高温湿热处理对大豆分离蛋白的结构及其功能特性的影响  

Effect of high temperature hydrothermal treatment on structure and functional properties of soybean protein isolate

作　　者：刘紫薇 朱明明 王凤新 赵强[1] 熊华[1] LIU Ziwei;ZHU Mingming;WANG Fengxin;ZHAO Qiang;XIONG Hua(State Key Laboratory of Food Science and Technology,Nanchang University,Nanchang 330047,China;Jiangxi Newborn Nutrition Technology Co.Ltd.,Nanchang 330052,China)

机构地区：[1]食品科学与技术国家重点实验室(南昌大学),江西南昌330047 [2]江西人之初营养科技股份有限公司,江西南昌330052

出　　处：《食品与发酵工业》2021年第15期157-164,共8页Food and Fermentation Industries

基　　金：江西省重大科技研发专项(S2018ZDYFE0040);江西省杰出青年基金项目(20192BCB23006)。

摘　　要：研究了高温湿热处理对大豆分离蛋白结构及功能特性的影响。在中性条件下,将质量分数为1%的大豆分离蛋白(soy protein isolate,SPI)溶液在70、90、120、150、170、200℃下分别处理30 min,测定其处理前后结构、溶解度、表面疏水性、乳化性及乳化稳定性的变化。红外光谱的拟合计算得出,随着处理温度升高,SPI的α-螺旋含量显著增加,β-折叠含量明显减少;荧光发射光谱的测试结果表明,湿热处理导致最大发射波长发生红移,经200℃高温湿热处理的样品,最大发射波长红移程度最大。处理温度增加到90℃,溶解性逐步提高,可能是由于产生了可溶性聚集体。处理温度为120℃时,SPI溶解度最低。处理温度继续升高至200℃,溶解度再次增加,电位绝对值降低,表明湿热处理会导致溶液的稳定性降低,易发生聚集。170、200℃高温湿热处理的样品粒径、浊度明显增大,表明SPI形成可溶性聚集体;SPI的表面疏水性和乳化性呈先增加后降低趋势,处理温度为90℃时达到最大,而乳化稳定性则逐步增加。该研究为植物蛋白尤其是大豆蛋白的热聚集改性研究提供理论基础及数据参考。In this work,the effects of high temperature and hydrothermal treatment on the structural and functional properties of soy protein isolate(SPI)were investigated.Under the neutral condition,1%(mg:mL)soy protein isolate was treated at 70,90,120,150,170,200℃for 30 min,respectively,and the changes in protein structure,solubility,surface hydrophobicity,emulsification,and emulsification stability were measured before and after treatment.The fitting of the infrared spectrum showed that the α-helix content of SPI increased,meanwhile theβ-sheet content decreased significantly.Moreover,with the treatment temperature increased,the maximum emission wavelength was redshifted and the maximum emission of the samples treated with high temperature and hydrothermal treatment at 200℃ occurred the maximum redshift.Especially,as the treatment temperature increased to 90℃,the solubility of SPI was increased gradually,which may due to the production of soluble aggregates.The solubility of SPI was the minimum when the treatment temperature was 120℃.Furthermore,with the temperature rose,the solubility was increased again until 200℃.On the other hand,the Zeta potential of SPI was decreased with the increase of treated temperature,which showed the system was unstable and easy to aggregate.Besides,the particle size and turbidity of SPI treated at 170℃and 200℃was increased obviously which indicating that SPI formed soluble aggregates.The surface hydrophobicity and emulsifying activity indexes of SPI were both increased first and then decreased,and both values reached the maximum when the treatment temperature was 90℃.While the emulsification stability increased with the increase of temperature.This research could provide a theoretical and direction for the thermal aggregation modification of plant protein,especially for soybean protein.

关 键 词：大豆分离蛋白 高温湿热处理 热聚集 二级结构 功能特性 

分 类 号：TS201.21[轻工技术与工程—食品科学]