【摘要】 稻谷间歇微波干燥可消除籽粒过热焦变,实现干燥效能提升,但干燥后稻谷品质存在易玻璃化转变而裂变率增加的问题。为综合提升稻谷干燥效能与品质,分别测定了缓苏比不同和缓苏比相同下的4种加热缓苏周期(TR1, TR2, TR3, TR4)微波干燥稻谷的失水性能和玻璃化转变温度、裂变率。基于2种增长模型(Weibull模型、Logistic模型),比较了不同加热缓苏周期下间歇微波干燥稻谷裂变率的增长性能,考察了其玻璃化转变与裂变率间的关联。结果显示:随着缓苏比增加,在加热缓苏周期中具有相同加热时间已干燥稻谷的含水率依次增大,但其玻璃化转变温度、裂变率依次减小;加热缓苏时间比相同而周期缩短,稻谷的玻璃化转变温度、裂变率均低;经TR4微波干燥的稻谷的总裂变率仅为7.67%,显著低于其他3种工艺(p<0.05);以Weibull模型预测间歇微波干燥稻谷的裂变率增长的准确度高于Logistic模型(R~2≥0.9783)。研究结果可为深入研究稻谷间隙微波干燥机理提供参考。更多还原

【Abstract】 Intermittent microwave drying of rice can eliminate the overheated coking of the grains and improve the drying efficiency.However, the quality of dried rice still has the problem of easy glass transition and crack ratio increasing.In order to comprehensively improve the efficiency and quality of rice drying, the water loss performance, glass transition temperature and crack ratio of dried rice in four heating-tempering cycles( TR1, TR2, TR3, and TR4) by different tempering ratios and same tempering ratio were measured respectively.Based on two growth models(Weibull model, Logistic model), the growth performance of rice crack ratio of intermittent microwave drying under different heating-tempering cycles were compared, and the relationship between its glass transition and crack ratio were investigated.The results show that with the increase of the tempering ratio, the moisture content of the dried rice with the same heating time in the heating-tempering cycle increases successively, but the glass transition temperature and crack ratio decrease successively.Under the same tempering ratio and shortened cycle, the glass transition temperature and crack ratio of rice are both low.The total crack ratio of rice dried by TR4 microwave is only 7.67%, which is significantly lower than the other three processes(p<0.05).Moreover, the Weibull model is more accurate than the Logistic model(R~2≥0.9783) in predicting the crack ratio growth of intermittent microwave drying of rice.This result can provide a reference for further research on the mechanism of intermittent microwave drying of rice.更多还原