密集烘烤定色期烟叶类胡萝卜素降解及相关酶活性变化  

The Degradation Mechanism of Carotenoids in Flue-Cured Tobacco and the Changes of the Related Enzymes Activities at Leaf-Drying Stage During the Bulk Curing Process

作　　者：宋朝鹏[1,2] 高远[2] 武圣江[2] 许自成[2] 宫长荣[2] 张卫建[1] 

机构地区：[1]南京农业大学农学院,南京210095 [2]河南农业大学烟草学院,郑州450002

出　　处：《中国农业科学》2009年第8期2875-2881,共7页Scientia Agricultura Sinica

基　　金：国家烟草专卖局资助项目(3300806156)

摘　　要：【目的】研究密集烘烤定色阶段烤烟类胡萝卜素降解及相关酶活性的变化,为密集烤房烘烤工艺优化和完善提供理论依据。【方法】采用河南农业大学设计的电热式温湿自控密集烤烟箱,按照低温中湿变黄、中湿定色烘烤工艺,对比研究定色期不同升温速度对类胡萝卜素各组分含量变化及相关酶活性的影响。【结果】类胡萝卜素含量随烘烤过程推进逐渐降低,慢速升温烘烤(T1)类胡萝卜素各组分(β-胡萝卜素、叶黄素、新黄质、紫黄质)降解量相对较大,比快速升温烘烤(T2)分别高10%、2%、32%和32%,但处理间差异不显著(P>0.05)。烘烤条件对酶活性影响显著,并且脂氧合酶(LOX)、苯丙氨酸解氨酶(PAL)、多酚氧化酶(PPO)、过氧化物酶(POD)对烟叶烘烤质量的影响是双向的,定色前期相对较高的酶活性有利于生成更多的香气前体物质。【结论】慢速升温定色能很好地调控各种酶活性的变化,使细胞氧化还原反应达到一种动态平衡,使类胡萝卜素充分降解,又能避免酶促棕色化反应的发生,为进一步改善烟叶品质和优化密集烤房增香工艺提供参考。[ Objective ] The degradation mechanism of carotenoids and the changes of related enzymes activities in flue-cured tobacco at leaf-drying stage during the bulk-curing process were studied in order to provide a theoretical basis for optimization and perfection of curing technology. [Method] The effect of different rising speeds of temperature on the degradation ofcarotenoids and the related enzymes activities at the color-fixing stage during the bulk curing process was studied by using the electric-heated flue-curing barn designed and made by He＇nan Agricultural University on the basis of curing technology with yellowing at low temperature middle humidity and leaf drying at middle humidity. [ Result] The results showed that the contents of carotenoids decreased gradually at color-fixing stage during the bulk curing process; the degradation contents of carotenoids components （β-carotene, lutein, neoxanthin, violaxthin） of the slow heating curing （T1） was relatively large and was higher than the rapid heating curing （T2） by 10 %, 2 %, 32 % and 32 %, respectively, but there were no differences among treatments （P〉0.05）. Effect of different conditions of curing on the activities of enzymes were significant and lipoxygenase, phenylalanine ammonialyase, peroxidase and polyphenol oxidase had a bidirectional effect on the quality of tobacco leaves. It was beneficial to form more premise matter of aroma based on the higher enzymes activities at early leaf-drying stage. [Conclusion] The slow heating could regulate the change of various enzymes activities reasonably, make cell redox reaction reach to dynamic balance and make the degradation of carotenoids adequately. Meanwhile it could avoid the occurrence of browning reaction and provide a reference for improving the quality of tobacco and optimizing technology of bulk curing and aroma-enhancing further.

关 键 词：密集烘烤 定色期 类胡萝卜素 降解机理 酶 

分 类 号：S572[农业科学—烟草工业]