以乳清为原料酶法水解乳糖条件的研究

Study on Enzymatic Hydrolysis of Lactose in Whey

乳糖溶解性差、甜度低,加之部分人群具有乳糖不耐症等原因,乳清中乳糖的利用率相对较低。利用β-半乳糖苷酶对乳清中的乳糖进行水解,既可以改善乳糖的溶解性能和甜度,又有利于提高乳清中乳糖的利用率。本实验通过研究乳清中乳糖的浓度、β-半乳糖苷酶的使用量、水解液温度、水解液pH对乳糖水解度的影响,确定了以乳清为原料酶法水解乳糖的适宜条件,即乳糖浓度15%、β-半乳糖苷酶的使用量为90U/g乳糖、水解液温度40℃、水解时间3h、水解液pH值6.5,在此条件下水解度为68%。

Bad solubility, low saccharinity of lactose and lactose intolerance have caused low availability of whey. Now β - galaetosidase was applied for hydrolysis of lactose in whey. The treated lactose in whey improved saccharinity and solubility thus easily utilized. Papers studied the effects of initial lactose concentrations and enzyme dosage, temperature and pH on degree of lactose hydrolysis. Orthogonal test was designed to identify opt^um hydrolysis conditions for yielding most monomeric saccharides. The optimum conditions of hydrolysis for lactase was that substrate concentration 15%, 40 ℃, 3 h and of lactase dosage 90 U/g. Under these conditions the hydrolysis degree is 68%.