响应面法优化β-半乳糖苷酶法制备低聚半乳糖工艺

本文以乳糖为起始原料，在单因素实验的基础上，结合响应面分析法考察加酶量、反应温度、反应时间、反应pH等因素对低聚半乳糖总产率和低聚半乳四糖产率的影响，优化β-半乳糖苷酶法制备低聚半乳糖工艺。结果表明，β-半乳糖苷酶法制备低聚半乳糖的最佳工艺参数为起始乳糖浓度300 g/L、加酶量8.25 U/g乳糖、反应温度49 ℃、反应时间16 h、反应pH5.6。在此条件下，低聚半乳糖总产率为14.61%，低聚半乳四糖产率为3.31%。该方法针对性提高高聚合度低聚半乳糖的产率，可为低聚半乳糖的功能性应用及特医食品的研发提供参考。

Optimization of Preparation of Galactooligosaccharides by β-Galactosidase Using Response Surface Methodology

In this study, lactose was used as raw material, on the basis of single factor experiment and combined with response surface methodology, enzyme addition, reaction temperature, reaction time, reaction pH and other factors were utilized to investigate the influence of the galactooligosaccharides total yield and the galactotetraose yield. The process of enzymatic preparation of galactooligosaccharides by β-galactosidase was optimized. The results showed that the optimum process parameters for the enzymatic preparation of galactooligosaccharides were as follows: The initial lactose concentration was 300 g/L, the amount of enzyme added was 8.25 U/g lactose, the reaction temperature was 49 ℃, the reaction time was 16 h, and the reaction pH was 5.6. Under these conditions, the galactooligosaccharides total yield was 14.61% and the galactotetraose yield was 3.31%. The method selectively improved the yield of galactooligosaccharides with high degree of polymerization, which would provide a certain theoretical reference for the functional application of galactooligosaccharides and the further study and development of special medical food.