文獻名： Heat stability and rheology of high-calorie whey protein emulsion: Effects of calcium ions

作者： Qiwei Du^abc, Xuehua Ji^abc, Fei Liu^abc, Jianhua Liu^abc, Yuting Ding^abc

^aCollege of Food Science and Technology, Zhejiang University of Technology, Hangzhou, 310014, PR China

^bKey Laboratory of Marine Fishery Resources Exploitment & Utilization of Zhejiang Province, Hangzhou, 310014, PR China

^cNational R & D Branch Center for Pelagic Aquatic Products Processing (Hangzhou), Hangzhou, 310014, PR China

摘要：In this study, the effect of calcium ions (Ca²⁺) on the heat stability and rheology of high-calorie (>1.0 kcal/mL) whey protein emulsion (HCWPE) was investigated. The mass fractions of carbohydrate, lipid and protein in the emulsions were 20, 6, and 6 wt%, respectively. It was found that there was little difference in stability and rheology between emulsions (unheated) of different concentrations of Ca²⁺. However, after high-temperature sterilization (121 °C for 15 min), Ca²⁺ had a significant effect on the stability of HCWPE. The particle size and flocculation degree increased rapidly when the Ca²⁺ concentration was above 1.5 mM, and absolute ζ-potential decreased. The change of 3-week particle size and backscattering showed that the emulsion had better storage stability when the Ca²⁺ concentration was below 1.5 mM. Another interesting result was that after the high temperature sterilization, the rheological behavior of HCWPE changed from shear-thickening to shear-thinning with increase in Ca²⁺ concentration. It could be explained that free Ca²⁺ continued to bind with protein during the shearing process. The present study would provide a theoretical reference for calcium fortified functional drinks.

關鍵詞：Whey protein;Calcium ion;Heat stability;Flocculation;High-calorie emulsion