The Effect On Yellowing Degree And Constant Temperature Spot At The Earlier Of Fixing Color For The Quality Of Flue-Cured Tobacco Variety C.V. CB-1

The experiments were carried out from year 2005 to year 2006 in the tobacco company of San Ming City in Fu Jian Province.The quality index determination and data analysis were completed in the Research Center of Tobacco and Health,University of Science and Technology of China and in the Laboratory of Digital Agriculture,Anhui agricultural University.Take the variety CB-1 as the material,the effect on yellowing degree of tobacco leaves at the last state of yellowing and constant temperature spot at the earlier stage of fixing color for outward quality,intrinsic chemical composition and fragrance quality were studied.Study result as follows:Ⅰ.The experiment on the yellowing degree of tobacco leaves at the last stage of yellowing.1 In the process of curing,the yellowing degree of tobacco leaves at the last stage of yellowing had certain effect on outward quality and main chemical composition of curedtobacco leaves.By "Yellow Vane and Blue Vein,Chief Vein Softening" process was the best to ensure the tobacco leaves outward quality and the coordination of chemical composition.2 The yellowing degree at the last stage of yellowing had an obvious effect on the aroma and taste component of cured-tobacco leaves.Firstly,with the enhance of yellowing degree the trend was obvious that the scent matter gross increasing firstly and falling subsequently. Among them,some components that were recognized had the distinct improvement function to the fragrance quality of cured-tobacco leaves,as,Isovalerate,Benzoic Acid, Phenylacetaldehyde,Furol,Dihydro-β-Violet Mellow,Solanone, Megasfigmatrienone(four isomers),Di-(2-ethylhexyl)Phthalate,Acetypyride,by "Yellow Vane and Blue Vein,Chief Vein Softening" process was highest,when further yellowing displayed reduced.Secondly,from classification of cured-tobacco leaves fragrance ingredients to look,the neutrality and acidity fragrance ingredients had a bigger contribution to the aroma and taste of cured-tobacco leaves,and the tendency that increasing first and falling subsequently was obvious with the enhance of yellowing degree,and the change of alkalinity fragrance ingredients was relative smaller.The carotenoid degradation product,the maillard reaction products,the phenylalamines degradation product were in the majority,and their changes are bigger,and the change of cembranenoides was not obvious.Thirdly,the change of the fragrance index of cured-tobacco leaves was obvious and had the tendency that increasing first and felling subsequently with the yellowing degree,the performance was H2＞H1＞H3,by H2 was highest.The A value reflecting the fragrance penetrability and mellowness had a obvious change with the yellowing degree,and the value was biggest by "Yellow Vane and Blue Vein,Chief Vein Softening" process.The B value reflecting the fragrance bottom rhyme was gradually increasing with the enhance of yellowing degree,but the difference displayed not remarkably.Ⅱ.The experiment on constant temperature spot at the earlier stage of fixing color.1 The different constant temperatures to outward appearance quality and the main chemical composition of cured-tobacco leaves had a different influence at the earlier stage of fixing color.Outward quality by 46℃and 48℃processes were better,the coordination of chemical composition was best by 44℃process.2 The influence on the constant temperature spot to the tobacco leaves fragrance characteristic was remarkable at the earlier stage of fixing color.Firstly,the fragrance matter total quantity was reduced with the elevating of the constant temperature,by 44℃process the fragrances matter total quantity was biggest,and the ingredients which had distinct improvement function to the fragrance quality of cured-tobacco leaves,as, Isovalerate,Benzoic Acid,Phenylacetaldehyde,Furol,Dihydro-β-Violet Mellow, Solanone,Damascone,Megasfigrnatrienone(four isomers),Di-(2-ethylhexyl)Phthalate, Acetypyride,by 44℃process was highest.Secondly,according classification of fragrance ingredient to look,the neutrality and acidity fragrance ingredients had a bigger contribution to the aroma and taste quality of cured-tobacco leaves,and the reduced tendency was obvious with the enhance of constant temperature,and the change of alkalinity fragrance ingredients was relative smaller.The carotenoid degradation product and the maillard reaction products were in the majority,and the changes were bigger.The changes of phenylalamines degradation product and cembranenoides were not obvious. Thirdly,the change of the fragrance index of cured-leaves was obvious and had the reduced tendency with the enhance of the constant temperature,the performance was K1＞K2＞K3,by K1 was highest;The A value reflecting the fragrance penetrability and mellowness had a obvious change with the different constant temperature,the value was biggest by 44℃process.The B value reflecting the fragrance bottom rhyme had the same tendency,but the difference displayed not remarkably.In summary,.this experiment indicated,by "Yellow Vane and Blue Vein,Chief Vein Softening" process at the last state of yellowing and by 44℃process at the earlier stage of fixing color were the best to ensure the quality of tobacco-cured to the variety c.v.CB-1 in San Min tobacco area.