摘要
采用大豆分离蛋白(Soy Protein Isolate,SPI)、大豆球蛋白(11S)和β-伴大豆球蛋白(7S)为原料,进行酯化改性,研究反应时间、盐酸浓度以及蛋白质与甲醇的物料比对蛋白质酯化率的影响。根据酯化率确定3种酯化大豆蛋白(MSPI、M11S、M7S)的制备条件,并测定酯化大豆蛋白的红外光谱、Zeta-电位和抑菌性。结果表明:当反应时间控制在10 h,盐酸浓度为1.5 mol·L^(-1),蛋白质与甲醇物料比为5%(W/V)时,MSPI、M11S的酯化效果好,产率高;当反应时间、盐酸浓度以及蛋白质与甲醇物料比分别为8 h、1.5 mol·L^(-1)和5%(W/V)时,M7S的酯化效果好,产率高。MSPI、M11S、M7S的蛋白质等电点(pI)分别为pH=10.3、pH=9.0和pH=10.4。在pH=5.0的条件下,MSPI、M11S、M7S对革兰氏阴性菌和革兰氏阳性菌具有优良的抑菌性,抑菌最小浓度分别为0.1 mg·mL^(-1)、1.0 mg·mL^(-1)、0.1 mg·mL^(-1)。本实验成功制备了3种酯化大豆蛋白,并研究了酯化大豆蛋白的抑菌效果,为大豆蛋白应用在偏酸性食品领域提供了理论依据。
As raw materials, soybean protein isolate(SPI), glycinin(11S) and β-conglycinin(7S) were used for the modification on esterification. The effects of reaction time, hydrochloric acid concentration and the ratio of protein to methanol on protein esterification rate were studied. According to the esterification rate, the preparation conditions of the three kinds of esterified soybean proteins(MSPI, M11S, M7S) were determined, and the infrared spectrum, Zeta-potential and antibacterial activity of the esterified soybean proteins were measured. The results showed that the esterification effect of MSPI and M11S was good and the yield was high while the reaction time was 10 h, the hydrochloric acid concentration was 1.5 mol·L^(-1)and the ratio of protein to methanol was 5%(W/V). And when the reaction time, the hydrochloric acid concentration and the ratio of protein to methanol were 8 h, 1.5 mol·L^(-1)and 5%(W/V), the esterification effect of M7S was good and the yield was high. The isoelectric point(pI) of protein of MSPI, M11S and M7S were pH=10.3, pH=9.0 and pH=10.4. At pH=5.0, MSPI, M11S and M7S expressed prominent antibacterial activity against Gram-negative bacteria and Gram-positive bacteria. The minimal antibacterial concentrations were 0.1 mg·m L^(-1), 1.0 mg·m L^(-1)and 0.1 mg·m L^(-1). In this experiment, three kinds of esterified soybean proteins were successfully prepared, and the antibacterial effect of esterified soybean protein was studied. This research provided theoretical support for the application of soybean protein in acidic food field.
作者
陈菲
武若飞
萨日娜
姚英杰
许晶
CHEN Fei;WU Ruofei;SA Rina;YAO Yingjie;XU Jing(College of Art and Science,Northeast Agricultural University,Harbin 150030,China)
出处
《现代食品》
2022年第6期75-82,共8页
Modern Food
基金
东北农业大学SIPT项目(202110224367)。
关键词
大豆蛋白
酯化改性
抑菌性
soybean protein
esterification
antibacterial activity
