Physicochemical Properties and Stability of Conjugated Linoleic Acid Powder Oil Prepared by Whey Protein Isolate-Gum Arabic Complex

In this paper, whey protein isolate (WPI) and gum arabic (GA) intramolecular complexes with excellent emulsifying activity were used as emulsifiers to prepare stable conjugated linoleic acid (CLA) emulsions by high pressure homogenization, the emulsion particle size and stability were evaluated. Then the CLA powder were prepared by spray drying, the effects of inlet temperature and CLA concentration on the encapsulation efficiency of powdered grease were studied, the re-solubilization stability, mechanical properties and oxidation stability of CLA powder were evaluated. The optimal preparation condition was as follows:the concentration of WPI-GA intromolecular complex was 2%, the air inlet temperature was 130℃, and the CLA concentration was 15%~25%. The encapsulation efficiency was higher than 90%, the CLA powder was uniformly dispersed and its re-dissolution stability was good, the normal stress Fn reached a maximum, and the oxygen consumption rate was 0.005 μmol/(mL·min) which was significantly higher than 0.01 μmoL/(mL·min) at other concentrations. The stable conjugated linoleic acid powder oil was prepared by the emulsified activity of WPI-GA intramolecular complex, which improved its stability and expands the application of conjugated linoleic acid.