酶法替代碱法提取琼脂生产技术开发

Development of Agar Extraction with Enzyme-replacing-alkali Process

为了减少琼脂提取过程中的碱用量,开发琼脂的绿色清洁生产工艺,以凝胶强度为考察指标,通过单因素试验对酶法替代碱法提取琼脂的工艺进行了优化。结果表明,酶法辅助琼脂提取工艺最优条件为:碱质量分数3%,处理时间2.5 h,处理温度45℃,pH值7.0,加酶量4 U/mL;复合酶法工艺最佳提取条件为:酶处理温度50℃,处理时间2 h,纤维素酶单位活力14 U/mL,琼脂硫酸酯酶单位活力26.6 U/mL,料水比(m/V)为1∶18。在此基础上,分别开展了酶法辅助和复合酶法2种工艺的小试优化结果的验证与200 L放大试验。其中,小试工艺验证结果表明,酶法辅助和复合酶法2种提取工艺下,琼脂的凝胶强度分别为831.9 g/cm^2和377.2 g/cm^2,得率分别为18.9%和18.3%;200 L中试放大试验结果显示,2种工艺琼脂的凝胶强度分别为1001.3 g/cm^2和369.6 g/cm^2。说明,2种工艺均具有良好的稳定性和重复性。

In order to reduce alkali consumption in the process of agar extraction,two eco-friendly methods for agar extraction,named enzyme-assisted extraction method and composite enzyme extraction method were developed.The extraction conditions were optimized for improvenment of gel strength by single-factor experiment.The optimized conditions for enzyme-assisted process were as follows:3%alkali treatment for2.5h,4U/m L enzyme treatment for2.5h at45°C and pH7.0.The optimized conditions for composite enzyme was that14U/m L cellulase,26.6U/m L agar sulfatase and mass/water ratio of1:18were used for agar extraction at50°C for2h.The optimal parameters of enzyme-assisted and composite enzyme extraction processes were carried out at the200L scale in order to validate the feasible of lab procedures.The results showed that the gel strength of agar extracted by enzyme-assisted extraction and composite enzyme extraction was831.9g/cm2and377.2g/cm2,respectively.The yields were18.9%and18.3%,respectively.The results displayed that the gel strengths were1001.3g/cm2and369.6g/cm2,respectively,which revealed that both processes have good stability and reproducibility.