Study On The Hydrolysis Rate And Immobilized Of The Lactose Enzyme

This subject mainly studied the hydrolysis rate of e.coli lactase, lactic acid crewe yeast lactase and brittle peak LuWei yeast lactose and the reaction conditions of the best hydrolysis rate,then selected a kind of lactase showing the best hydrolysis rate.With chitosan beads as the carrier, glutaraldehyde as crosslinking agent of the immobilized lactase, to study the optimum immobilization conditions.In the research of lactose enzyme hydrolysis rate, e.coli lactase, lactic acid crewe yeast lactase and brittle peak LuWei yeast lactase were selected to studied,and the three lactases have the different sources.The study used the straight investment type production to explore the low lactose milk by the small kind hydrolysis experiments. Through the comparative analysis of the three kinds of different sources of lactase samples, picked out the best hydrolysis of lactase. The results show that:(1) when the reaction time of2.5h,the hydrolysis rat of lactic acid crewe yeast lactose enzyme was94%, followed by E.coli lactase and brittle peak LuWei yeast lactase;(2) The three kinds of lactases almost had no influence on the physical and chemical index of pure milk, but three kinds of lactases had different taste sweetness due to the lactose enzyme hydrolysis rate are different.Among the three kinds of enzyme,the lactic acid crewe yeast lactase had the heaviest sweetness,followed by the e.coli lactase and the brittle peak LuWei yeast lactase.(3) In the same reaction conditions,the lactic acid crewe yeast lactase had the highest activity among the three kinds of lactose enzyme, followed by e. coli lactase and brittle peak LuWei yeast lactase. And lactic acid crewe yeast lactase was the most suitable for the processing of the milk and the sweet whey.The research of immobilized lactase mainly studied the required conditions and the characteristics.In this study,the chitosan beads was used as the carrier and glutaraldehyde was used as crosslinking agent.This experiment mainly studied some properties of the lactic acid crewe yeast lactase after immobilized, and showed the optimum conditions of the chitosan immobilized lactase through the orthogonal test:the concentration of crosslinking agent glutaric dialdehyde was0.01%, the immobilized time was8h, the pH value was5.5, and the enzyme additives was0.1mg/mL. And the study found that the enzyme properties of the immobilized lactase changed, the optimum pH value of lactose enzyme and immobilized lactase were5.0-5.5and5-6, and the optimum temperature was45℃and55℃respectively.