摘要
目的以枸杞为研究对象,探索枸杞的真空脉动干燥过程中水分变化规律及动力学模型,为改善表面结壳,缩短干燥时间提供理论依据。方法将真空脉动干燥技术应用于枸杞的干燥,研究不同干燥温度(50、55、60、65℃)、真空时间(5、10、20、30 min)和常压时间(2、4、8 min)对枸杞干燥动力学、水分有效扩散系数(Deff)和干燥活化能(Ea)的影响,利用Weibull分布函数对干燥过程进行模拟与分析。结果干燥温度、常压时间和真空时间均对枸杞的干燥有显著影响,当干燥温度60℃,常压时间4 min,真空时间10 min时,干燥时间为284 min;Weibull分布函数能很好地描述枸杞的真空脉动干燥过程;尺度参数α与干燥时间有关,并随干燥温度的升高而降低;干燥温度、真空时间和常压时间对形状参数β的影响较小,β值和干燥方式相关;水分Deff在2.02×10-8～3.56×10-8 m2/s,干燥Ea为36.27 kJ/mol。结论 Weibull分布函数可预测枸杞药材真空脉动干燥过程中的水分脱除规律,对于枸杞干燥过程的预测、调控和工艺优化具有重要意义。
Objective To mitigate Lycii Fructus surface crust and save drying time during drying process,vacuum pulsed drying technology was applied to dry Lycii Fructus so as to investigate moisture diffusion regulation and build the drying model.Methods The effect of different drying temperature (50,55,60,and 65℃),vacuum pressure holding time (5,10,20,and 30min),and atmosphere pressure holding time (2,4,and 8min)on drying characteristics,moisture diffusion coefficients and drying activation energy was explored in vacuum pulsed drying process.Weibull model distribution was used to simulate and analyze Lycii Fructus drying curves.Results All the drying temperature,atmosphere pressure holding time,and vacuum pressure time holding time had significant influence on drying time.When drying temperature,atmosphere pressure holding time,and vacuum pressure time holding time was 60℃,4min,and 10min,respectively,the minimum drying time was achieved to be 284min.Weibull distribution model can be well described the vacuum pulsed drying process ofLycii Fructus.The scale parameter was related to drying time and decreased as drying temperature increased.The drying temperature,atmosphere pressure holding time,and vacuum pressure time holding time had little influence on the shape parameter.The shape parameter was associated with drying method.The moisture diffusion coefficient and activation energy were calculated to be 2.02x 10-8--3.56x 10-8m2/s and 36.27kJ/mol,respectively.Conclusion Wexbull distribution model can well describe the moisture diffusion regulation of vacuum pulsed drying process of Lycii Fructus.The drying result had a great significance for predicting,controlling and optimizing drying process.On the other hand,the research could provide technical basis for industrial drying of Lycii Fructus by vacuum pulsed drying technology.
作者
巨浩羽
赵士豪
赵海燕
刘月英
刁春英
郑志安
高振江
肖红伟
JU Hao-yu;ZHAO Shi-hao;ZHAO Hai-yan;LIU Yue-ying;DIAO Chun-ying;ZHENG Zhi-an;GAO Zhen-jiang;XIAO Hong-wei(College of Biology Science and Engineering,Hebei University of Economies and Business,Shijiazhuang 050061,China;College of Business Administration,Hebei University of Economics and Business,Shijiazhuang 050061,China;College of Engineering,China Agricultural University,B eijing 100083,China)
出处
《中草药》
CAS
CSCD
北大核心
2018年第22期5313-5319,共7页
Chinese Traditional and Herbal Drugs
基金
现代农业产业技术体系建设专项资金资助(CARS-21)
石家庄市科学技术研究开发项目(171170982A)
关键词
枸杞
真空脉动干燥
Weibull分布函数
干基含水率
干燥速率
水分扩散系数
活化能
Lycii Fructus
vacuum pulsed drying
Weibull model distribution
dry basis moisture content
drying rate
moisture diffusion coefficient
activation energy
