烤烟下部烟叶在烘烤过程中叶绿素的降解研究

目的]研究下部烟叶叶绿素在烘烤过程中的变化趋势。方法]叶绿素色素与类胡萝卜素用80%丙酮研磨法提取,其含量用分光光度法测定,研究下部烟叶叶绿素在烘烤过程中的降解。结果]下部鲜烟叶叶片的叶绿素含量最高的是云203,其次为PVH19,含量最低的是云97;类胡萝卜素含量最高的是PVH19,含量最低的是中烟100。变黄期末,叶片及烟筋叶绿素相对降解量占到80.0%~95.0%以上;叶片类胡萝卜素的相对降解量占5.5%~60.0%;烟筋类胡萝卜素相对降解量偏高,占5.5%~79.0%。凋萎期末,叶片及烟筋叶绿素相对降解量占88.0%~98.0%;叶片类胡萝卜素的相对降解量占9.0%~68.0%;烟筋类胡萝卜素相对降解量偏高,占12.0%~88.0%。结论]6个品种烤烟鲜烟叶叶片的叶绿素含量及不同品种不同部位的叶片叶绿素含量存在一定的差异。

Study on the Degradation of Chlorophyll in Lower Leaves of Flue-cured Tobacco during Curing Process

Objective ] The purpose was to study the change trend of chlorophyll in lower tobacco leaves during curing process. Method] The chlorophyll pigments and carotenoid were extracted by grinding with 80% acetone and their contents were determined by spectrophotometry so as to study the degradation of chlorophyll in lower tobacco leaves during curing process. Result] The chlorophyll content was highest in fresh lower tobacco leaves of Yun 203, secondary in that of PVH 19, lowest in that of Yun 97, and the carotenoid content was highest in that of PVH 19 and lowest in that of Zhongyan 100. In the end of yellowing stage, the relative degradation amount of chlorophyll in the leaves and tobacco veins accounted for more than 80.0% - 95.0%, that of carotenoid in tobacco leaves accounted for 5.5 % - 60.0 % and that of carotenoid was higher in tobacco veins, accounting for 5.5 % - 79.0%. In the end of languishing stage, the relative degradation amount of chlorophyll in the leaves and tobacco veins accounted for more than 88.0% -98.0%, that of carotenoid in tobacco leaves accounted for 9.0% -68.0%, and that of carotenoid was higher in tobacco veins, accounting for 12.0% -88.0%. Conclusion ] The chlorophyll content had some difference in fresh tobacco leaves of 6 varieties of flue-cured tobacco and in the leaves on different parts of different varieties.