远红外辐射温度对猕猴桃干燥水分迁移的影响  

Effects of far-infrared radiation temperature on the moisture transfer of kiwifruit slices

作　　者：曾雅 刘云宏[1,2] 张嘉怡 席慧涵 胡润润 ZENG Ya;LIU Yun-hong;ZHANG Jia-yi;XI Hui-han;HU Run-run(College of Food and Bioengineering, Henan University of Science and Technology,Luoyang, Henan 471023, China;Henan Engineering Technology Research Center of Agricultural Product Drying Equipment, Luoyang, Henan 471023, China)

机构地区：[1]河南科技大学食品与生物工程学院,河南洛阳471023 [2]农产品干燥装备河南省工程技术研究中心,河南洛阳471023

出　　处：《食品与机械》2019年第8期143-147,188,共6页Food and Machinery

基　　金：国家自然科学基金项目(编号:U1404334);河南省高校科技创新人才资助计划(编号:19HASTIT013);河南省科技攻关项目(编号:172102310617);国家大学生创新训练计划(编号:201810464010)

摘　　要：利用低场核磁共振技术研究不同远红外辐射温度对猕猴桃内部水分状态与迁移的影响规律。结果表明:随着辐射温度的升高,猕猴桃所需干燥时间缩短,在120,160,200,240,280℃的辐射温度下平均干燥速率之比为1.00:1.30:1.54:2.00:2.50;远红外辐射干燥猕猴桃的有效水分扩散系数为2.85×10-10~7.03×10-10 m2/s,提高辐射温度有利于增大扩散系数值;猕猴桃中存在自由水、不易流动水和结合水3种状态水分;随着干燥的进行,自由水的相对比例逐渐减少,辐射温度由120℃升至280℃时,自由水去除所需时间可缩短75%;在干燥前期会有部分水分由高自由度向低自由度转变;干燥结束时,样品中残余水分以结合水为主;提高辐射温度可以促进各种水分状态之间的转变以及水分的去除。In order to explore the water diffusion characteristics of kiwifruit during far-infrared radiation drying,low-field nuclear magnetic resonance(LF-NMR)technology was applied to analyze the influence of radiation temperature on internal water states and moisture migration of kiwifruits during drying.The results showed that drying time decreased significantly with the increasing of radiation temperature,and the ratio of average drying rates at radiation temperatures of 120,160,200,240 and 280℃were 1.00:1.30:1.54:2.00:2.50 respectively.The effective moisture diffusivity values was in the range of 2.85×10-10~7.03×10-10 m^2/s,which could be improved with the increase in radiation temperature.NMR results showed that the water states in kiwifruits included free water,immobilized water and bound water.With the proceeding of drying process,the relative proportion of free water in kiwifruits decreased gradually,and the removal time of free water reduced by 75% as radiation temperature increased from 120 to 280 ℃.At the early stage of drying,some of the moisture with high degree of freedom moved to the moisture with low degree of freedom.Up to the end of drying,bound water was the main component left in the sample.And higher radiation temperature could accelerate the migration and removal of moisture.

关 键 词：猕猴桃 远红外辐射 干燥特性 低场核磁共振 水分迁移 

分 类 号：TS255.3[轻工技术与工程—农产品加工及贮藏工程]