability at a WP/CN ratio of 1:4. Therefore, WP/CN ratio can be adjusted according to the practical needs to improve the functional characteristics of cream products.

Key words: degree of denaturation; ratio of whey protein to casein; cream; emulsion stability; whipping properties