不同湿度条件下白肋烟晾制期间烟叶水分的变化

Moisture Metabolism of Burley Tobacco Leaf during Curing Process under Different Humidity Conditions

研究了自然条件和人工调控条件下,不同湿度处理的晾房中白肋烟叶片晾制期间总水含量和自由水含量的变化趋势,以探讨人工调控的条件下白肋烟晾制的合适湿度。结果表明:人工调控条件下,3个不同湿度处理的晾房中叶片总水含量在晾制开始的前2周有一个快速下降的过程,然后维持在较低的水平,并维持到晾制结束。晾制前期的湿度对总水含量变化的影响显著,高湿对叶片失水有缓冲作用,在第1周内含水量下降不明显,低湿则加速叶片脱水。晾制开始时,烟株上部叶片含水量最高,中部叶片次之,下部叶片最低,但晾制结束时各部位叶片含水量相近。与人工调控的晾房相比,自然条件下各湿度处理叶片总水含量的变化相对缓慢。对于白肋烟叶片自由水含量,不同条件下晾制期间均呈明显的下降趋势。低湿处理的晾房中下降速度最快,中湿处理次之,高湿处理的晾房中下降速度最慢。中湿晾制条件有利于优质白肋烟的形成。

The changes of total water content and free water content in burley tobacco leaf during the curing process in different humidity treatments controlled under both the artificial and natural conditions were studied respectively. The results showed that total water content in burley tobacco leaf decreased quickly during the first two weeks of air-curing in three humidity treatments, and then kept stable until the end of curing under the artificial barns. High humidity condition could reduce the water loss rate of tobacco leaf, especially in the first week of the curing period, and the total water content changed little. However, low humidity condition could speed up the rate of water loss. In the beginning of the curing, the total water content in upper leaf was highest and lowest in the lower leaf, but at the end of the curing period, the water content at different leaf positions was almost at the same level. Contrasted with what happened in the artificial control, the change of total water content leaf in the natural barn was less obvious. The free water content in leaf under different curing condition decreased obviously in the air-curing period, and its decreasing rate in low humidity was the highest and that in high humidity treated barn was the lowest.