以烤烟 K326为材料，对比分析堆积变黄和烘烤变黄过程中烟叶变黄速率和主要化学成分的动态变化规律。结果表明，与烘烤变黄相比，堆积变黄处理的烟叶变黄速率较低，色素降解慢；烟叶烘烤处理72 h，有超过90％的烟叶达到8～9成黄，而堆积变黄处理仅有44％的烟叶达到8～9成黄；在堆积变黄过程中，以总糖和还原糖为主的碳水化合物变化最为明显，其含量随变黄时间的延长而逐渐上升；初烤烟叶中，堆积变黄的烟叶总糖、还原糖、烟碱、总氮含量均明显高于烘烤变黄的烟叶，而其钾和氯含量均不同程度低于烘烤变黄的烟叶。

Three tobacco-loading patterns were tested in the bulk curing barn to study the effect of different tobacco-loading patterns on quality of organic tobacco.The results showed that the tobacco-loading patterns of the disperse leaves-sticking and leaves-loading with a clip could accelerate tobacco yellowing degree compared with the tobacco-loading with a rope pattern and the tobacco quality with deep color,sufficient oil content,lower nicotine content,lower protein content and better harmony of main chemical components under the disperse leaves-sticking pattern was the best,followed by the leaves-loading with a clip.

In order to explore the optimum process conditions and modes,taking middle leaves of cultivar Bina 1 as material,effects of different temperature and humidity conditions on the physical characteristics and economic characters of flue-cured tobacco leaves during loose leaf bulk curing were studied.The results showed that T1 treatment (dry bulb and wet bulb temperature were 36℃ and 32℃ in the leaf yellowing stage respectively;meanwhile,dry bulb and wet bulb temperature were 50℃ and 35℃in the leaf drying stage respectively)and T5 treatment (dry bulb and wet bulb temperature were 38℃ and 36℃ in the leaf yellowing stage respectively;meanwhile,dry bulb and wet bulb temperature were 50℃and 37℃ in the leaf drying stage respectively)had a better appearance quality,a higher average price and output value.Appearance quality standard scores of T1 and T5 were 83.20 and 83.50,average price were (19.5±1.09)Yuan and (19.80±1.22)Yuan,output value per 667m2 were (3 892.33±98.02)Yuan and (3 737.57±10.71)Yuan,respectively.

The differences of neutral aroma(including carotenoid degradation products, aromatic amino acids, cembranoids and neophytadiene et al.) content of 4 different genotypes of flue-cured tobacco leaves in Guizhou were studied by GC-MS method. The result showed that Bina1, Guiyan1 and Guiyan2 had higher neutral aroma than that of K326. The total neutral aroma, carotenoid degradation products, aromatic amino acids, cembranoids and neophytadiene content of Bina1 were higher than others. The carotenoid degradation products content of Binal was significantly higher than Guiyan2, and neophytadiene content was significantly higher than K326. Guiyan1 and Guiyan2 had higher neutral aroma content than that of K326, just because of their higher neophytadiene content.

研究不同采收成熟度对贵州有机烟叶中性致香物质含量的影响.结果表明,在尚熟到完熟的成熟度等级中,中部有机烟叶的中性致香物质含量随成熟度的增加先大幅度下降再缓慢上升,在尚熟时达到最大值;上部有机烟叶的中性致香物质含量随成熟度的增加先缓慢上升再缓慢下降,在成熟时达到最大值.中部有机烟叶的新植二烯、类胡萝卜素类降解产物、棕色化反应产物和类西柏烷类降解产物类致香物质含量的变化趋势与中部有机烟叶中性致香物质含量变化一致;上部有机烟叶的新植二烯、棕色化反应产物和类西柏烷类降解产物类致香物质含量的变化趋势与上部有机烟叶中性致香物质含量变化一致.中部有机烟叶在尚熟时采收,上部叶在成熟时采收香气物质总量最大.

以烤烟品种K326为材料，分析散叶密集烘烤过程中不同成熟度（尚熟、成熟、完熟）下部烟叶中几种抗氧化酶活性和丙二醛的动态变化趋势，并统计初烤烟叶的经济性状指标差异情况，研究密集烤房中成熟度对下部烟叶抗氧化酶（ POD、SOD、CAT）、丙二醛（ MDA）及烤后烟叶经济性状的影响，为进一步优化散叶烘烤工艺和提高烟叶烘烤质量提供参考。结果表明：在变黄期，MDA含量随着烘烤进程缓慢上升，不同成熟度烟叶间差异不大；MDA含量在定色前期（72 h）迅速上升后下降，表现为完熟烟叶＞成熟烟叶＞尚熟烟叶。不同成熟度下部烟叶抗氧化酶（ POD、SOD、CAT）活性高峰期基本上均在变黄中期（24 h）至定色前期（72 h），在烘烤72 h之后迅速降低。整体而言，密集烘烤中下部烟叶抗氧化酶活性表现为完熟烟叶＞成熟烟叶＞尚熟烟叶，成熟烟叶中的酶活性变化较完熟烟叶更为剧烈。从经济性状指标上看，成熟烟叶烤后经济性状优于尚熟和完熟烟叶，佐证了成熟度因素在烟叶品质形成中的重要性。研究表明，为了获得较为优质的烟叶，散叶烘烤下部烟叶适宜的成熟度应为成熟至完熟。

为进一步提高烤烟烘烤质量，改善烟叶香气品质，研究烤烟挂竿密集（T1）、烟夹装烟（T2）、散叶插扦（T3）烤后烟叶中性和酸性香气物质含量的差异。结果显示，T3处理中性香气成分总量（407．412μg/g）及类胡萝卜素降解产物、美拉德产物（棕色化反应产物）、芳香族氨基酸（苯丙氨酸类）、西柏烷类和新植二烯等5类中性香气成分含量均最高，其次是T2，T1处理最低。酸性香气成分含量以T2处理（468．275μg/g）最高，T1处理（359．445μg/g）最低。

The aroma constituents were tested by using four types of tobacco loading,including common loading leaf with pole,loose-leaf accumulation,sticking tobacco leaves and loading leaf with clip,in order to investigate the relationship of different loading method and aroma constituents of tobacco leaves in bulk curing barn.Results:1) The content sequence of neutral aroma constituents was loose-leaf>sticking>pole>clip,compared with common loading leaf with pole,the neutral aroma constituents of loose-leaf accumulation and sticking tobacco leaves were increased by 10.94% and 8.48% respectively.2) Loose-leaf accumulation increased the contents of degraded carotenoid products,maillard reaction products,phenylalanine products,cembratriendiol products and neophytadiene,sticking tobacco leaves increased the contents of degraded carotenoid products and neophytadiene by 8.54%,12.16% respectively;clip increased the contents of phenylalanine products(benzal dehyde,benzal alcohol,phenyl acetaldehyde and phyenyl ethylalcohol).In general,the aroma constituents were increased in loading of loose-leaf accumulation and sticking tobacco leaves,the aroma constituents of tobacco leave had a close affinity to loading method.

概述了烤烟烘烤加热方式的研究现状,介绍了远红外加热技术的特点及工作原理,展望了烤烟烘烤加热方式的发展趋势.

In order to improve the appearance and grade quality and internal quality of flue-cured tobacco leaves,especial for aroma quality.The effect of different harvest maturity(immature,ripe and overripe) on appearance and grade quality,routine chemical components,sensory evaluation and aroma quality of flue-cured leaves were studied.The results showed that ripe(M2) treatment had a better appearance quality grades(average price,high class leaf,orange tobacco rate),had a higher content of the neutral aroma except for neophytadiene.M2(ripe) treatment also had the highest content of the ten kinds of components in twelve acidity aroma component.Routine chemical components and sensory evaluation of the M2 and M3 treatment was better.Aroma quality,aroma volume and taste etc of tobacco leaves were improved following with increasing of the ripeness degree.Ripe harvest is basement for gaining better appearance quality grades of tobacco leaves.Overripe harvest could improve internal quality of flue-cured tobacco leaves,but it could increase the variegation proportion of flue-cured tobacco,and reduced the tobacco appearance and grade quality.

[Objective]The research aimed to study the effects of temperature in bulk curing barn and air-pressure of artificial humidification on conditioning of cured leaf tobacco.[Method]The cured leaf tobacco were artificially humidified with conditioning plant before unloading from bulk curing bark in the test.[Result]The results showed that the preferential temperature for humidification-conditioning of leaf tobacco was 50-55 ℃ in barn,and spray air-pressure should be kept within 3-4 atmospheric pressure about 60-90 min.For fear of excessive conditioning and secondary dehydration in practice,operation of humidification-conditioning had to be ceased when the moisture content of cured leaf tobacco in barn was up to 12%-13% and partial leaf tobacco felt humid by touch,and leaf tobacco should be unloaded in 10-20 min after that.[Conclusion]This research determined the best way and procedure of artificial humidification of cured leaf tobacco.

Effect of 3 fresh tobacco loading densities(55～60,60～65,and 65～70kg/m2 from low to high density) on tobacco leaves' quality and energy consumption were studied in the bulk curing barn to explore the most suitable loading density of tobacco by loose-leaf stacking.The results showed that compared with low density both mid to high density of loading density,especially mid density could improve the economic character of tobacco,harmonize the chemical composition,and improve the quality of tobacco leaves.Increasing the loading density could reduce the energy consumption cost,total cost of mid density reduced by more than 8%,and high density reduced by more than 14% compared with low density.In conclusion,the fresh tobacco leaves loading density of 60～65kg/m2 could be optimum in bulk curing barn by loose-leaf stacking.

Five different loading tobacco leaf patterns were tested in the intensive curing barn to study the effect of different loading pattern on tobacco quality.The results showed that the tobacco economic character from the intensive curing barn was significantly higher than that from the common curing barn,curing in the intensive curing barn could increase total sugar content of tobacco leaf and reduce total nitrogen content in tobacco leaf,and the loose-leaf stack loading pattern,tobacco clip loading pattern and loose-leaf stack with a frame loading pattern in the intensive curing barn could effectively improve tobacco quality,and the best tobacco quality was from the loose-leaf stack with a frame loading pattern.

In order to investigate the measures of saving labor force and energy during the development of tobacco agricultural modernization,the experiment of loading tobacco leaf was conducted with four treatments(traditional loading leaf with pole,loose-leaf accumulation,loose-leaf with frame,and loading leaf with clip).The results showed that three methods of loading leaf(loose-leaf accumulation,loose-leaf with frame,and loading leaf with clip) decreased significantly the cost of labor force and energy during curing when compared with the method of traditional loading leaf.The cost of labor force of loading and unloading leaf,coal,and electricity decreased respectively over 70%,18%,and 10%.In addition,the difference of the economic characters,appearance qualities and contents of chemical components of curing leaves between different treatments was inconspicuous.

The experiment was conducted to study the effect of different wet bulb temperature at the color fixing stage on tobacco quality under loose-leaf and bulk curing condition.The results showed that the single leaf weight and external quality of cured tobacco under 34℃ to 36℃ temperature at the color fixing stage was highest,and the ratio among chemical components and smoking quality of cured tobacco under 36℃ to 38℃ temperature at the color fixing stage was the best.The optimum wet bulb temperature at the early color fixing stage and main color fixing stage was 34℃ to 35℃and 35℃ to 37℃ under loose-leaf and bulk curing condition respectively.

The change pattern of appearance characteristics and chemical components of tobacco leaves were studied during the loose-leaf bulk curing process. The results indicated that the difference of loading method of tobacco leaves between the loose-leaf bulk curing barn and the hang-pole curing barn resulted in the different appearance of tobacco leaves and conditions of temperature and humidity in the curing process. the faster speed of water-losing at the late-stage of yellowing and the slower speed of water-losing in the color-fixing period in the loose-leaf bulk curing barn than in the hang-pole curing barn were the major characteristics which affected the formation of tobacco leaves quality. Application of the curing method of pre-decreased less humidity and appropriately lengthened the time of the color-fixing period, could effectively resolve the problem of tobacco leaves quality caused by the high temperature and humidity. In addition, the change of chemical components of tobacco leaves during the loose-leaf bulk curing was the same with the hang-pole curing.

In the process of traditional tobacco planting,the working procedure was complicated and it needed a great deal of labor force.In order to promoting the transformation of traditional tobacco agriculture to modern tobacco agriculture,some planting ways of saving labor force of flue-cured tobacco in Guizhou province were introduced.