响应面法优化果胶酶澄清酸枣汁工艺的研究

Optimization of Process Conditions of Wild Jujube Juice Clarification by Pectinase Using Response Surface Methodology

优化果胶酶澄清酸枣汁的工艺。试验以酸枣汁中果胶含量为响应值,根据Box-Benhnken中心组合设计原理,选取酶解p H、酶解温度、果胶酶用量以及酶解时间进行四因素三水平响应面试验,优化果胶酶澄清酸枣汁工艺。试验建立了回归方程,即果胶含量Y=166.58-1.23A+0.11B+0.17C-0.63D+8.57AB-4.1AC-2.18AD+0.93BC-0.57BD+0.92CD+14.65A^2+39.16B^2+40.00C^2+42.06D^2。通过响应面分析得到了果胶酶的最佳酶解条件:酶解pH 4.5、酶解温度55℃、果胶酶用量0.31%、酶解时间1.5 h,在此条件下,酸枣汁中果胶含量降至170.273 mg/L,降解率为65.54%,与模型预测值之间具有较好的拟合性。果胶酶澄清酸枣汁效果明显,本研究所得为酸枣汁澄清工艺提供了良好的技术参数。

The study focused on the optimization of process conditions of wild jujube juice clarification by pectinase. The contents of pectin was used as response value, pH, temperature,enzyme amount, enzymolysis time were choosed as variables.According to the principle of Box-Behnken experimental design, the three vari-ables at four selected levels were optimized by response surface methodology. A mathematical regression model was established,Y=166.58-1.23A＋0.11B＋0.17C-0.63D＋8.57AB-4.1AC-2.18AD＋0.93BC-0.57BD＋0.92CD＋14.65A2＋39.16B2＋40.00C2＋42.06D2. Results showed that the optimum process conditions were found to be enzy-molysied at 55℃with a total enzyme dosage of 0.31%and 1.5 h under the hydrolysis pH 4.5. under this condi-tion, contents of pectin decreased to 170.273 mg/L,which was well matched with the predicted value, the degradation rates of pectin were 65.54 %.Pectinase had an obvious effect on the clarification of wild jujube juice, this study provided good process parameters for the clarification of wild jujube juice.