摘要
以高速离心得到的乳清蛋白为原料,并配制成不同pH的溶液,进一步对体系表观黏度、Zeta电势、表面张力、平均粒径和稳定性的变化规律进行了研究。结果表明:随着pH的降低,样品的Zeta电势值(绝对值)逐渐降低,表明乳清蛋白分子表面所带的电荷逐渐减小,分子间的静电斥力作用相应逐渐降低;表观黏度值随pH的降低先增大后降低,在pH5.4附近时有最大值;而表面张力和平均粒径分别是先降低后增大,且在pH5.4-7.0变化不明显,在pH6.6时分别有最小值55.04mN/m2和20.286nm。稳定性扫描图的结果显示,乳清蛋白溶液在pH5.8-7.0内稳定性较好,且在pH6.6时稳定性最好。因而在中性乳制品的加工过程中应该以pH6.6为最佳值进行配方设计和加工制作。
In this paper, whey protein received by high speed centrifugation was used as material and made into solutions with different pH values. The change law of Viscosity, Zeta potential, surface tension, average particle size and stability were measured. Results showed that Zeta potential value （ absolute value） decreased with the fall of pH, which indicates that electric charge on the surface of whey protein surface and static decreased gradually with the fall of pH. Viscosity first increased and then decreased with a maximum value around pH 5.4. While surface tension and average particle size decreased initially and then increased and had no obvious change during pH 5.4 -7.0. Surface tension and average particle size reached the least value of 55.04mN/m^2 and 20. 286nm at pH 6.6. The scanning graphs of stability indicated that whey protein solutions with the pH between 5.8 and 6.6 were more stable and had the best stability at pH6.6. PH6.6 should be the optimum value for formula design and manufacturing during the processing of neutral dairy products.
出处
《食品与发酵工业》
CAS
CSCD
北大核心
2009年第8期156-159,共4页
Food and Fermentation Industries
基金
中国博士后科学基金资助项目(20070411100)
山东省自然科学基金资助项目(2007ZRB02217)
