Study On The Main Biochemical Changes During Flue-curing Of Three Methods Of Tobacco Curing

In order to study the changes of the main physiological and biochemical indexes of Yunyan87 during the flue-curing process in different cruing ways.The changes of water content,the change rule of dry matter,the change rule of main enzyme activity and the change rule of main chemical components of Yunyan 87 based on the conventional hanging curing,"two stew one stop" and loose Leaf curing,the curing process of three intensive curing methods.The main research results are shows:1.In the process of curing,the water loss rate of tobacco leaves showed a trend of fast-slow-fast-slow.In the same way of curing,the water loss rate showed that the upper leaves were larger than the middle leaves.For the different curing methods,the water loss rate loss rate of tobacco leaves showed loose Leaf baking(T3)> conventional baking(T1)> " two stew one stop"(T2)during the early of yellowing,the latter is just the opposite.After the end of yellowing,the moisture content of T2(" two stew one stop")treated water and environmental humidity is higher than that of the other two treatments,which is conducive to prolonging the physiological and biochemical changes in tobacco leaves for a long time.2.In the whole tobacco curing process,the loss rate of dry matter was all shown as: " two stew one stop " > conventional curing > loose Leaf curing.The loss rates were 22.85%,20.7%,18.08%,21.13%,19.27% and 17.36% respectively.As the " two stew one stop " curing is long time consuming,and the physiological and biochemical time is prolonged,more energy is needed to provide material metabolism,and resulted in the loss rate of dry matter rise,the maximum amount of dry matter loss.The amount of dry matter decreased after curing were " two stew one stop" curing > conventional curing > loose Leaf curing,and T2("two stew one stop " curing)is more conducive to the transformation of dry matter.3.The activity of protease and amylase in the tobacco curing process was similar,and all showed the "Tow-peak curve",which was rise-drop-rise-drop.However,there were certain differences in the activity of two kinds of enzymes in different curing methods,and the activity of T2 treatment("two stew one stop" curing)was the highest.There was also a certain difference in the time of the peak activity of the two enzymes in different curing methods.The peak value of protease and amylase in T2("two stew one stop")treatment was 42 h,78h,42 h and 84 h respectively,compared with other treatment late 6h-12 h,this indicates that the activity of T2("two stew one stop")treatment enzyme lasts longer.The content of protein and starch decreased rapidly during the curing process of the yellowing period,but the decrease rate was T3 > T1 > T2 at the early stage of yellowing,and T2 > T1 > T3 at the later stage of yellowing.It was stable around 90 h and the content of starch and protein was the lowest in the final T2 treatment,and the change of total sugar and reducing sugar content was the opposite.Therefore,"two stew one stop" intensive curing is the most beneficial to improve the activity of protease and amylase in tobacco leaves,which is the most beneficial to the decomposition of starch and protein.4.There are similar changes in the activities of CAT,POD,and T-SOD during tobacco curing,both show a parabolic change law that increases first and then decreases.There was also a certain difference in the time of the peak activity of the two enzymes in different baking methods,the activity of CAT and T-SOD are both shown as " two stew one stop" curing > conventional curing > loose leaf curing.The peak time of CAT was in 48 h,42h and 36 h,respectively.T2 peak time processing occurs 6-12 h later than T1 and T3,and the middle leaves > upper leaves.The peak time of T-SOD was in 42 h,36h,30,respectively.T2 peak time processing occurs 6-12 h later than T1 and T3,and POD activity is changed to be loose leaf curing > conventional curing > " two stew one stop " curing,the peak time was at 36 h,42h.T2 peak time processing occurs 6h later than T1 and T3,and the upper leaves > middle leaves.5.The change regularity of total nitrogen and nicotine in tobacco leaves was not obvious during the curing process.The content of K and petroleum ether extract both show variations in volatility.After curing,the content of each substance is slightly greater than the time of harvest,which showing an increasing trend...