糖基化乳清分离蛋白制备共轭亚油酸水包油乳液稳定性分析

Preparation of conjugated linoleic acid oil-in-water emulsion by glycosylated whey protein isolate and its stability analysis

中文关键词:  共轭亚油酸  糖基化  超声  乳液  稳定性

英文关键词:conjugated linoleic acid  glycosylation  ultrasonic crushing method  emulsion  stability

中文摘要:

      目的 研究糖基化乳清分离蛋白(whey protein isolate, WPI)对制备的共轭亚油酸(conjugated linoleic acid, CLA)乳液的物理稳定性、抗氧化能力及脂质氧化稳定性的影响。方法 以CLA为原料, 分别采用葡萄糖(glucose, Glu)和半乳糖(galactose, Gal)对WPI进行糖基化改性, 超声破碎法制备CLA水包油乳液, 研究在不同盐离子浓度、pH和温度下CLA乳液平均粒径变化、抗氧化能力及贮藏过程中脂质氧化产物含量变化。结果 同对照组WPI-CLA相比, 经糖基化改性后制备的WPI-Glu-CLA和WPI-Gal-CLA乳液受到盐离子浓度、pH和加热温度的影响, 其平均粒径变化较小, 且分布均匀。WPI-CLA、WPI-Glu-CLA和WPI-Gal-CLA乳液对1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl, DPPH)自由基达到100%清除时的质量浓度分别为10、4、4 mg/mL, 对2,2-联氮-二(3-乙基-苯并噻唑-6-磺酸)二铵盐[2,2’-azinobis-(3-ethylbenzthiazoline-6-sulphonate), ABTS]阳离子自由基达到100%清除时的质量浓度分别为8、6、6 mg/mL。在贮藏过程中, WPI-Glu-CLA和WPI-Gal-CLA乳液的氢过氧化物及次级脂质氧化产物含量均低于对照组WPI-CLA乳液。结论 经糖基化改性修饰, 增强了CLA乳液的物理稳定性, 提高了抗氧化能力, 有效减缓了脂质氧化产物的生成。

英文摘要:

      Objective To study the effects of glycosylated whey protein isolate (WPI) on the physical stability, antioxidant capacity and lipid oxidation stability of conjugated linoleic acid (CLA) emulsion. Methods With CLA as raw material, glucose (Glu) and galactose (Gal) were used to modify WPI, and CLA oil-in-water emulsion was prepared by ultrasonication. The average particle size change, antioxidant capacity and lipid oxidation product content of CLA emulsion under different salt ion concentration, pH and temperature were studied. Results Compared with the control group WPI-CLA, the WPI-Glu-CLA and WPI-Gal-CLA emulsions prepared by glycosylation modification were affected by salt ion concentration, pH and heating temperature. The average particle size changes were small and evenly distributed. The mass concentrations of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging of WPI-CLA, WPI-Glu-CLA and WPI-Gal-CLA emulsions were 10, 4 and 4 mg/mL, respectively. The mass concentrations of 2,2’-azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS) radical scavenging were 8, 6 and 6 mg/mL, respectively. During storage, the content of hydroperoxides and secondary lipid oxidation products in WPI-Glu-CLA and WPI-Gal-CLA emulsions were lower than those in the control group WPI-CLA emulsion. Conclusion After glycosylation modification, the physical stability of CLA emulsion is enhanced, the antioxidant capacity is improved, and the formation of lipid oxidation products is effectively slowed down.