| 摘要: |
| 【目的】分析高压均质处理对大豆蛋白-乳清蛋白混合体系性质的影响，为动植物混合蛋白的加工应用提供参考。【方法】制备400 mg/L的大豆分离蛋白（SPI）、乳清分离蛋白（WPI）和大豆蛋白 乳清蛋白混合蛋白体系(SPI-WPI)，对其分别进行0，30，60，90，120，150 MPa的均质压力处理，观测高压均质处理前后的乳化活性、乳化稳定性、粒径、电位、表面疏水性、浊度以及乳液微观结构，研究高压均质处理对SPI WPI混合体系性质的影响。【结果】与SPI和WPI相比，随均质压力增大，SPI-WPI混合体系的乳化活性和乳化稳定性均明显提高，在压力为150 MPa时其乳化活性和乳化稳定性均达到峰值，分别为80.6 m2/g和16.1 min，较高压均质处理前（59.264 m2/g和14.01 min）分别提高了36.06%和14.85%。经高压均质处理后，SPI-WPI混合体系的粒径分布由双峰转为单峰，与未处理样品相比平均粒径显著降低（P＜0.05）。SPI-WPI混合体系的ZETA电位绝对值随均质压力的升高呈先增大后减小的趋势，于压力为120 MPa时达到最高，为23.66 mV，此时混合体系稳定性最好；随着均质压力的升高，SPI、WPI、SPI-WPI混合体系的浊度均呈下降趋势。经高压均质处理后，SPI-WPI混合体系的表面疏水性明显增强，混合体系中蛋白分子伸展，内部的疏水基团暴露，体系相互排斥作用增强；乳液的微观结构由孔洞较大且排列不规则转为均一、稳定结构。【结论】高压均质处理有利于SPI WPI混合体系中两种蛋白相互作用，从而改善混合体系的功能性质。 |
| 关键词: 大豆分离蛋白 乳清分离蛋白 混合体系 高压均质 乳化特性 |
| DOI： |
| 分类号: |
| 基金项目:吉林省科技发展计划项目(20180201045NY) |
|
| Effect of high pressure homogenization on properties of soy protein-whey protein mixed system |
|
LIU Peng,XIAN Yuwangqiao,SHAO Xinru,et al
|
| Abstract: |
| 【Objective】In this paper,the effect of high pressure homogenization on properties of soybean-whey protein mixed system was studied to provide basis for the processing and application of mixed protein of animals and plants.【Method】The soy protein isolate (SPI),whey protein isolate (WPI),and soy-whey protein mixed protein system (SPI-WPI) at concentration of 400 mg/L was prepared,and was subjected to 0,30,60,90,120,150 MPa homogeneous pressure treatments.The emulsification activity,emulsification stability,particle size,ZETA potential,surface hydrophobicity,turbidity,and emulsion microstructure were analyzed before and after high pressure homogenization.The effects of high pressure homogenization on properties of the SPI-WPI mixed system were then studied.【Result】 Compared with SPI and WPI,high pressure homogenization significantly improved the emulsification and emulsifying activity of the SPI-WPI mixed system.When the pressure was 150 MPa,they reached the peaks of 80.6 m2/g and 16.1 min,which were 36.06% and 14.85% higher than those without treatment（59.264 m2/g and 14.01 min）,respectively.After high pressure homogenization treatment,the particle size distribution of the system changed from double peak to single peak.The volume average particle size of the treated mixed system was significantly lower than that of the untreated sample (P<0.05).The absolute value of ZETA potential increased first and then decreased with peak value of 23.66 mV and the best stability at 120 MPa.With the increase of homogenization pressure,the turbidity of SPI,WPI,and SPI-WPI mixed system decreased.The surface hydrophobicity was significantly improved by high pressure homogenization treatment.Simultaneously,the protein molecules of the mixed system unfolded with the internal hydrophobic groups exposed and the mutual repulsion of the system enhanced.The microstructure of the emulsion was transformed from a large pore with an irregular arrangement to a uniform and stable structure.【Conclusion】High pressure homogenization treatment was beneficial to the interaction of SPI-WPI mixed system and improved the functional properties of the mixed system. |
| Key words: soy protein isolate whey protein isolate mixed system high-pressure homogenization emulsifying properties |
