乳清蛋白乳液界面性质及其物理稳定性和氧化稳定性的研究

以乳清蛋白与玉米油为原料,采用高压均质技术制备水包油型(O/W)乳液。探究乳清蛋白浓度(0.45%~3.60%)、离子强度(250 mmol/L Na Cl)对乳清蛋白乳液界面特性及其物理稳定性和氧化稳定性的影响。结果表明:随着乳清蛋白浓度的增加,乳液的粒径、乳析指数、过氧化值(POV)和丙二醛生成物(TBARS)都呈现降低的趋势,而乳液的界面蛋白浓度、电位随着蛋白浓度的增加而增加。乳液中加入250 mmol/L Na Cl能够增加乳液的粒径、乳析指数、界面蛋白含量、电位值、POV和TBARS值。上述结果表明乳液界面蛋白浓度增多,乳液的物理稳定性和氧化稳定性得到增强,而乳液中加入Na Cl后能够减弱乳液的物理稳定性和氧化稳定性。 

Study on the interfacial property,physical and oxidative stability of emulsions stabilized by whey protein

In this study,whey protein and corn oil were used to prepare oil-in-water(O/W) emulsions using high-pressure homogenization. The effects of whey protein concentration(0.45%~3.60%) and ionic strength(250 mmol/L Na Cl) on the interfacial property,physical and oxidative stability of emulsions were investigated.The results showed that increasing whey protein concentration lead to decrease in the particle size,creaming index,peroxide value(POV) and thiobarbituric acid reactive substances(TBARS),and increase in interfacial protein concentration and potential. Addition of 250 mmol/L Na Cl contributed to increase in the particle size,creaming index, interfacial protein concentration, potential, POV and TBARS values of the emulsions. These findings indicated that the physical and oxidative stability of the emulsions could be improved by increasing the interfacial protein concentration or decreasing ionic strength.