The Study Of Temperature Stability Amylase Used In The Improvement Of Rice Quality And Starch Saccharification

The temperature stability amylase is a kind of amylase whose optimum temperature exceeds60℃, which has the characteristics that a general enzyme should have, such as optimum temperature, optimum pH and specific. Recently, the methods of improving rice quality at home and abroad has cross-breeding, mutation breeding, the improvement of cooking technology, et al. Improving the quality of rice by amylase is also one of them. Starch saccharification is the process of a hydrolysis of starch where starch is transformed into monosaccharides, disaccharides and oligosaccharides. Starch saccharification has broad application prospects, mainly used in the preparation of oligosaccharides, bioenergy, wine industry and other aspects.In this thesis, we studied the application of temperature-stability amylase in the improvement of rice quality.The results are as follows:(1)using the sigma rice starch as raw materials, we preliminary studied and found that the temperature-stability amylase can hydrolysis the amylase and have no significant effect for amylopectin content.(2)using8u/g temperature-stability amylase to effect the rice and cooking30min,we found that enzyme1458can make the hardness of rice decline4.9511kg and the viscosity of rice rise0.6349kg,while enzyme0613can make the hardness of rice decline2.6431kg and the viscosity of rice rise06708kg.(3)In enzyme concentration between Ou/g and8u/g,the hardness of rice is negatively correlated with the enzyme concentration,while in enzyme concentration between Ou/g and4u/g, the viscosity of rice is positively correlated with the enzyme concentration,and enzyme concentration has little effect for the viscosity of rice after4u/g.(4)As the number of storage days is between0and7,the retrogradation of rice is positively correlated with the storage time,while after7days,the retrogradation is little affected by the storage time.(5)In enzyme concentration between Ou/g and8u/g, the retrogradation of rice is negatively correlated with the enzyme concentration.This paper further studied the mechanism of action of the amylase modifying the hardness,viscosity and retrogradation of rice,and the results are as follows:(1)The temperature-stability amylase can hydrolysis the amylase of rice,which can make the hardness of rice decrease and the viscosity of rice rose, and improve anti-retrogradation quality of rice.(2)The enzyme1458can reduce the length and increase the number of the branch chain in rice amylopectin,which can improve anti-retrogradation quality of rice.Finally, using the corn starch as raw materials and make liquefaction and saccharification at the same time,we studied the effect of corn saccharification for the temperature-stability amylase. The results are as follows:the amylase can make corn starch hydrolysis into glucose,isomaltose and maltose, and the saccharification yield can reach to118%.