摘要
干燥对油茶籽贮藏、加工和茶油质量极其重要.为了优化干燥工艺,降低干燥能耗,研究了热风干燥、微波干燥和自然干燥3种方法对油茶籽中油脂稳定性的影响,考察了温度和堆积密度对油茶籽干燥特性的作用规律,采用3种不同模型对油茶籽干燥过程进行拟合,建立了干燥数学模型.结果表明:油茶籽适宜采用热风干燥,干燥速率随着温度的升高和堆积密度的减小而增大;在40、55、70℃下,油茶籽干燥至相对安全储藏水分所需时间分别为20、15、13 h;堆积密度为322、354、430、442 kg/m3时,对应的干燥时间约为15、20、22、25 h.常用的3种指数干燥模型的线性回归分析表明,Page模型能较好地描述油茶籽的热风干燥过程,所得理论值和试验值之间的平均相对误差为5.72%,说明该模型能较准确地预测油茶籽干燥过程中的干燥速率及水分含量.
The drying procedure is extremely important to the storage and processing of Camellia oleifera seed and to the quality of Camellia oil. In order to optimize the drying technology and reduce energy consumption, the effects of hot-air drying, microwave drying and natural drying on the stability of oil were analyzed, and the law of the effects of temperature and bulk density on the drying characteristics of Camellia oleifera seed is investigated. Then, a mathematical model describing the drying procedure is established by integrating the three models. The results show that （1） hot-air drying is more suitable for Camellia oleifera seed; （2） the drying rate increases with the increase of temperature and with the decrease of bulk density; （3） it takes 20, 15 and 13 h respectively to attain a relative safe moisture content for storage at the drying temperatures of 40, 55 and 70 ℃ ; and （4） the drying time cost reaches 15, 20, 22 and 25 h when the bulk densities are 322, 354,430 and 442 kg/m3 , respectively. Moreover, it is demonstrated by the linear regression of the three common drying models that the Page model accurately describes the hot-air drying process of Camellia oleifera seed, with an average relative error of 5.72% between theoretical values and experimental ones. It is, thus, concluded that, for the drying of Camellia oleifera seed, the Page model can predict the drying rate and moisture content more accurately.
出处
《华南理工大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2010年第8期116-120,共5页
Journal of South China University of Technology(Natural Science Edition)
基金
广东省科技计划项目(2009B030802043
2009B020201007)
关键词
油茶籽
干燥特性
数学模型
Camellia oleifera seed
drying characteristic
mathematical model
