美拉德反应改善苦荞蛋白水解物乳化性的研究

Research on the Improvement of Emulsification of Tartary Buckwheat Protein Hydrolysates by Maillard Reaction

采用碱性蛋白酶水解1 h制备的苦荞蛋白水解物(tartary buckwheat protein hydrolysates,TBPH)与3种还原糖(葡萄糖、麦芽糊精、葡聚糖)进行温和的美拉德反应,对反应温度、反应时间、反应物的浓度和pH值条件进行优化,最终确定反应条件为pH 7.0、反应浓度为10%、反应时间为3 d。3种还原糖中葡聚糖与苦荞蛋白水解物反应生成的共聚物游离氨基含量最高,具有最好的乳化活性和乳化稳定性,形成的乳状液具有最小的粒径、负电荷最多和抑制脂质氧化能力最强(P<0.05)。而葡萄糖与苦荞蛋白水解物形成的共聚物乳化效果和氧化稳定性均相对较差。试验结果也表现出还原糖的分子链越长,与苦荞蛋白水解物形成共聚物的乳化性能就越好。

In this experiment,Tartary buckwheat protein hydrolysates prepared by alkaline protease hydrolysis for 1 h were reacted with three reducing sugars(glucose,maltodextrin and dextran)in a mild maillard reaction.The reaction temperature,reaction time,concentration of reactants and pH conditions were optimized.The reaction conditions were determined to be pH 7.0,the reaction concentration was 10 %,and the reaction time was 3 d. Among the three reducing sugars,the copolymer formed by the reaction of dextran with hydrolysate of tartary buckwheat protein had the highest free amino content,the best emulsifying activity and stability,and the emulsion formed had the smallest particle size,the largest negative charge and the strongest ability to inhibit lipid oxidation(P<0.05). However,the emulsifying effect and oxidation stability of the copolymer formed by glucose and hydrolysate of tartary buckwheat protein were relatively poor. In conclusion,the longer the molecular chain of reducing sugar,the better the emulsification performance of copolymer formed with Tartary buckwheat protein hydrolysate.