研究了传统加热、微波加热和超声-微波协同加热对粳米淀粉和糯米淀粉回生特性的影响。结果表明:粳米淀粉对热作用的敏感性更高,在相同的贮存时间下,微波加热和超声-微波协同加热的粳米淀粉凝胶较传统加热的样品回生速率慢,凝胶强度增加和酶解力下降较小,并且微观结构上更致密平整。原因在于微波加热和超声-微波协同加热方式下淀粉颗粒膨胀破裂不充分,直链淀粉浸出的量相对较少,导致淀粉凝胶重结晶有序化程度较低,从而抑制淀粉回生过程。
Retrogradation properties of normal and waxy rice starch gels prepared by conventional heating,microwave heating and ultrasonic-microwave synergistic heating were investigated in this study.Our results showed that non-waxy rice starch was more susceptible to heat treatments.During the same period,the retrogradation rate,the changes of gel strength,and the hydrolysis degree of normal rice starch gelatinized by microwave and ultrasonic-microwave synergistic heating were significantly slower than that by conventional heat.The results also found that the microstructure of non-waxy rice starch gels obtained from microwave and ultrasonic-microwave synergistic heat treatments was denser.The retardation mechanism of microwave heating and ultrasonic-microwave synergistic heating on starch retrogradation is probably due to the less broken granules and lower leached amylose.