Effects of zein modifying polar amino acids as surface stabilizers on the emulsification stability of milk cream diacylglycerol
Xiuheng Xue, Haiyong He, Cunjun Liu, Yanping Han, Jingrui He, Jiajia Zhou, Xinglei Guo, Juhua Wang, Jianbo Cheng
Abstract
It is important to improve the emulsification stability of oil-in-water emulsions by surface loading hydrophilic groups. l-Glutamic acid (Glu), l-Glutamine (Gln) and l-Arginine (Arg) were used to modify Zein-Chitosan lactate (CHL) as stabilizers to improve the emulsification stability of milk cream diacylglycerol (DAG). The mechanism of using polar amino acids to enhance the emulsification of DAG-in-water emulsion was explored. The results showed that the average droplet size of DAG emulsion was 48 μm by using Zein-CHL-Gln as surface stabilizer when the pH was 6.0, and the ratio of Gln and CHL was 1:1. Zein-CHL-Gln as surface stabilizer could improve the emulsion index by 25% compared with the control group after storage for 7 days. Hydrophobic interaction between L-Gln and zein played an important role in increasing the hydrophilic polar moiety on the emulsion surface. Zein-CHL modified with l-Glutamine was better surface stabilizer to improve the emulsification of oil-in-water emulsions.