花生蛋白的高静压联合酶法改性及其性质Modification of peanut protein by high hydrostatic pressure combined with enzymatic method and its properties

为促进花生蛋白的深加工和更广泛的应用，采用高静压联合碱性蛋白酶酶法改性花生蛋白。通过单因素试验考察了静压力、pH、酶添加量、酶解时间和酶解温度对花生蛋白溶解度的影响，在此基础上，采用正交试验优化花生蛋白联合改性工艺条件，并测定了联合改性花生蛋白的起泡性和泡沫稳定性、巯基和二硫键含量以及总还原能力。结果表明：花生蛋白联合改性最佳工艺条件为静压力300 MPa、1 g/100 mL碱性蛋白酶（20万U/g）添加量3.0 mL（100 mL质量分数5%的花生蛋白溶液）、酶解时间60 min、pH 10、酶解温度50 ℃，在此条件下联合改性花生蛋白溶解度为（82.87±0.51）%；联合改性花生蛋白的起泡性、泡沫稳定性、巯基含量、总还原能力显著提高，二硫键含量显著下降。综上，高静压联合酶法改性改善了花生蛋白的理化性质及功能特性，有利于其深加工及更广泛的应用。In order to promote the deep processing and broader application of peanut protein, peanut protein was modified by high hydrostatic pressure combined with alkaline protease hydrolysis. The effects of hydrostatic pressure, pH, enzyme addition amount, enzymatic time and enzymatic temperature on the solubility of peanut protein were investigated by single factor experiment, then orthogonal experiment was used to optimize the modification process of peanut protein. The foaming property and foam stability, sulfhydryl and disulfide bond contents, and total reducing capacity of the co-modified peanut protein were determined. The results showed that the optimal co-modification conditions for peanut protein were hydrostatic pressure 300 MPa, 1 g/100 mL alkaline protease(200 000 U/g) addition amount 3.0 mL (based on 100 mL peanut protein solution with mass fraction of 5%), pH 10, enzymatic temperature 50 ℃, and enzymatic time 60 min, and the protein solubility was (82.87±0.51)% under these conditions. The foaming property and foam stability, sulfhydryl group content, and total reducing capacity of co-modified peanut protein improved, while the disulfide bond content decreased. In conclusion, the combination of high hydrostatic pressure and enzymatic method can improve the physicochemical properties and functional properties of peanut protein, which facilitates the deep processing and broader application of peanut protein.