Study On Chemical Basis Of Tobacco Leaves Color Changes During The Aging Treatment

In this study,36months aging treatment of Zhongyan100, K326, Yunyan85, ZC-01in ShandongZhucheng Aging Treatment Library was used, to comparative analysis of the different status of tobaccocolor, determining the method of tobacco color quantification measurement; for the first time usingcolor difference meter for quantitative measurement of color during the aging process, and dynamicchanges the chemical components and sensory quality, to investigate the chemical basis of tobacco colorchange during aging process, and provide a theoretical basis for the Shandong tobacco leafalcoholization. The main results were as follows:(1) Methods of quantitative measurement of leaf color. Application of color difference meter whichhas high precision, the tobacco leaves were ground into powder and mixed to measured, the L*, a*/b*,C*value as a measure of tobacco color index, can not only to show the leaf surface of tobacco leaf, butalso can be used to compare the differences among different leaf color.(2) During the aging process of appearance quality and internal quality changes occurred mainly inthe period of0-18months, the leaf surface dark, dim, saturation was more uniform, and the chemicalcomponents was further degradation, aroma quality, aroma quantity increased, the aftertaste of alcohol,smoking total scores increased. With the aging treatment，leaf color and internal quality tends to bestable.Zhongyan100reducing sugar and total sugar content, total alkaloid and total nitrogen contentwas low, high content of polyphenols and carotenoids content was low, at the same time, highest droprang of polyphenols and carotenoids, resulting in compared with the other three varieties, the a*/b*value of Zhongyan100reduced earlier, and the maximum E before and after aging. K326sensoryindexes reached the lowest in24months, which was later than the other three varieties.Shandongflue-cured tobacco optimum aging time was18months. Zhongyan100alcoholization ability was low,and need to reduce the aging time according to the actual situation, the aging time of the K326can beincreased to24months.(3) Leaf color parameters L*and total sugar, reducing sugar, polyphenols and carotenoids showedsignificant positive correlation, and the total alkaloid was a significant negative correlation, correlationwith total nitrogen did not reach significant level. The value of a*/b*and total sugar, reducing sugar,polyphenols and carotenoids were significantly or very significantly negative correlation, total alkaloidssignificantly positive correlation, but the correlation with the total nitrogen did not reach significantlevel. The correlation between C*and total alkaloid, lutein was significant positive correlation. Throughmultivariate statistical analysis and principal component analysis showed that the effected chemicalsubstances of tobacco color during the aging process can be divided into sugar and total nitrogen,polyphenols, carotenoids and total alkaloid.(4) The Leaf color parameters and tobacco sensory smoking values were basically reached asignificant level, indicating that the change of tobacco leaves color parameters during tobacco agingtreatment can reflect the tobacco sensory evaluation indexes. The stepwisere gression equation shows that aroma, aftertaste, gas and tobacco color parameter correlation.