LAUSR

Emulsifying, antioxidant and foaming properties of soy protein isolate hydrolysates (SPH) can be improved by the addition of gum arabic (GA). Here, we investigated the effects of different hydrolysis conditions on the complexation of SPH and GA, and the effects of the complex on the properties on emulsions. The results from fluorescence spectroscopy showed that the addition of GA had higher effect on bromelain and pepsin hydrolysates than trypsin hydrolysate, and therefore had higher binding constant (KA ) and number of binding sites (n). Furthermore, the addition of GA could improve protein solubility and emulsifying ability. The emulsions prepared with complexes, especially with the complex between GA and SPH obtained by pepsin hydrolysis for 3 h, had high absolute charge value, uniform particle size distribution, stable morphology and good storage stability. After storage, the emulsification index (CI) of the emulsion only increased to 23.08%; its DPPH free radical scavenging activity was 24.37±1.22% while its ABTS+ free radical scavenging activity was largely retained. During long-term storage, pepsin-treated protein (especially protein treated for 3 h) and GA can form a stable emulsion with antioxidant properties. This work provides new ideas for the development of natural and safe emulsifiers that have antioxidant properties and can be long-term stored in the food industry. This article is protected by copyright. All rights reserved.