Study On The Change Of Tobacco Quality In The Process Of Hainan Cigar Fermentation

Based on the fermentation process of Hainan Jianheng Havana Cigar Co.,Ltd.,this study conducted twice stacking fermentation test of wrapper and filler in the cigar planting base of Haiwei Town,Changjiang Li Autonomous County,Hainan Province in 2017.By analyzing the dynamic changes of physical characteristics,chemical components,aroma substances and TSNA during tobacco fermentation,the purpose is to understand the law of substance transformation and metabolism in the process of tobacco fermentation,and to clarify the positive role of secondary fermentation in improving the quality of cigar tobacco.At the same time,the macroscopic thermogravimetric analyzer was used to explore the changes of combustion characteristics of tobacco leaves during two fermentations.Combined with the correlation analysis of chemical components,the key influence factors affecting the combustion characteristics of tobacco leaves were explored.In order to provide scientific suggestions for the reasonable fermentation of Hainan cigar and theoretical basis for improving the availability of raw materials for cigar.The results are as follows:1.During the fermentation of Hainan cigar tobacco,the leaf weight and leaf thickness gradually decreased,the pulling force first increased and then decreased,reaching the maximum value at the second fermentation 20 days,and the equilibrium moisture content first decreased and then increased.The leaf weight and thickness of cigar filler were higher than those of cigar wrapper,and the pulling force,stem content and equilibrium moisture content of cigar wrapper were lower than those of cigar filler.The conventional chemical constituents of tobacco leaves generally decline during the fermentation process.Total nitrogen and nicotine decreased significantly during the second fermentation period.The Sugar-alkali ratio and Sugar-alkali ratio of tobacco leaves were stable in the fermentation process,but generally low.High nicotine is one of the main characteristics of Hainan cigar.Reducing nicotine needs to be the focus of production and management in the future.2.During the fermentation of Hainan cigar tobacco,the total amount of nonvolatile organic acids increased first and then decreased,and the accumulation rate increased significantly in the initial stage of secondary fermentation.The content of higher saturated fatty acids was at a low level,and the content of higher unsaturated fatty acids decreased gradually with the fermentation.Lutein and β-carotene showed a continuous decline during the fermentation process,and the rate of decline in the secondary fermentation period was significantly accelerated.The content of free amino acids showed a trend of increasing first and then decreasing.The "inflection point" of the change occurred in a fermentation for 20 days.The change of proline was special,and it showed an upward trend during the fermentation process;the change rule of glycine was not obvious.3.During the fermentation process of Hainan cigars,the total amount of neutral aroma substances(except neophytadiene)showed a trend of increasing first and then decreasing,but the change trend of cigar wrapper and cigar filler was not the same.The total amount of neutral aroma substances began to decrease at 10d and 20d respectively.Secondary fermentation can further promote the accumulation of aroma substances in the initial stage,but with the progress of fermentation,there will be some loss of aroma substances in the later stage.Especially for cigar wrapper,the second fermentation time should not be too long to avoid the decline of aroma quality of tobacco leaves.4.The free ammonia and free nicotine of Hainan cigars showed a decreasing trend during the fermentation process,and the decrease was more obvious in the secondary fermentation.Cigar free ammonia and free nicotine reached significant differences in each period of secondary fermentation.The proportion of alkaloids in cigars in Hainan is basically nicotine>neonicotinoid>nornicotine>pseudo-ergosine,of which nicotine accounts for about 85%of the total alkaloids,which is more obvious during the fermentation process;And the content of neonicotinoids decreased slowly with the progress of fermentation;the content of pseudo-euryrine did not change much and was stable.The proportion of each component of Hainan cigar TSNAs is basically NAT>NNN>NNK>NAB.As the fermentation progressed,the TSNAs of cigar tobacco leaves increased significantly.5.Comparing combustion curve images,secondary fermentation can significantly increase the maximum weight loss rate of cigar leaves,but has no positive effect on reducing the ignition point and burnout temperature.The ignition point and burnout temperature of tobacco leaves after primary fermentation were lower.The combustion zone moves to the low temperature zone.Potassium-chlorine ratio is the key factor to determine the ignition point and burnout temperature of cigar smoke,while total nitrogen and nicotine content are the main limiting factors for the maximum weight loss rate of tobacco leaves.6.The results show that the secondary fermentation can further promote the accumulation of organic acids and neutral aroma substances in cigars and improve the aroma quality of tobacco leaves on the basis of one fermentation,but the aroma substances will also decrease with the progress of secondary fermentation.Therefore,it is necessary to strictly control the secondary fermentation cycle to avoid the loss of aroma substances.At the same time,the secondary fermentation has a significant effect on reducing the volatile alkali of tobacco leaves.During the secondary fermentation process,the cigar smoke irritation is gradually reduced,the ammonia smell is eliminated,and the cigar characteristic aroma is more exposed.In addition,secondary fermentation can significantly increase the maximum weight loss rate of cigars,and the aroma substances are fully released during the combustion of tobacco leaves.Accumulation fermention can improve the quality of cigar tobacco,but also increase the TSNAs content of tobacco leaves.Therefore,in the future production,it is necessary to pay attention to optimizing the fermentation process to improve the safety of tobacco leaves.