不同稻谷干燥方式对浸泡前后大米品质的影响

Effects of Different Drying Methods on Rice Quality Before and After Soaking

为探究不同稻谷干燥方式对浸泡前后大米理化性质及食味品质的影响,以经过自然干燥和热风干燥处理的同一品种粳米为主要原料,探究不同稻谷干燥方式对浸泡前后大米的水分含量、水分分布、微观结构、晶型结构、糊化特性、碘蓝值、食味值以及质构特性的影响。结果表明,热风干燥组大米裂纹较多,相对结晶度、回生值、糊化温度显著低于(P<0.05)自然干燥组,而崩解值、最终黏度、米饭黏弹性和食味值显著高于(P<0.05)自然干燥组;热风干燥组大米在浸泡初期吸水率显著高于(P<0.05)自然干燥组,且当浸泡30 min时两组大米的水分含量基本达到饱和,浸泡后,两组大米的裂纹数量和宽度均明显增大,相对结晶度分别降低了1.03%~1.98%、糊化温度降低了2.45~3.40℃;峰值黏度、谷值黏度、崩解值、最终黏度、回生值和米饭黏弹性显著增大(P<0.05),碘蓝值增加了15.60%~21.26%,米饭食味值增加至84.73~85.46。综上所述,浸泡提升了两组米饭的品质,且热风干燥组米饭品质更好。

In order to explore the effects of different rice drying methods on physicochemical properties and taste quality of rice before and after soaking,the same variety of japonica rice after natural drying and hot air drying was used as the main raw material to explore the effects of different rice drying methods on water content,water distribution,microstructure,crystal structure,gelatinization characteristics,iodine blue value,taste value and texture characteristics of rice before and after soaking.The results showed that there were more cracks in the hot-air drying group,and the relative crystallinity,recovery value and gelatinization temperature were significantly lower than those in the natural drying group(P<0.05),while the disintegration value,final viscosity,rice viscoelasticity and taste value were significantly higher than those in the natural drying group(P<0.05).The water absorption rate of rice in the hot-air drying group was significantly higher than that in the natural drying group(P<0.05)at the beginning of soaking,and the water content of rice in the two groups basically reached saturation after soaking for 30 min.After soaking,the number and width of cracks in the two groups increased significantly.The relative crystallinity and gelatinization temperature decreased by 1.03%~1.98%and 2.45~3.40℃,respectively.The peak viscosity,valley viscosity,disintegration value,final viscosity,recovery value and viscoe-lasticity of rice were significantly increased(P<0.05),the iodine blue value was increased by 15.60%~21.26%,and the taste value of rice was increased to 84.73~85.46.