火麻仁蛋白的反胶束法提取工艺、理化性质及消化率研究

Optimization of extraction process of hemp seed protein by reverse micelle method and study on its physicochemical properties and digestibility

[目的]利用反胶束法提取火麻仁蛋白,进行工艺优化并分析所得蛋白的理化性质。[方法]对前萃取液2-乙基己基琥珀酸酯磺酸钠(AOT)质量浓度、加水量、缓冲液pH值、KCl浓度、料液比、前萃取温度、前萃取时间与后萃取液pH值、KCl浓度、后萃取时间、后萃取温度等影响蛋白提取率的关键因素进行优化,考察所得蛋白的溶解性、持水性、持油性与消化特性。[结果]反胶束最佳前萃取条件为AOT质量浓度0.0904 g/mL、缓冲液pH值6.54、加水量0.1058 mL/mL、KCl浓度0.05 mol/L、料液比1∶30(g/mL)、前萃取时间60 min、前萃取温度50℃,前萃取率达71.38%;最佳后萃取条件为pH值7.5、KCl浓度1.5 mol/L、后萃取时间45 min、后萃取温度27℃,后萃取率达80.59%,总萃取率为57.53%。经透析、冷冻干燥所得蛋白为白色、蓬松粉末,纯度达98.12%,其溶解性随pH值变化显著,持水性为0.71 g/g,持油性为3.57 g/g,消化率为93.83%。[结论]火麻仁蛋白可用反胶束法提取,较好的持油性、高消化率等特性使火麻仁蛋白在食品应用中具有独特的优势。

[Objective]The process was optimized and the physicochemical properties of the obtained hemp seed protein,extracted by using reverse micelle method,were analyzed.[Methods]The key factors affecting the extraction rate of protein,such as Aerosol-OT(AOT)mass concentration,water addition,buffer pH,KCl solution concentration,solid-liquid ratio,extraction temperature and time of preextraction process,and pH,KCl concentration,extraction time and temperature of post-extraction progress,were analyzed by single factor analysis and response surface optimization.The solubility,water holding capacity,oil holding capacity and digestion characteristics of the obtained protein were investigated.[Results]The optimal process conditions for the reverse micelle pre-extraction were obtained as follows:AOT mass concentration 0.0904 g/mL,buffer pH 6.54,water addition 0.1058 mL/mL,KCl concentration 0.05 mol/L,solid-liquid ratio 1∶30(g/mL),extraced for 60 min at 50℃.The pre-extraction rate was 71.38%.The optimal process conditions for the reverse micelle post-extraction were obtained as follows:pH 7.5,KCl concentration 1.5 mol/L,post-extraction time 45 min,temperature 27℃.The postextraction rate was 80.59%,and the total extraction rate was 57.53%.The white and fluffy protein powder with purity of 98.12%was obtained by dialysis and freeze-drying.Its solubility changed significantly with pH values.The water holding capacity was 0.71 g/g,the oil holding capacity was 3.57 g/g,and the digestibility was 93.83%.[Conclusion]Reverse micelle method can be used to extract hemp seed protein.The characteristics of excellent oil holding capacity and high digestibility make hemp seed protein have unique advantages in food application.