干燥方式对大米回生情况的影响

目的:探究不同干燥方法对已熟化大米回生情况的影响。方法:采用热风、微波、近红外以及真空-微波四种干燥方式对已充分糊化的大米进行干燥,采用快速粘度分析仪（Rapid Visco Analyser,RVA）、差示扫描量热仪（Differential Scanning Calorimeter,DSC）、X-射线衍射仪（X-ray Diffraction,XRD）以及扫描电子显微镜（Scanning Electron Microscope,SEM）等手段观察不同干燥方法对大米结构的影响。结果:这四种干燥方法均能使大米保持较好的糊化状态,回生程度较小;但不同的干燥方式对大米的组织结构有不同的影响,其中真空微波干燥影响最大,出现较大孔洞,结构蓬松,在宏观上的表现为复水率最高（5.2%）。 

Effects of drying methods on the retrogradation of rice

Hot- air drying,microwave drying,near infrared drying and vacuum- microwave drying were used to dry the fully gelatinized rice in order to reduce the degree of retrogradation.Rapid viscosity analyzer( RVA),differential scanning calorimeter( DSC),X- ray diffractometer( XRD),and scanning electron microscope( SEM) etc. were applied to observe the effects of different drying methods on the structure of rice. Results showed that the four kinds of drying method can well keep the good state of gelatinized rice and to a lesser extent of retrogradation.However,different drying methods impacted differently on rice tissue structure.The microwave vacuum drying had the greatest impact,which resulted in larger pores,and fluffy structure,as well as the highest( 5.2%) rehydration rate in the macro performance.