胃蛋白酶水解大米蛋白的研究

Pepsin Hydrolysis of Rice Protein Powder

采用胃蛋白酶对大米蛋白进行水解以改善其功能性质。结果表明,酶添加量7U/g(以蛋白质干基计)、pH1.5、时间5h、温度30℃时,胃蛋白酶对大米蛋白溶解性有较好的改善作用。水解后大米蛋白的乳化稳定性与乳化性分别为33.28min、0.456,高于大豆蛋白和鸡蛋清蛋白;起泡性和起泡稳定性比未经过任何处理的大米蛋白分别提高了25.0%、82.4%;持水性和持油性为2.80、3.30g/g,是未经处理的大米蛋白的2.09、2.92倍。

Rice protein powder was hydrolyzed with pepsin to improve its functional properties. The effects of pepsin amount, reaction time and temperature and pH on soluble protein concentration in hydrolyzed rice protein powder were studied. Results showed that the optimal hydrolysis reaction for 5 h at pH 1.5, 30 ℃ and an enzyme dosage of 7 U/g （calculated on the basis of dry protein weight） resulted in an optimal improvement in the solubility of rice protein powder and the resulting hydrolysate exhibited 0.456 min emulsifying capacity and 33.28 min emulsion stability, which were both higher than those of soybean protein powder or egg white protein powder, 25.0% and 82.4% higher foaming capacity and foam stability than unhydrolyzed rice protein powder, respectively, and 2.80 g/g water holding capacity and 3.30 g/g oil holding capacity, with 2.09-and 2.92-fold enhancement in comparison with unhydrolyzed rice protein powder, respectively.