辣椒籽分离蛋白超滤提取工艺优化及特性表征

Optimization of Ultrafiltration Extraction Process of Capsicum Seed Protein Isolate and Characterization of Its Characteristics

辣椒籽作为辣椒加工过程中的主要副产物,富含蛋白等营养物质,却未能得到有效利用。基于此,该研究以益都红辣椒籽为原料,采用超滤辅助碱溶酸沉法提取辣椒籽分离蛋白,并与传统碱溶酸沉法提取的辣椒籽分离蛋白的综合提取率、物料投入以及理化和功能特性进行对比。传统碱溶酸沉工艺提取辣椒籽分离蛋白的最佳工艺参数为料液比1∶40、提取温度40℃、提取时间180 min、浸提次数1次、碱溶pH 10。为提高蛋白提取量,减少调节pH的酸碱用量,改善分离蛋白的理化特性,采用5 kDa和10 kDa的双级膜超滤技术辅助碱溶酸沉法获得3个超滤组分,包括>10 kDa蛋白、5~10 kDa蛋白和<5 kDa蛋白,蛋白提取量较传统碱溶酸沉法提高5.28%,盐酸用量较传统碱溶酸沉法减少19.48%。相比于传统碱溶酸沉法提取的蛋白,>10 kDa蛋白的溶解度、持水力、乳化稳定性分别显著提高了9.88%、78.66%、22.69%,说明超滤辅助碱溶酸沉法能够获得理化特性更佳的辣椒籽分离蛋白,是一种具有应用前景的辣椒籽分离蛋白提取手段。

As the main by-product of Capsicum processing,Capsicum seed is rich in protein and other nutrients,but it has not been effectively used.Based on this,in this study,with Yidu red Capsicum seed as the raw material,ultrafiltration assisted alkali-solution and acid-precipitation method is used to extract Capsicum seed protein isolate,and the comprehensive extraction rate,material input,physicochemical and functional characteristics of Capsicum seed protein isolate extracted by ultrafiltration assisted alkali-solution and acid-precipitation method are compared with those extracted by traditional alkali-solution and acid-precipitation method.The optimal process parameters of Capsicum seed protein isolate by traditional alkali-solution and acid-precipitation method are solid-liquid ratio of 1∶40,extraction temperature of 40℃,extraction time of 180 min,extraction frequency of 1 time and alkali solution pH of 10.In order to increase the extraction amount of protein,reduce the dosage of acid and alkali to regulate pH,and improve the physicochemical characteristics of protein isolate,5 kDa and 10 kDa dual-stage membrane ultrafiltration technology assisted alkali-solution and acid-precipitation method is used to obtain three ultrafiltration components,including>10 kDa protein,5~10 kDa protein and<5 kDa protein.Compared with traditional alkali-solution and acid-precipitation method,the extraction amount of protein increases by 5.28%and the dosage of hydrochloric acid decreases by 19.48%.The solubility,water holding capacity and emulsification stability of>10 kDa protein significantly increase by 9.88%,78.66%,22.69%respectively compared with those extracted by traditional alkali-solution and acid-precipitation method.The results indicate that Capsicum seed protein isolate with better physicochemical characteristics could be obtained by ultrafiltration assisted alkali-solution and acid-precipitation method,which is a promising method for extracting Capsicum seed protein isolate.