热风干燥过程中小白杏色泽的变化及其动力学研究  

Kinetics of colour change of white apricot in XinJiang during hot-air drying

作　　者：闫圣坤[1] 李忠新[1] 王庆惠[1] 孙俪娜[1] 

机构地区：[1]新疆农业科学院农业机械化研究所,新疆乌鲁木齐830091

出　　处：《食品与机械》2017年第2期39-45,共7页Food and Machinery

基　　金：国家自然科学基金地区基金项目(编号:31460397)

摘　　要：为降低小白杏因干燥引起的褐变,保证产品干燥后色泽良好,同时为小白杏干燥设备选型及工艺确定提供理论依据,选择热风干燥的方式,以新疆小白杏为原料,以亮度值(L)、红绿值(a)、黄蓝值(b)、总色差(△E)和褐变指数(BI)为考察指标,研究了热风干燥温度(40,50,60℃)和风速(2,3,4m/s)对新疆小白杏色泽的影响,并在该基础上建立新疆小白杏热风干燥色泽变化动力学模型,有效预测、调节杏褐变程度。结果表明:小白杏在不同风速、不同干燥温度条件下均发生了较为明显的颜色变化,不同热风干燥温度对干燥时间和干燥后杏干色泽均有显著影响,而不同干燥风速对干燥后杏干色泽影响不显著。在不同热风干燥温度和不同风速条件下干燥小白杏的L值和b值随着干燥时间的延长逐渐降低,而a值、△E值和BI值均逐渐升高。小白杏热风干燥过程中颜色参数的反应速率常数k值随着干燥温度的升高而呈现出一定的规律性变化,其中k值受热风温度的影响较大,受风速的影响较小。根据拟合决定系数R2的比较结果,通过动力学方程模拟,得出0阶模型能更好地描述和预测不同风速和不同干燥温度条件下小白杏在热风干燥过程中的颜色变化,而在不同风速和干燥温度条件下小白杏褐变动力学模型模拟效果较好的是1阶模型。该研究为小白杏干燥工艺及杏干产品感官品质控制提供了理论依据。In order to ensure white apricot a good color after drying,avoiding brown appearance,as well as provide the theoretical basis for the selection of drying equipment and process determination of the small white apricot,the hot-air drying method was investigated in this study.The brightness value（L）,red-green value（a）,yellow-blue value（b）,total chromatic aberration（△E）and browning index（BI）were taken as the study indexes,the influence of different hot-air drying temperatures（40,50,60 ℃）and wind speeds（2,3,4m/s）on Xinjiang white apricot was studied.Moreover,the dynamic model of its color change of by hot-air drying was established by using different models to effectively predict and regulate the degree of apricot browning.The results showed that more obvious color changes have occurred to white apricots in the different wind speeds and different hot-air drying temperature conditions,and the different hot-air drying temperatures have significant effects on the drying time and color of dried apricot after drying.However,different drying wind speeds were found no significant effect on the color of dried apricot after drying.Under conditions of different hot-air drying temperatures and wind speeds,the L and b values of dried white apricots were gradually decreased with the extension of the drying time,while △E and BI values gradually increased.In the process of hot-air drying,the reaction rate constant k value of the color parameter of white apricot showed a certain regular changes with the increase of the drying temperature.Of which the k value is greatly affected by the hot-air temperature,and was less affected by the wind speed.According to the comparison result of the fitting determination coefficient R2,by means of kinetic equation simulation,it was concluded that the 0-order model could be used to better describe and predict the color change of white apricot in the hot-air drying process under different wind speeds and drying temperatures.However,under conditions of different wind

关 键 词：小白杏 热风干燥 色泽变化 动力学 

分 类 号：TS255.1[轻工技术与工程—农产品加工及贮藏工程]