超声波辅助碱法提取美藤果分离蛋白及其加工性质研究

Ultrasonic-assisted alkaline extraction of Plukenetia volubilis protein isolate and its processing properties

为拓宽美藤果蛋白在食品工业中的应用,采用超声波辅助碱法从脱脂美藤果饼中提取分离蛋白。在单因素试验基础上,以蛋白得率为响应值,采用响应面法对提取工艺进行优化。结果表明:超声波辅助碱法提取美藤果分离蛋白的最佳工艺条件为pH 10、超声时间16 min、超声功率220 W、超声温度43℃、液料比17∶1(mL∶g),该条件下蛋白得率为21.23%,与模型预测值21.47%相接近;美藤果分离蛋白的溶解性低于清蛋白和球蛋白,在pH 2~3和pH 10~12具有较好的溶解性;起泡性低于清蛋白,高于球蛋白,在pH 10时最大,为51.11%,起泡稳定性随pH增大而改变,在pH 10时最大,为71.52%;乳化性和乳化稳定性低于清蛋白,高于球蛋白,在pH 10时最大,分别为45.72 m 2/g和29.29 min;总巯基和游离巯基含量高于清蛋白和球蛋白,分别为8.04和3.86μmol/g。因此,超声波辅助碱法提取美藤果分离蛋白是一种绿色、高效的提取方法,美藤果分离蛋白的加工性质研究可为其应用提供理论基础。

In order to expand the application of Plukenetia volubilis protein in food industry,ultrasonic-assisted alkaline extraction was used to extract protein isolate from defatted P.volubilis cake.The protein yield was used as the evaluation index,and a response surface methodology was carried out to optimize the extraction process on the basis of a single factor experiment.Subsequently,the albumin and globulin fractions of P.volubilis were extracted,and the main processing properties were compared.The results showed that the optimum conditions of ultrasonic-assisted alkali extraction of P.volubilis protein isolate were:pH 10 for 16 min at 43℃with ultrasonic power 220 W and liquid-solid ratio 17∶1(mL∶g).Under the optimized condition,the yield was 21.23%and closed to the predicted value of 21.47%.The solubility of P.volubilis protein isolate was lower than albumin and globulin,and it had better solubility at pH 2~3 and pH 10~12.The foaming property was lower than albumin and higher than globulin,and the maximum value was 51.11%at pH 10.Moreover,the foaming stability changed with the increase of pH,and the maximum value was 71.52%at pH 10.The emulsifying property and emulsifying stability were lower than albumin and higher than globulin,and the maximum values were 45.72 m 2/g and 29.29 min at pH 10,respectively.Furthermore,the contents of total sulfhydryl and free sulfhydryl were higher than albumin and globulin,and the values were 8.04 and 3.86μmol/g,respectively.Therefore,ultrasonic-assisted alkaline extraction of P.volubilis protein isolate is a green and efficient extraction method.The study on the processing properties of the protein isolate provides a certain theoretical basis for its application.