Study On The Dynamic Changs Of Flue-Cured Tobacco Ageing And The Aging Time Of Different Areas

This article analyzed dynamic changes of physical characteristic, chemical component, aroma material, enzymatic activity and smoking quality of flue-cured tobacco from different areas during aging in He'nan. Results as follow: 1. Dynamic changes of physical characteristic of flue- cured tobacco from different areas during aging. Results showed that equilibrium moisture content waved with the change of humidity and temperature, and the filling powers were waving up, which were the higher about 9 and 21 months'tobacco aging of home, about 24 and 36 months'aging of abroad tobacco. Although Zimbabwe flue-cured tobacco aged 15 months ahead of home, the physical characteristics were not differential among them. 2. Dynamic changes of enzymic activity of flue-cured tobacco from different areas during aging. Results showed that PPO, POD, PAL, LOX and glycosidase changed unanimously. At the beginning of the aging process, enzymatic activity of these five kinds of enzyme tended to increased, and enzymatic activity reach their peak after six or nine months, then decreased gradually during domestic leaves aging. Each enzymic activity was descending slowly during Zimbabwe flue-cured tobacco leaves in 15-39 months'aging, which was relatively lower. 3. Dynamic changes of chemical components of flue-cured tobacco from different areas during aging. The contents of total sugar, total nitrogen and nicotine decreased slowly, and lower than the non-aging tobacco leaves during different aging stages, which tend to be coordinate. Organic acid contents also decreased gradually, which were good to the form of nice smoking quality. There were different of chemical components of different areas.4. Dynamic changes of aroma precusor components of flue-cured tobacco from different areas during aging. The contents of pigment, polyphenol and free amino acid descended during aging, and the extents were bigger in domestic tobacco, which were slow in Zimbabwe tobacco leaves. Petroleum ether extractive material contents were increasing gradually during premetaphase aging, then decreased little in later period, and the time was different when achieved the highest of different areas, and the Zimbabwe leaves delayed about 9-15 months compared with the domestic leaves. 5. Dynamic changes of neutral volatile flavor components of flue-cured tobacco from different areas during aging. Research showed that neoplytadiene contents were decreasing in a degree, while contents of products degraded by carotene, derivatives of phenylalanine, browning reaction products, products degraded by cembra-alkane increased during aging process. Total content of volatile aroma composition increased too. These results indicated tobacco leaves aging played an important role in improving aroma quality of tobacco leaves.6. Dynamic changes of smoking quality of flue-cured tobacco from different areas during aging. The results indicated that the changing rules of smoking quality were almost the same, presenting sensory-quality-last-rapid-upstroke-phase, best-quality-stable-phase and quality-descending-phase during aging. The best tobacco leaves aging time of Henan and Hunan was 21 months, suitable aging period was 18-24 months; the best time of Yunnan was 24 months, the suitable period was 21-27 months; the best time of Guizhou was 18 months, the suitable period was 15-21 months; the smoking quality of Zimbabwe during 15-45 months'aging was higher than the domestic tobacco quality, and the best time was 33 months, the suitable period was 30-39 months.