烘烤过程水分调控对伏旱中部烟叶生化变化的影响  

Effects of Water Regulation during Curing on Biochemical Changes of Tobacco Middle Leaves under Summer Dry Condition

作　　者：王莲 孙红权 毛林昌 陈勇华 何文伟 艾复清 WANG Lian;SUN Hongquan;MAO Linchang;CHEN Yonghua;HE Wenwei;AI Fuqing(Tobacco College of Guizhou University,Guiyang,Guizhou 550025,China;Tongren Tobacco Company of Guizhou Province,Tongren,Guizhou 554300,China;Key Laboratory of Tobacco Quality Research of Guizhou Province,Guiyang,Guizhou 550025,China)

机构地区：[1]贵州大学烟草学院,贵阳550025 [2]贵州省烟草公司铜仁市公司,铜仁554300 [3]贵州省烟草品质研究重点实验室,贵阳550025

出　　处：《作物研究》2021年第3期232-236,共5页Crop Research

基　　金：贵州省烟草公司铜仁市公司科技项目。

摘　　要：为探讨烘烤过程中水分调控对伏旱烟叶生化指标的影响,通过设置烘烤变黄期不同湿球温度,分析伏旱条件下中部烟叶烘烤过程中主要生化指标的动态变化。结果表明:(1)随着干湿差逐渐加大,烟叶失水量在变黄期逐渐增加,而定色期和干筋期相应减少,但失水量最多的仍然是定色期,为46.5%~55.5%;叶绿素和类胡萝卜素的降解率与失水量变化呈相似趋势,但降解主要发生在变黄期,分别为89.0%~91.7%、58.0%~68.4%。(2)PPO酶活性的变化在烘烤过程呈双峰曲线,第1次峰值出现在变黄中期,第2次峰值出现在变黄后期且低于第1次峰值,2次峰值均呈现干湿差越小,峰值出现时间越晚、酶活性越低的特征。(3)MDA含量呈慢-快-慢的增加趋势,快速递增主要发生在变黄后期至定色前期;干湿差越小,MDA快速递增的时间越晚,递增速率越小,最终含量越低。综合分析,变黄期适当减小干湿差,有利于提高色素降解率、减少MDA含量、降低变黄后PPO酶活性,进而促进伏旱烟叶生理生化代谢,有效降低酶促棕色化反应的发生,有利于提高伏旱烟叶的烘烤质量。In order to explore the effect of moisture regulation on biochemical changes of tobacco leaves in drought summer during the curing process,the dynamic changes of the main biochemical indexes of the middle leaves under the conditions of summer drought were studied by setting different wet bulb temperatures during the yellowing period.The results showed that:(1)With the increase of the difference between dry and wet,the water loss of tobacco leaves increased gradually dur-ing the yellowing period,while decreased in the color fixing period and dry gluten period,but the most water loss was still in the color fixing period,which was 46.5%-55.5%;The degradation rate of chlorophyll and carotenoids showed a simi-lar trend to the change of water loss,but the degradation mainly occurred in the yellowing period,which was 89.0%-91.7%and 58.0%-68.4%,respectively.(2)The change of PPO enzyme activity during the baking process was a bi-modal curve.The first peak appeared in the middle stage of yellowing,the second peak appeared in the late yellowing stage and lower than the first peak,and the two peaks showed that the smaller the difference between dry and wet,the later the peak appeared and the lower the enzyme activity.(3)The MDA content showed a slow-fast-slow increasing trend,and the rapid increase mainly occurred from the late yellowing stage to the early stage of color fixing;the smaller the dry-wet difference,the later the time of rapid increase of MDA,and the smaller the increasing rate,the lower the final content.Comprehensive analysis showed that properly reducing the difference between dry and wet during the yellowing period was beneficial to increase the pigment degradation rate,reduce the MDA content and the PPO enzyme activity after yellowing,thus promote the physiological and biochemical metabolism of summer drought tobacco leaves,effectively reduce the oceur-rence of enzymatic browning reaction,and improve the curing quality of summer drought tobacco leaves.

关 键 词：烤烟 中部叶 伏旱 烘烤 生化指标 

分 类 号：S572.092[农业科学—烟草工业]