烘烤过程中鲜烟叶干燥特性参数筛选

Screening of drying characteristic parameters of fresh tobacco leaves during curing

筛选影响烟叶烘烤过程中失水速率的鲜烟叶干燥特性参数,为构建基于鲜烟叶素质的失水速率模型提供参数指导,以湖北省恩施烟区烤烟品种云烟87、K326、鄂烤2号不同部位烟叶为试验材料,运用相关性分析、多重贡献性诊断、逐步回归分析和优势分析探寻鲜烟叶参数与其烘烤过程中失水速率的关系。结果表明,鲜烟叶参数、烘烤过程中失水速率变异较大,变异系数分别达5.98%~18.58%、14.55%~24.33%。简单相关系数表明,鲜烟叶含水率、叶片厚度、叶长、叶宽、叶中部主脉直径、叶尖部主脉直径、叶基部支脉直径与部分阶段失水速率达显著相关水平,但鲜烟叶各项指标间也存在多重共线性。采用逐步回归方法消除共线性影响后(回归方程通过显著性检验,P<0.01),借助优势分析法(DA)计算出各指标对烟叶烘烤各阶段的平均贡献度,在烘烤条件一致下,筛选出鲜烟叶叶片厚度、叶宽、叶基部支脉直径、叶尖部主脉直径、叶中部主脉直径是烟叶烘烤过程中失水特性的关键参数。

The drying characteristic parameters of fresh tobacco leaves affecting water loss rate during curing were screened to provide parameter guidance for constructing the water loss rate model based on quality of fresh tobacco leaves.Different parts of flue-cured to⁃bacco varieties Yunyan 87,K326 and Ekao 2 in Enshi tobacco growing area of Hubei Province were used as experimental materials.Correlation analysis,multiple contribution diagnosis,stepwise regression analysis and dominance analysis were used to explore the re⁃lationship between fresh tobacco parameters and water loss rate during curing.The results showed that the parameters of fresh tobacco leaves and water loss rate varied greatly during curing,and the coefficients of variation were 5.98%~18.58%and 14.55%~24.33%,re⁃spectively.The simple correlation coefficient showed that correlation of the moisture content,leaf thickness,leaf length,leaf width,main vein diameter in the middle of the leaf,diameter of the main vein of the tip of the leaf,and diameter of the branch vein at the base of the leaf with the rate of water loss in some stages reached a significant level,but there were multiple collinearities among index⁃es of fresh tobacco.After the collinearities were eliminated by the stepwise regression method(regression equation passed significance test,P<0.01),the average contribution degree of each index to each stage of tobacco curing was calculated with the help of the domi⁃nance analysis method(DA).Under the same baking conditions,the leaf thickness,leaf width,leaf base branch vein diameter,leaf tip main vein diameter and leaf middle main vein diameter of fresh tobacco leaves were selected as the key parameters of water loss characteristics during tobacco baking.