Abstract: Using the stepping flue\|curing bam in Henan, effects of prolonging the time of yellowing and leaf drying on neutral aroma constituents of tobacco leaves during curing were studied. The results indicated as follows:① All of the treatments which prolonged the time of yellowing and leaf drying could increase the content of neutral aroma constituents.② The content of phenylalanine products, carotenoid, cemdrenoid, neopytadiene were highest in the treatment of T2 which prolonged the time of yellowing; Compared with normal cured treatment T1, T3 which prolonged the time of leaf drying only increased the content of carotenoid and neopytadiene. The content of maillard reaction products were the highest in the treatment of T4 which prolonged the time of yellowing and leaf drying. Compared with T1, the contents of phenylalanine products, carotenoid, neopytadiene increased and the content of cemdrenoid decreased in treatment of T4．

Key words: flue-cured tobacco, yellowing period, leaf drying period, aroma constituents