红枣气体射流冲击干燥特性及干燥模型  

Drying Characteristics and Model of Jujube in Air Jet Impingement

作　　者：王立霞[1,2] 兰昊 郑倩雨 郑珊珊 田呈瑞 田洪磊[1] 肖旭霖 WANG Lixia;LAN Hao;ZHENG Qianyu;ZHENG Shanshan;TIAN Chengrui;TIAN Honglei;XIAO Xulin(College of Food Engineering and Nutritional Science,Shaanxi Normal University,Xi’an 710119,China;College of Life Science and Food Engineering,Shaanxi Xueqian Normal University,Xi’an 710100,China)

机构地区：[1]陕西师范大学食品工程与营养科学学院,陕西西安710119 [2]陕西学前师范学院生命科学与食品工程学院,陕西西安710100

出　　处：《食品科学技术学报》2022年第2期131-140,共10页Journal of Food Science and Technology

基　　金：陕西省科技计划项目(2021-NY-132,2019-NY-133);2021年陕西省体育局常规课题(2021349);陕西省大学生创新创业训练计划项目(7299,2019DC035)。

摘　　要：由于红枣收获后品质快速下降,探讨适合红枣的加工方法以便延长红枣的保藏期非常重要。探究了干制条件对红枣气体射流干燥特性的影响,以便提高干制红枣品质,缩短干制时间,获取干燥活化能,优选干燥模型。选用自制气体射流冲击干燥设备干制红枣,研究风速(8.5、10.0、12.0 m/s)、风温{60、65、70℃,变量[70℃(5 h)+65℃(8 h)+55℃]}对红枣水分比和干燥速率、水分有效扩散系数及活化能的影响,通过DPS数据统计软件对8个干燥模型(Lewis、Page、Modified Page、Wang&Singh、Henderson&Pabis、Approximation of diffusion、Logarithmic、Simplified Fick's diffusion)进行拟合筛选。与大多数食品材料的干燥特性一致,红枣的气体射流冲击干燥过程主要为降速干燥。温度对整个干燥过程中参数的变化影响较大,温度越高,水分扩散越快,水分比下降越快,干燥速率越高。最高有效扩散系数为1.22133×10^(-9) m^(2)/s,所需最小活化能为10.39 kJ/mol。使用8个模型进行拟合,研究发现Logarithmic模型的参数系数(R^(2))值为0.999801,均方根误差(RMSE)值为0.002913,卡方值(χ^(2))为9.332000×10^(-6),该模型为描述红枣气体射流冲击干燥的最优模型。温度与风速均对干燥曲线、干燥速率曲线、水分有效扩散系数和活化能有影响,在温度70℃(5 h)+65℃(8 h)+55℃,风速12.0 m/s的条件下干燥效果较佳。Due to the rapid decline of jujube quality after harvest,it is very important to explore suitable processing methods to extend the preservation period of jujube.Therefore,this study explored the influence of dry conditions on the drying characteristics of jujube in air jet impingement drying,so as to improve the quality of dry jujube,shorten the drying time,obtain dry activation energy,and optimize the drying model.Self-made air jet impingement drying equipment was used to study the influence of wind speed(8.5 m/s,10.0 m/s,12.0 m/s),wind temperature{60℃,65℃,70℃,[70℃(5 h)+65℃(8 h)+55℃]}on jujube moisture ratio,drying rate,effective moisture diffusion coefficient and activation energy.Eight drying models(Lewis,Page,Modified Page,Wang&Singh,Henderson&Pabis,Approximation of diffusion,Logarithmic,Simplified Fick's diffusion)were fitted and screened by DPS data statistical software.Consistent with the drying characteristics of most food materials,the air jet impingement drying process of jujube is mainly falling-rate drying.Temperature had a great influence on the changes of parameters in the whole drying process.The diffusion of water and the decline of moisture ratio were faster with the temperature increasing and the drying rate was also the higher.The highest effective diffusion coefficient was 1.22133×10^(-9) m^(2)/s,the minimum activation energy required was 10.39 kJ/mol.Eight models were used for fitting.It was founded that the parameter coefficient(R^(2))value of Logarithmic model was 0.999801,the root mean square error(RMSE)value was 0.002913,the Chi-square(χ^(2))value was 9.332000×10^(-6),and this model was the optimal model.Both temperature and wind speed had effects on drying curve,drying rate curve,effective moisture diffusion coefficient and activation energy.The better drying effect was obtained at the temperature of 70℃(5 h)+65℃(8 h)+55℃and the wind speed of 12.0 m/s.

关 键 词：红枣 气体射流冲击 干燥特性 干燥模型 Logarithmic模型 

分 类 号：TS255.3[轻工技术与工程—农产品加工及贮藏工程]