Physical and Chemical Changes in Yellow Sun-cured Tobacco during Curing

The physical and chemical changes in yellow sun-cured tobacco during curing were studied with improved and traditional sun-curing processes.The results showed that the moisture and chlorophyll contents in tobacco leaf decreased gradually, total nitrogen content changed little, nicotine content declined slightly as the advance of curing.At the yellowing stage, the contents of starch and protein reduced gradually and the contents of total sugar and free amino acid increased.By comparison, the improved process demonstrated that the dehydrating rate of tobacco le aves was slower at yellowing stage, which benefited to the degradation of chlorophyll, starch and protein, resulted in enhanced aroma and quality.