反胶束提取扁桃仁蛋白工艺优化及理化特性比较

Process Optimization of Almond Protein Extraction by Reverse Micelles and Comparison of Its Physicochemical Properties

以AOT为表面活性剂构建的反胶束体系对扁桃仁蛋白的提取。对前、后提取分别进行单因素试验并阐述其影响作用,在此基础上对前提取进行响应面优化试验。最终前提取的最佳工艺参数分别为料液质量比1:15、AOT质量浓度0.11 g/mL、温度41℃、pH值为7.0和后提取的KCl浓度0.5 mol/L、温度45℃、新水相pH值为8.0。该条件下扁桃仁蛋白的前提取率为67.37%,后提取率为66.50%。其理化特性的试验结果显示乳化性和起泡性在20~100℃范围内先升高后降低,在pH值3.0~9.0范围内缓慢下降后持续升高,在40℃下和pH值为9.0时的乳化性和起泡性较好,分别为乳化性:48.93 m^(2)/g、60.22 m^(2)/g;起泡性:75.70%、88.05%。这结果与温度对表面疏水性的影响有较大差异(80℃时蛋白表面疏水性最好)。抗氧化活性试验结果显示扁桃仁蛋白对ABTS+.的清除能力强于DPPH.。其他如溶解性(74.84%)、持水性(4.34 g/g)和持油性(5.77 g/g)等特性均较理想。综上所述,反胶束法用于扁桃仁蛋白的提取有助于得到高质量的扁桃仁蛋白,为反胶束法应用于扁桃仁蛋白的提取提供科学依据。

Almond protein was extracted by a reverse micelle system constructed using AOT as the surfactant.Single-factor experiments were conducted on the first and second extraction processes to study their effects.Based on this,response surface optimization experiments were performed on the first extraction process.The optimal parameters for the first extraction are as follows:a solid to liquid mass ratio of 1:15,an AOT mass concentration of 0.11 g/mL,a temperature level of 41℃,and a pH value of 7.0.For the second extraction,the optimal conditions are as follows:a KCl concentration of 0.5 mol/L,a temperature level of 45℃,and a pH value of 8.0 for the new aqueous phase.Under these conditions,the almond protein extraction rate of the first and second extraction processes reaches 67.37%and 66.50%,respectively.The physical and chemical properties indicate that emulsifiability and foamability initially increase and then decrease as the temperature rises within the range of 20 to 100℃,while they decrease slowly and then increase continuously as the pH value increases from 3.0 to 9.0.The emulsifiability and foamability of the extracted almond protein are optimal at 40℃and pH 9.0.More specifically,the emulsifiability reaches 48.93 m2/g and 60.22 m2/g,respectively,whereas the foamability reaches 75.70%and 88.05%,respectively.These results differ from the effects of temperature on surface hydrophobicity,as the highest surface hydrophobicity is observed at 80℃.Antioxidant activity analysis revealed that almond protein exhibits stronger scavenging ability against ABTS compared to DPPH.Other properties,including solubility(74.84%),water holding capacity(4.34 g/g),and oil holding capacity(5.77 g/g),are favorable.In conclusion,applying the reverse micelle method for almond protein extraction is beneficial in obtaining high-quality almond protein,and the above finding provide a scientific basis for the application of this method in almond protein extraction.