The Effect Of Different Warehouse Conditions On Quality Of Aged Tobacco

Tobacco aging is an important method to improve the quality of tobacco.The changes of tobacco leave chemical substances are caused by chemical reactions,microbial effects and function of enzymes during aging.These mechanisms are affected by environmental temperature and humidity conditions,and then resulting in different aging rate and direction.Yunnan Province has the three-dimensional climate characteristics.The difference in temperature and humidity is significant in different areas.It provides a good base for the study on the law of change of tobacco during natural fermentation under different storage conditions.In this study,the warehouse of Yuanjiang,Mile,Chuxiong and Qujing of Yunnan province were selected as the aging warehouses of tobacco leaf.The selected varieties of tested tobacco are K326,Hongda,Yunyan 87,and the grade is WDC3F.During aging,the microorganism community changes in tobacco leaves were studied by cultivable method.The enzymatic activity of protease,amylase,catalase and polyphenol oxidase was measured by spectrophotometry.The changes of conventional chemical substances,polyphenol compounds and aroma substances in tobacco leaves were determined according to national standards.Base on the comparative analysis,the following conclusions were obtained:1.Yuanjiang warehouse showed annual high temperature and humidity;Mile warehouse had year-round rain and heat over the same period,high temperature and humidity;Chuxiong warehouse medium temperature and humidity,and it's climate change was obvious;while Qujing warehouse showed low temperature and humidity,and it's climate change was obvious too.2.Microbes on tobacco leaves are hardly affected by fermentative environmental microbes.Microorganism species and amount were more in the initial phase of ageing.Microorganism population structure changes,amount decreased and the bacteria gradually became a single with adding time.Bacillus bacteria become dominant species at a later stage.Rhizopus is the dominant species in fungus.3.The enzymatic activity of the protease on the tobacco leaves was higher with the aging.The activity of the other three enzymes was increased at begin and decreased at late stage,and processes synchronized with the bacterial population structure changes.When the number of bacteria increased,the enzyme activity also increased.It can be deduced that the production of enzymes was related to bacteria the presence of bacteria.4.In the process of aging,the nicotine content in tobacco leaves increased.The total amount of volatile organic acids and polyphenols decreased gradually,but the content of phenylacetic acid and scopolamine were increased.The total amount of incense ingredients has been rising.The variation range of chemical substances in different processes was different,which was consistent with the changes of bacteria and enzyme activity.5.In different aging warehouses,the changes of bacterial population structure,enzyme activity,chemical content are varied.The ambient temperature and humidity played an important role during aging processes.It showed that the flue-cured tobacco internal chemical composition change because of the changes of bacterial structure and enzyme activity were different under different temperature and humidity conditions during aging,so as to improve the quality of flue-cured tobacco.It provided important theoretical basis for tobacco leaf production and processing for tobacco industry.