聚合乳清浓缩蛋白对发酵乳饮料稳定性的影响

Effect of Polymerized Whey Protein Concentrate on the Stability of Fermented Milk Beverage

以发酵乳饮料为研究对象,探讨聚合乳清浓缩蛋白的添加量对发酵乳饮料稳定性的影响。考察了聚合乳清浓缩蛋白替代总蛋白对发酵乳饮料的离心沉降率、吸光比、粒径、黏度、表面疏水性、游离巯基的影响。研究结果表明,添加聚合乳清浓缩蛋白的发酵乳饮料离心沉降率显著低于未添加聚合乳清浓缩蛋白的发酵乳饮料(P<0.05);随着聚合乳清浓缩蛋白替代总蛋白比例的增加,发酵乳饮料的吸光比先增加后略有减小;而发酵乳饮料的黏度逐渐增大;发酵乳饮料的粒径先减小后略有增大,且聚合乳清浓缩蛋白替代总蛋白比例为30%时体系粒径最小;发酵乳饮料的疏水性和游离巯基逐渐增大,聚合乳清浓缩蛋白替代总蛋白比例为10%~40%的发酵乳饮料的游离巯基显著大于空白(P<0.05)。研究结果表明,适当添加聚合乳清浓缩蛋白有利于发酵乳饮料的稳定。

The objective of this study was to determine the effect of different amounts of polymerized whey protein concentrate on the stability of fermented milk beverage. The effects of the addition of polymerized whey protein concentrate on the centrifugal sedimentation rate, light absorption ratio, particle size, viscosity, surface hydrophobicity, free thiol groups of fermented milk beverage were investigated. The results showed that the centrifugal sedimentation rate of fermented milk beverage with polymerized whey protein concentrate was significantly lower than that of fermented milk beverage without polymerized whey protein concentrate（P〈0.05）. With the increase of the polymerized whey protein concentrate, light absorbing of fermented milk drink down slightly after the first increase, viscosity of fermented milk drinkincreased gradually, the particle size decreased slightly and then increased slightly, and the addition amount of the polymerized whey protein concentrate was 30% when the size of the system was smallest, the surface hydrophobicity and free thiol groups ofsystem increased gradually, and the free thiol groups of the fermented milk drink with 10%-40% polymerized whey protein concentrate was significantly higher than that of 0%（P〈0.05）. These results indicated that adding appropriate polymerized whey protein concentrate is conducive to the stability of fermented milk beverage.