卷烟、雪茄烟生产、购进销售；烟叶、烟丝、复烤烟叶购进销售；卷烟纸、滤嘴棒、烟用丝束购进销售；烟草专用机械购进销售；联营加工所需烟草专卖品供应；卷烟、雪茄烟出口；烟叶、复烤烟叶、烟丝、卷烟纸、滤嘴棒、烟用丝束、烟草专用机械出口（限有投资或合作项目的境外烟草企业）；与烟草制品生产销售相关的其他生产经营，多元化经营、职工培训、技术开发与服务、资产经营管理等。
The effects of different pore sizes nanofiltration membrane on the volatile components and contents of Cymbopogon citratus extract were analyzed,which provided a technical reference for the preparation of natural flavors in Cymbopogon citratus.Five levels of nanofiltration membranes with different pore sizes of 10 kDa,1 kDa,500 Da,300 Da,and 200 Da were used for fine separation of Cymbopogon citratus extract,and gas chromatography-mass spectrometry(GC-MS)was used to analyze the volatile components in the filtrates separated by five kinds of nanofiltration membranes with different pore sizes.The odor activity value(OAV)was calculated and the cluster analysis was carried out.The results showed that a total of 56 volatile components were detected in Cymbopogon citratus extract,and the aroma types of the filtrates separated by different nanofiltration membranes were basically similar.With the decrease of the nanofiltration membrane pore size,the relative content of hydrocarbons,acids and ketones in filtrate decreased,while the relative content of alcohols and aldehydes increased,and the total content of compounds decreased gradually.The content of the same volatile component decreases with the decrease of the pore size of the nanofiltration membrane.By OAV analysis,18 compounds such as(+)-citronellal,geraniol and citronellol were found to be the key contributors to the characteristic flavor of Cymbopogon citratus extract.The results of sensory similarity evaluation showed that the aroma types of the filtrates separated by different nanofiltration membranes were basically similar and difficult to be distinguished.However,the smaller the pore size of the nanofiltration membrane was,the higher the sensory identification of the filtrate was,and the easier it was to be distinguished.Nanofiltration membrane could effectively reduce the complexity of the flavor substance system of Cymbopogon citratus extract.It was hoped that the research could provide technical support and theoretical reference for the development of stable and practical Cymbopogon citratus essence products.
In order to increase the content of ester compounds in fermented tobacco extract,using tobacco extract as fermentation substrate and Sac-charomyces cerevisiae SMR-SC-11 as fermentation strain,the fermentation conditions were optimized by single factor and response surface test with ester contents as evaluation index,and the physicochemical indexes of tobacco extract were analyzed before and after fermentation.The results showed that the optimal fermentation conditions were:fermentation time 111 h,temperatuire 32 ℃,inoculum 5％,initial pH 6.7.Under the optimized conditions,the ester compounds yield was 2.28 g/L,and the ester compounds contents in tobacco extract after fermentation was increased by 714.28％compared with that before fermentation.The contents of protein,total sugar,reducing sugar and amino acid nitrogen was decreased by 26.7％,23.6％,33.0％and 58.3％,respectively,while the contents of Na+and K+had no significant change.
