乳清蛋白-乳糖接枝反应产物的抗氧化活性的评价

Evaluation on antioxidant activity of whey protein- lactose congjugate production

目的评价乳清蛋-乳糖接枝反应产物的抗氧化活性。方法热处理脱盐乳清粉溶液制备乳清蛋白-乳糖接枝反应产物,光谱扫描检测褐变程度及美拉德产物的形成,采用ABTS(2,2'-azinobis(3-ethylbenzthiazoline-6-sulfonic acid)法和ORAC(Oxygen Radical Absorption Capacity)法评价抗氧化活性。结果脱盐乳清粉经热处理后获得褐色产物;乳清蛋白-乳糖接枝反应产物的A280、A325、A405和A420分别为1.722、0.65、0.19和0.161,ABTS阳离子自由基的清除活性IC50为(2.81±0.01)mg/ml,相对ORAC值为(43.03±8.95)μmole TE/g。结论脱盐乳清粉溶液经热处理后发生美拉德反应,产生褐色的乳清蛋白-乳糖接枝反应产物,该产物具有较强的抗氧化活性。

Objective To investigate antioxidant activity of whey protein- lactose congjugateisolated from demineralized whey powder D70. Methods Whey protein- lactose congjugateproductionwas prepared by heating treatment. Brown intensity and Maillard reaction products were determined by spectral scanning,ABTS and ORAC method was used for evaluation of antioxidant activity of the products. Results The browning product was obtained. The absorbency of whey protein- lactose congjugate at 280 nm,325 nm,405 nm and 420 nm were1. 722,0. 65,0. 19 and 0. 161 respectively. ABTS ＋ scavenging activity IC50 was 2. 81 0. 01 mg / ml,and oxygen radical absorption capacitywas 43. 03 8. 95μmole TE / g. Conclusions Whey protein- lactose congjugate with brown color was obtained from demineralized whey powder solution during Maillard reaction by heating treatment.The product has higher antioxidant activity.