近年来,北方烟区降雨量明显增加.为保障气候变化下烟叶烘烤质量,本文以青岛烟区主栽品种NC55为试验材料,在产区成熟烘烤工艺基础上,设计了不同时段湿球温度组合(处理SD1,变黄阶段前期、中期、后期湿球温度分别为37、37、36～37℃,定色阶段前期、后期湿球温度分别为37、39℃,干筋阶段前期、后期湿球温度分别为40、41℃;处理SD2,变黄阶段前期、中期、后期湿球温度分别为38、38、37～38℃,定色阶段前期、后期湿球温度分别为38、40℃,干筋阶段前期、后期湿球温度分别为41、42℃),研究湿球温度对烤后烟叶经济性状、外观质量、主要化学成分以及感官质量的影响.结果表明,相较于处理SD2,处理SD1烤后烟外观质量总分提升了0.35分,均价提升了0.98元/kg,感官评吸质量提高了0.93分.综上,在青岛烟区降雨量增大的情况下,适当降低湿球温度能够提高青岛烟区烤后烟叶质量.

The physiology-biochemistry characters of step-temperature yellowing treatment were studied during bulk curing process by using the electric-heated flue-curing barn.The results showed that two obvious amylase activity peaks of step-temperature yellowing treatment appeared in yellowing stage and leaf drying stage,and amylase activity of step-temperature yellowing treatment was higher than 38℃ yellowing treatment.Polyphenol oxidase(PPO) activity of all the treatments decreased before 7-8 tenth yellow,then it displayed the trend with first increasing followed by decreasing after 7-8 tenth yellow for leaves during curing.And polyphenol oxidase activity of step-temperature yellowing treatment had a smaller variation range,and it was more relatively stable.chorophyll and carotinoid content of step-temperature yellowing treatment declined more than 38℃ Yellowing treatment.Starch of step-temperature yellowing treatment had a faster degradation,and its starch content was less than 38℃ Yellowing treatment during curing process.The step-temperature yellowing treatment was beneficial to increase the accumulation of total sugar and reducing sugar.The total nitrogen and nicotine contents of cured leaves of step-temperature yellowing treatment rose slightly,which was similar to 38℃ yellowing treatment.The step-temperature yellowing treatment was beneficial to improving the quality of tobacco leaf by the comprehensive performance of physiology-biochemistry.

Effects of different muscle-yellowing temperature on amylase activity,water content,the aroma constituents and smoking qualities of tobacco leaves during bulk curing were studied using the electric-heated flue-curing barn.The result showed that the amylase activity of all treatments had no difference during the yellowing stage.The amylase activity of different muscle-yellowing temperature treatment appeared as 48℃51℃45℃ during color fixing stage and stem-drying stage.Water content of all treatments had no difference during the early days of curing.After the end of the yellowing stage,the water content of 51℃ muscle-yellowing temperature treatment descend fastest.But the water content of 45℃ and 48℃ muscle-yellowing temperature treatment fall down slowly.Products of maillard reaction,products of phenylalanine,the content of solanone of 48℃ muscle-yellowing temperature treatment was highest.Total aroma constituents except neopytadiene of the 48℃ muscle-yellowing temperature treatment were also highest,51℃ muscle-yellowing temperature treatment took second place,and 45℃ muscle-yellowing temperature treatment was the lowest.Products of carotenoid,neopytadiene and total aroma constituents were highest in 45℃muscle-yellowing temperature treatment followed by 48℃muscle-yellowing temperature treatment.Smoking qualities of cured tobacco leaves was best in 48℃muscle-yellowing temperature treatment,which could improve tobacco fragrance quality and fragrance quantity,mask offensive odors,and improve after taste.

Flue-curing characteristics of flue-cured tobacco varieties Honghuadajinyuan,Zhongyan 100 and K326,which included changes of plastid pigments,water content and activities of polyphenol oxidase(PPO) were investigated,under the same curing conditions,in order to find out physiological and biochemical changes during curing process.The chemical compositions of cured leaves were measured and the appearances of economic characters were evaluated.The results showed that three tobacco varieties existed differences in yellowing process,water removal and activities of enzyme,Honghuadajinyuan performed slow loss of free water,high speed loss of bound water during fixing color stage,high ratio of free water and bound water,high activity of polyphenol oxidase,high chlorophyll content but low degradation,all these effected appearance quality after being cured;K326 performed rapid water loss during curing,low ratio of free water and bound water,polyphenol oxidase activity was at middle,the content of tobacco nicotine was high;the color change during the yellowing stage of Zhongyan100 was in accordance with water removal,with low PPO activity,low chlorophyll content,the percentage of fist-and middle tobacco leaves and average price were the highest.