How to treat tobacco leaves?

As the agricultural proverb says, "A good barbecue is a treasure, and a bad barbecue is a pile of grass". In the actual baking process, you need to pay attention to the following points:

1. Normal tobacco curing. ① Yellowing stage. Close skylights, underground holes, doors and windows after loading cigarettes. After several hours of pre-yellowing, the dry bulb temperature rose to 36℃ ~ 38℃ at the speed of 65438 0℃/hour, the wet bulb temperature was controlled at 35℃ ~ 36℃, the difference between wet and dry was kept at 65438 0℃ ~ 2℃, and the temperature stabilized for a long time, which made the bottom tobacco leaves yellow and soft before 42℃. At the end of yellowing, the yellowing degree of the lower leaves should reach 80%; The middle and upper leaves turn yellow to 90% to 10%, the leaves wither and the main veins begin to soften and curl. ② Fixing stage. After yellowing meets the requirements, the dry bulb temperature rises to 54℃ within 2 ~ 3 hours. If the tobacco leaves lose water slowly or the stems turn yellow slowly, it must be kept at 45℃ ~ 48℃ for a long time to make the stems turn yellow. After some tobacco leaves are rolled into small rolls, the temperature is raised to 54℃ ~ 55℃ at the speed of 1℃~ 2℃/ hour, and the temperature is stabilized until the tobacco leaves are completely dried. With the increase of dry-bulb temperature, the wet-bulb temperature rises synchronously and keeps at 38℃ ~ 40℃. At this stage, the change requirements of tobacco leaves are: before 50℃, the middle and upper layers of tobacco leaves are fully yellow and soft, reaching yellow flakes and yellow tendons, and the temperature is stable at 54℃ until the tobacco leaves bulge. ③ Dry strengthening stage. At the speed of 65438 0.0℃/hour, the temperature was raised from 55℃ to 68℃, and the maximum temperature was not more than 70℃ until the tobacco leaves were completely dried. The temperature of wet bulb is stable at 40℃ ~ 42℃ until the baking is finished. Realize the complete drying of all tobacco leaves.

2. Flue-cured tobacco leaves with high water content (tobacco leaves with high water content are formed by excessive rain at maturity). ① Yellowing stage. When igniting, close the doors and windows and open the skylight appropriately. The dry bulb temperature was raised to 38℃ at 65,438 0℃/hour, and kept stable at 38℃ ~ 40℃ for a long time, and then raised to 42℃ ~ 43℃ at 65,438 0℃/hour, so that the change of tobacco leaves met the requirements. The wet bulb temperature rises synchronously, and the difference between wet and dry is about 3℃. The standard of tobacco change is: at 38℃ ~ 40℃, the tobacco leaves in the bottom shed turn yellow by 40% ~ 50%, the leaves become soft, and at 42℃ ~ 43℃, the leaves turn yellow by 70%, and the main veins become soft. ② Fixing stage. The dry bulb temperature is raised to 45℃ for 2 ~ 3 hours at 1℃, and it is kept at 45℃ ~ 48℃ for a long time until all the tobacco leaves in the curing barn turn yellow and dry into small rolls, then it is raised to 54℃ ~ 55℃ at 0.5℃~ 1℃/ hour, and the temperature is kept stable until the leaves dry into large rolls. Before the dry bulb temperature is 50℃, the wet bulb temperature is stable at 36℃ ~ 38℃, and after 50℃, the wet bulb temperature gradually increases to 65438 0℃. The drying stage is the same as that of ordinary tobacco leaf baking.

3. Flue-cured tobacco leaves with low water content (formed by long-term drought in growth and maturity). ① Yellowing stage. When igniting, close doors and windows, skylights and underground holes. The dry bulb temperature is raised to 34℃ ~ 36℃ at 65,438 0℃ for 1 ~ 2 hours, and then raised to 38℃ ~ 40℃ at 65,438 0℃/hour after the temperature is stable, so that 90% ~ 100% of the tobacco leaves in the bottom shed turn yellow. The wet-dry difference is about 65438 0℃. When the temperature difference is too large, add water to make up the humidity. ② Fixing stage. Raise the temperature to 45℃ at 1℃/ hour, and keep it at 45℃ ~ 48℃ for a long time, so that the upper and middle tobacco leaves will be fully yellow and soft, and then raise the temperature to 54℃ ~ 55℃ at 1 ~ 3 hours, and keep it stable to a large cigarette leaf. The wet bulb temperature is stable at 38℃ ~ 40℃.