The effect of microwave treatment and pressure steaming on the quality of He-fen

To promote the application of microwave treatment and pressure steaming technology in He-fen processing, after husking and whitening the indica rice, microwave treatment was performed with different powers (280, 420, 560, 700 W). Using untreated rice as a control, the physicochemical and pasting characteristics of indica rice were determined. Then the indica milled rice was processed into rice flour by wet milling method. The He-fen was prepared by normal-pressure steaming and pressure steaming respectively. Taking normal pressure steaming treatment as a control, the appearance quality, texture properties, and sensory scores of He-fen were determined. The effects of microwave treatment on the physicochemical and pasting characteristics of indica rice and the quality of He-fen prepared by pressure steaming treatment were analyzed. The results showed that 280 W microwave power treatment had no significant effect on indica chalkiness and amylose content, while the effect on freshness value was significant (P<0.05) with an increasing trend. Under this condition, the viscosity value of the indica rice pasting characteristics increases. With the increase of microwave power, the quality of He-fen firstly increased and then decreased, and He-fen scored the highest and best quality when the microwave power was 280 W. Compared with normal pressure steaming treatment, the brightness of He-fen prepared by pressure steam treatment increased, the hardness increased, the viscosity decreased, and the toughness and ductility increased, all showing significant changes (P < 0.05), and the total sensory evaluation score increased. Therefore, appropriate microwave power (280 W) treatment can improve the freshness of indica rice and its water absorption characteristics, and pressure steaming treatment is beneficial to improve the comprehensive quality of He-fen.