白玉菇中短波红外干燥特性及动力学模型

为提高白玉菇的货架期,采用中短波红外线对白玉菇进行干燥,考察了干燥温度(60、70、80、90℃)和干燥功率(675、900、1125、1350 W)对白玉菇干燥特性的影响,并通过7种常用的农产品干燥模型对干燥过程进行了拟合,建立了白玉菇中短波红外干燥的动力学模型。研究结果表明:干燥温度和干燥功率对白玉菇的干燥过程均有影响,但干燥温度对干燥过程影响更大,干燥温度越高,干基含水率下降越明显。白玉菇干燥过程由内部水分扩散控制,降速阶段为主要阶段。Page模型的预测值与实验值具有较高的拟合度,能够较准确地反映白玉菇红外干燥过程,可以用来定量描述不同干燥温度和不同干燥功率下白玉菇的红外干燥过程规律。固定干燥功率为1125 W时,水分有效扩散系数随着干燥温度的升高而增大,当干燥温度从60℃升高到90℃时,水分有效扩散系数从2.723×10^-9 m^2/s升高到9.088×10^-9 m^2/s;固定干燥温度为70℃时,水分有效扩散系数随着干燥功率的升高而增大,当干燥功率从675 W增加到1350 W时,水分有效扩散系数从4.847×10^-9 m^2/s升高到5.243×10^-9 m^2/s。白玉菇中短波红外干燥活化能为39.45 kJ/mol。本研究旨在对白玉菇的中短波红外干燥工艺设计、设备选型及生产控制提供理论参考。

Drying Characteristics and Kinetics Model of White Hypsizygus marmoreus with Medium and Short Wave Infrared Radiation

In order to improve the shelf life of white Hypsizygus marmoreus,the medium and short wave infrared radiation was used to dry white Hypsizygus marmoreus,and effects of drying temperature(60,70,80,90℃)and drying power(675,900,1125,1350 W)on drying characteristics of white Hypsizygus marmoreus were investigated.Drying process were fitted through 7 commonly used drying models of agricultural products and a kinetics model of middle and short wave infrared drying in white Hypsizygus marmoreus was established.Results showed that both drying temperature and drying power had effects on the drying process of white Hypsizygus marmoreus.However,drying temperature had a greater impact on the drying process.The moisture content of drying base was obviously declined with the increase of drying temperature.Drying process was controlled by internal moisture diffusion,and the slowdown phase was the main stage.The predicted value of the Page model fitted well with the experimental value,which could accurately reflect the infrared drying process of the white Hypsizygus marmoreus,and could be used to describe the infrared drying process of white Hypsizygus marmoreus quantitatively under different drying temperatures and powers.When the drying power was 1125 W,the effective moisture diffusion coefficient of white Hypsizygus marmoreus was increased with the increase of drying temperature,which was from 2.723×10^-9 m^2/s to 9.008×10^-9 m^2/s accompanied by the drying temperature raising from 60℃to 90℃.At drying temperature of 70℃,the effective moisture diffusion coefficient increased from 4.847×10^-9 m^2/s to 5.243×10^-9 m^2/s when the drying power increased from 675 W to 1350 W.The midium and short wave infrared drying activation energy of white Hypsizygus marmoreus was 39.45 J/mol.This study aims to provide the theoretical reference to the medium and shot wave infrared radiation drying process design,equipment selection,and production control of white Hypsizygus marmoreus.