硫酸水解法去除谷氨酸母液中的焦谷氨酸

摘要

焦谷氨酸没有鲜味,是谷氨酸产品中的无效成分,其安全性尚无定论.控制谷氨酸浓度为16 g/dL,焦谷氨酸的浓度为3.2 g/dL,实验研究了水解温度、硫酸加入量、水解时间等因素对降低谷氨酸母液中焦谷氨酸含量的影响.在保证谷氨酸回收率的基础上,确定出使焦谷氨酸含量达到1％及以下的最优水解组合:水解温度(95±5)℃、浓硫酸加入量(30％,V/V)、水解时间(2 h).在上述实验中,焦谷氨酸的初始含量均为20％.通过改变初始焦谷氨酸含量为20％～35％,最优水解组合下,水解后焦谷氨酸含量为0.96％～1.0％,仍可达到1％以下.%Pyroglutamic acid (PCA) is not an effective component in glutamic acid product because it has no flavor.It is no conclusion whether PCA is safe to be eaten.Controll glutamic acid concentration to 16 g/dL and PCA concentration to 3.2 g/dL,the hydrolysis temperature,sulfuric acid addition and hydrolysis time could reduce the content of PCA in glutamic acid mother liquor.The optimal combination of hydrolysis is determined on the basis of ensuring the content of PCA is less than or equal to 1 ％ and the recovery rate of glutamic acid is high.The optimal combination of hydrolysis is:hydrolysis temperature of (95±5) ℃,sulfuric acid addition of 30％ (V/V) and hydrolysis time of 2 h.In these experiments,the initial PCA content is 20％.Through increasing sulfuric acid addition from 20％ to 35％,the PCA content in glutamic acid hydrolyzate could be 0.96～1.0％,which can decline to 1 ％.