选择6种不同的糖基配体,通过湿热糖基化反应,研究乳清蛋白不同糖基化复合物在不同pH值下的反应特性及抗氧化特性。结果表明:在pH值3～9的条件下,6种乳清蛋白糖基化复合物与乳清蛋白420nm和294nm处的吸光值差异显著(P<0.05);且6种乳清蛋白糖基化复合物的游离氧基酸含量均显著降低(P<0.05)。除了乳清蛋白-蔗糖复合物外,其他5种乳清蛋白糖基化复合物的还原能力、DPPH自由基清除能、·OH自由基清除能力和抗脂质过氧化能力随pH值的升高都有所提高。乳清蛋白-木糖复合物的抗氧化能力提高最大,而且在pH值7～9的反应条件下,具有比V_C更高的还原能力。

Characteristics and antioxidant property of the conjugates of whey protein and six types of saccharides under various conditions of pH were studied by means of the moist-heating glycosylated reaction.It was shown that the absorbance at 420nm and 294nm of the six glycosylated proteins were significantly different after glycosylated reaction under the pH3～9(P < 0.05 ).Meanwhile,In addition to conjugate of WPI-Scruose,the free amino group contents of other six glycosylated conjugates decreased significantly(P < 0.05 ).And the reducing power,DPPH radical scavenging activity,hydroxyl radicals scavenging and inhibition of lipid peroxidation were greatly improved with the increasing of pH,except for WPI-Scruose conjugates.The WPI-Xylose conjugate had the best antioxidant property among all the conjugates,and had stronger reducing power than Vc under the condition of pH 7～9.