食品科学2017，Vol.38Issue(13)：53-59,7.DOI:10.7506/spkx1002-6630-201713009
单片物料厚度对胡萝卜红外薄层干燥水分迁移的影响
Effect of Single Material Thickness on Moisture Transfer during Infrared Thin-Layer Drying of Carrot
摘要
Abstract
In order to improve the drying rate vt and the quality of dried vegetables,in our previous work,single material thickness (h),material thickness (δ),drying temperature (7),power density (g) and radiation distance (L) were selected as factors affecting infrared radiation thin layer drying of carrot slices and optimized by one-factor-at-a-time method and orthogonal array design,and the analysis of variance showed that h value had a significant effect on the experimental results.In an effort to further explore the effect of h value on moisture migration during infrared thin layer drying,this study examined the transverse relaxation time (T2x),peak area (A2x) and peak ratio (S2x) as a function of single material thickness (h) and 4 other factors by low-filed nuclear magnetic resonance (LF-NMR).The mobility of free water dropped by over 60％ in the middle stage of drying at each h value,with the moisture content tending to be zero and immobilized and bound water increasing not more than three times and three to six times,respectively.After 120 min of drying,the percentage of free water in the total peak area of water decreased to below 15％ at each h value,while the percentage of bound water rose to above 65％,and the percentage of immobilized water showed two peaks.The effective water diffusion coefficient (Deff) was reduced by up to 30％ with increasing h value.The Page model provided good prediction of changes in moisture ratio during infrared thin layer drying.Results from this study can provide a theoretical reference to further explore infrared drying of agricultural crops and to develop crop drying equipment.关键词
低场核磁共振/红外辐射/胡萝卜/单片物料厚度/薄层干燥/水分迁移Key words
low-filed nuclear magnetic resonance (LF-NMR)/infrared radiation/carrot/single material thickness/thin layer drying/moisture transfer分类
轻工纺织引用本文复制引用
孙传祝,石东岳,王相友,魏忠彩..单片物料厚度对胡萝卜红外薄层干燥水分迁移的影响[J].食品科学,2017,38(13):53-59,7.基金项目
国家自然科学基金面上项目(31271908) （31271908）
