Abstract:

To probe into the effect of glutaminase modification on the functional properties of rice glutelin, rice glutelin was prepared in our laboratory and enzymatically modified with glutaminase, and rice glutelin and its modification products at different treatment time points were analyzed for their solubility, emulsifying properties, foaming properties, viscosity, waterbinding capacity, oil-binding capacity and so on. The results showed that glutaminase modification could improve various functional properties of rice glutelin. After glutaminase modification, the solubility of rice glutelin was obviously increased (up to 96.99%). The modification products of rice glutelin in the hydrolysis time range of 1 to 12 h had the best emulsifying properties, and after hydrolysis for 1 to 5 h, the strong acid resistance of rice glutelin was remarkably improved and an optimal foaming capacity was observed. However, its foam stability and viscosity both gradually decreased with increasing reaction time. Furthermore, glutaminase modification resulted in a 1.75 to 2.03-fold increase in water-binding capacity and a 1.58 to 1.94- fold increase in oil-binding capacity.

Key words: rice glutelin, glutaminase, deamidation, functional property