Study On Extraction Of Tobacco Stem And Improvement Of Its Nature By Biological Methods

In this study, tobacco stem as raw material was hyrolyzed with exogenous enzymes toobtain its extract. Fermentation with Aroma-producing microorganism and Maillard reaction wasused to improve its flavor and the optimal processing parameters was studied to enhance thequality of tobacco stem extract which could be applied for reconstituted tobacco. The maincontents are as follows:1) Tobacco stem was hydrolyzed with exogenous enzymes to obtain its extract. Afterscreening three enzymes, complex cellulase, thermostable amylase and glycosidase GAⅡshowed the most desirable hydrolysis effect. Single enzyme and combination of the threeenzymes were studied to hydrolyze tobacco stem and the results showed that the optimal addingarrange of complex cellulase, thermostable amylase and glycosidase GA II were1.3%-3.8%,1.2%-2.7%,1.2%-2.3%, respectively. Through combination experiment of three enzymes, theoptimal composited ratio enzymes is1.70:1.12:1.00.2) The optimal processing condition was studied with the compound enzyme to hydrolyzethe tobacco stem. The results showed that the concentration of tobacco stem is10%, the optimalpH of the reaction is5.0, the amount of enzymes is2.5%, the optimal temperature is50℃, therotational spreed of the water-bath shaker is150r/min, the optimal reaction time is10hours.Under this processing condition, the reducing sugar improved158.7%.3) Each of Aroma-producing Yeast, Lactobacillus debrueckii and Bacillus subtilis and theircombination were studied to improve the quality of tobacoo stem extract. The results showed thatthe aroma, smoke, taste of the extract were improved at different levels after being treated withmicroorganisms, and the best qualify of extract was obtained after being treated withAroma-producing Yeast&Lactobacillus debrueckii. The optimal fermentation condition wasfurther studied.4) After tobacco stem was treated with enzymes, microorganism fermentation and Maillardreaction, the changes of the reducing sugar, amino acid and vaporing aroma in the extract werestudied. Compared to the traditional three-step reverse flow extract processing, An efficientprocessing route was determined to improve the quality of tobacco stem extract, which couldincrease reducing sugar by3.9%, amino nitrogen by54%, volatile components by239.6%.