酶法脱酯从柚皮中制取低甲氧基果胶的工艺研究

Extraction of Lowmethoxyl Pectin from Grapefuit Peel by Activation Pectin Esterase

以新鲜柚皮为原料,添加碳酸钠激活内源果胶酯酶制备低甲氧基果胶。以果胶甲氧基含量和得率为指标,通过正交实验优化酶法脱酯及酸提取的工艺条件,确定最优低甲氧基果胶制备工艺。结果表明:加入果皮浆液量0.15%的果胶酯酶激活剂碳酸钠,在pH 7.5、45℃的下脱酯50 min,然后采用85℃p、H 3.56、0 min进行酸水解提取果胶。在此工艺条件下制备的果胶甲氧基含量为5.9%,符合低甲氧基果胶标准,且果胶得率较高,为3.0%。

Lowmethoxyl pectin(LMP)was obtained form fresh grapefruit peel by using Na2CO3 as activator to active pectin esterase in fresh peel.Pectin was de-esterified,then extracted,precipitatied and purified.The results showed that de-esterified temperature,pH level,time,and the percent of Na2CO3 to peel and water were 45℃,pH 7.5,50 min and 0.15%,respectively,and the acid-extraction temperature,pH level and time were 85℃,pH 3.5 and 60 min,respectively.Under this condition,the output rate of pectin was 3.0% with the content of methoxyl below 7%,which was in accordance with the national standard for LMP.