摘要
【目的】探讨烟丝在干燥环境中贮藏时,不同保润剂对烟丝保润效果及水分散失动力学的影响。【方法】以传统烟草保润剂甘油和新型烟草保润剂乳酸钾为代表,将喷洒了保润剂的烟丝置于干燥环境中测试其水分含量的变化。通过对4种常见薄层干燥模型进行非线性拟合,确定烟丝干燥速率常数,并采用Fick第二定律扩散模型进行动力学分析,得到烟丝内部水分的有效扩散系数。【结果】甘油和乳酸钾都能够降低烟丝的干燥速率常数和水分有效扩散系数。当甘油添加量为2%时,烟丝的干燥速率常数和有效扩散系数分别从0.413 8,2.348 6×10-10 m2/s降至0.339 2,1.702 9×10-10 m2/s,而添加2%乳酸钾的烟丝干燥速率常数和有效扩散系数分别为0.255 9,1.593 8×10-10 m2/s。【结论】乳酸钾具有优于甘油的保润性能。保润剂能够有效降低烟丝的干燥速率常数和水分有效扩散系数,且干燥速率常数和水分有效扩散系数随其添加量的增加而降低。
[Objective] Effects of different humectants on water-holding capacity and moisture transfer kinetics of tobacco during storage in dry environment were investigated. [Method] Tobacco leaves sprayed with traditional humectant glycerol and new huectant potassium lactate were stored in dry environment and water contents in tobacco leaves were measured during the storage. Based on the fitting according to 4 com- mon dynamic models, the drying rate constant was determined. Besides, the diffusion model based on Fick＇ s second law was applied to determine the effective diffusion coefficient. [Result] Both glycerol and potassi- um lactate decreased the drying rate constant and the effective diffusion coefficient of the tobacco leaves. When 2% glycerol was added,drying rate constant decreased from 0. 413 8 to 0. 339 2 and the effective dif- fusion coefficient decreased from 2. 348 6× 10-10 m2/s to 1. 702 9× 10-10 m2/s. When 2% potassium lactate was used,they decreased to 0. 255 9 and 1. 593 8× 10-10 m2/s,respectively. [Conclusion] Potassium lactate was better than glycerol in decreasing dry rate constant and effective diffusion coefficient of tobacco leaves and they could be further decreased when increasing the adding amount of humectants.
出处
《西北农林科技大学学报（自然科学版）》
CSCD
北大核心
2014年第1期96-101,共6页
Journal of Northwest A&F University(Natural Science Edition)
基金
国家烟草专卖局资助项目"卷烟烟气味觉特征及调控研究"(110200901002)
关键词
烟草
保润剂
干燥动力学模型
有效扩散系数
干燥速率常数
tobacco
humectants
drying dynamic models
effective diffusion coefficient
drying rate constant
