Studies Of Inducing Aroma And Improving Tobacco Quality By Using Bacterial Strains

The main purpose of this study is to find out bacterial strains that are capable ofinducing aroma and improving tobacco quality. 8 strains were screened out. Aroma andflavor constituents analysis and enzyme mechanismof themwere determined. More than 865 isolates were isolated from samples of leafage collected from Yunnan,Shandong and Henan provinces. Based on analyzing of chemical, such as soluble sugar,total nitrogen, and nicotine, and referring to the quality standard of tobacco, 21 bacterialstrains were screened out. Based on analyzing of chemical and the panel test, 5 bacterial strains were screenedout. They were BT-30, BT-31, BH-27, BR-38 and BY-31. The panel test showed thatcompounds in tobacco became harmony. The results were between 74.6 and 75.9, andwere better than control class. BT-30 was 75.9 and increased 2.29%. The aroma qualityand aroma quantity increased 1.47% and 2.07% respectively, and offensive and irritancywere reduced. BH-27 and BY-31 had the same result. After B07, BT-30, BH-27, BR-38 and BY-31 treated the top, middle and lower K326tobacco leaves, the sugar/nitrogen and sugar/nicotine approached high quality tobacco andwere better than control class. Different bacterial strains that can improve the quality of the top, middle and lowertobacco leaves of K326 were BT-30, BH-27 and BY-31, BH-27 respectively. Different bacterial strains have different effect on tobacco leaves. The quality of thetop and lower tobacco leaves were better than middle tobacco leaves after they weretreated by bacterial strains. Changes of enzyme activities (including a-amylase, proteinase, peroxidase andcellulase) in fermented tobacco leaves were determined. Results showed that the values ofproteinase, peroxidase and cellulase activities of BH-27 were higher than control class,and the values of proteinase and peroxidase of BY-31 were higher than control class too,although enzyme activities were different in different time. And changes of chemicalsubstance have closely relativity with enzyme activities. The tested bacterial strains haveactivation to enzymes in fermented tobacco, and can convert and synthesize the aromaticcompounds in tobacco. This method was better than single enzyme.