超声辅助酶法水解苏姜猪油脂工艺的优化

Optimization on Ultrasound-Assisted Enzymatic Hydrolysis of Sujiang Pork Lard

采用响应面实验设计方法研究超声辅助酶法水解苏姜猪油脂的最佳工艺,并测定酶解对油脂性质的影响。以熔点、水解率为指标,通过单因素实验确定了加酶量、pH值、超声功率、反应温度和反应时间等单因素范围。采用Box-Behnken Design建立回归模型,分析pH值(7.5~8.5)、反应时间(4~8 h)、超声功率(160~200 W)对苏姜猪油脂熔点和水解率的影响,优选出最佳的酶解工艺条件。结果显示,分别以熔点和水解率作为响应值,采用Box-Behnken Design建立的2个回归模型的R^(2)分别为0.9956、0.9914,回归模型拟合度良好,优选得到超声辅助酶法水解苏姜猪油脂的最佳工艺参数为:加酶量4%、反应温度55℃、pH7.8、反应时间6.6 h、超声频率10 kHz、超声功率170 W;其熔点比干法低,水解率比干法高。在此条件下,熔点为16.53±0.12,低于干法30.38±0.23;水解率为89.24±0.36,高于干法79.40±0.45;酸价为0.21±0.01,低于干法0.35±0.01;碘值为67.34±0.71,高于干法50.17±0.83;皂化值为276.32±5.24,高于干法200.50±3.18。通过超声辅助酶法水解,改善了苏姜猪油脂的性质,提高了应用价值。

In this paper, the optimum technology of ultrasound-assisted enzymatic hydrolysis of Sujiang pork lard was investigated by response surface methodology. On the basis of single factor, enzyme addition, pH, ultrasonic power, reaction temperature and reaction time were determined with the melting point and hydrolysis rate as indexes. The regression models were established by box behnken design and used to analyze the effects of pH(7.5~8.5), reaction time(4~8 h), ultrasonic power(160~200 W)on the properties of Sujiang pork lard, and the optimum technology parameters were selected. The results showed that the melting point and hydrolysis rate as response values, R^(2) of the two regression models were 0.9956 and 0.9914 respectively, the fitting degree of the regression model was good. The optimal technological parameters for ultrasound-assisted enzymatic hydrolysis of Sujiang pork lard were obtained as follows: enzyme dosage 4%, reaction temperature 55 ℃ and pH 7.8, reaction time 6.6 h, ultrasonic frequency 10 kHz, ultrasound power 170 W. Under these conditions, the melting point 16.53±0.12 was lower than that of the dry method 30.38±0.23, the hydrolysis rate 89.24±0.36 was higher than that of the dry method 79.40±0.45, the acid value 0.21±0.01 was lower than that of the dry method 0.35±0.01, the iodine value 67.34±0.71 was higher than that of the dry method 50.17±0.83, the saponification value 276.32±5.24was higher than that of the dry method 200.50±3.18. Through ultrasonic assisted enzymatic hydrolysis, the properties of Sujiang pork lard were improved, which had highly potential application.