Studies On The Change Of The Main Physical Paramenters And Chemical Dynamics During The Tobacco Curing

In different varieties, and different parts of tobacco leaves of different maturity,including metabolism, transformation and accumulation of different degrees, accept the outside environment is different, so in the baking process, the length, width, thickness,moisture and other main chemical components have different patterns of change. Therefore,the study of dynamic changes of different varieties, different parts of the baking process, the main physical parameters of tobacco leaves of different maturity and the main chemical components, the main conclusions are as follows:1. The baking process, the leaf length, width, thickness and moisture content changes during yellowing, colour fixing stage, maximum stem drying stage and a small trend. In the baking 48h-84 h period, length, width, thickness and moisture changes most quickly. The three part leaf water loss rate of the average from 55.3% to 4.1%. The fastest time overripe leaf length and width, thickness and moisture changes slightly ahead of unripe and ripe tobacco leave. Upper leaves in 48h-84 h before baking, the length and width of the shrinkage rate from 2.8% to 9.8%, 5.9% to 14.7; 48-96 h middle leaf length and width shrinkage rate from 5.6% to 15.8%, 6.1% to 22.1%; the lower leaves increased from 4.9% to 17.1%, 9.4%to 24.9%. The length, width and thickness after curing shrinkage of upper leaves is significantly smaller than in the lower leaves, middle and lower tobacco leaves length and width shrinkage rate had no obvious difference.2. 36 h before baking, starch content decreased, 38-84 h velocity decreased slightly, after no obvious change. With the continuous decomposition of starch, total sugar content increased, 72 h before baking, the total sugar content increased significantly, especially in the first 36 h. Leaf NC55 content was significantly higher than that of other two varieties. There was no significant difference between the different parts of the starch content of Flue-cured tobacco. After baking the total sugar content between varieties were significantly different,the highest content of upper, middle and lowest. Tobacco leaves of different maturity of starch and total sugar content were significantly different, fresh leaves of unripe tobacco starch and total sugar were the highest, and lowest in mature leaves.3. The protein content change slowly, 48h-72 h changes during the fastest, then tends tobe gentle. Fresh tobacco and flue-cured tobacco leaf protein content of K326 was higher than that of other two varieties; content in upper leaves was higher than that in the lower part;immature than ripe than cooked. No significant difference in protein content among varieties of flue-cured tobacco; the upper part was significantly higher than that of the other two parts;overripe tobacco leaves was significantly less than that of unripe and ripe tobacco leaves.Less content of nicotine in tobacco leaves, in 2.0%-2.5%. With roasted continuously, the nicotine content decreased gradually, especially in the range of the maximum 36 h content before baking. The size of the nicotine content in baking: three varieties of tobacco NC55>K326> 100; among different parts of the upper > middle > lower; different maturity of unripe overripe ripe > >. 12 h before baking, a nicotine content variation of mature tobacco leaves was significantly greater than the other two maturity, from 2.51% to 2.42%; 24 h before baking, variation of nicotine content in lower leaf was significantly higher than the other two parts, from 2.41% to 2.21%.