Effects of dry and wet bulb temperature during stem-drying stage of bulk curing on aroma quality of flue-cured tobacco

Abstract

To improve aroma quality of flue-cured tobacco leaf and optimize curing technology,effects of different dry and wet bulb temperatures during stem drying stage of bulk curing on tobacco aroma components and smoking quality were studied.Results showed that,when the dry bulb temperature was 54-60 ℃,wet bulb temperature was 38 ℃ before stem-drying stage and the dry bulb temperature was 60-68 ℃,wet bulb temperature was 41 ℃ after stem-drying stage,it could remarkably increase the total contents of aroma components in tobacco leaves.And the leaves had higher contents of degradation products of carotenoid(31.250 μg/g),phenylalanine(11.426 μg/g),browning reaction(4.074 μg/g),cemdrenoid(44.329 μg/g),neophytadiene(407.909 μg/g).The content of carotenoid degraded products and megastigmatrienones(11.161 μg/g),which played important roles in improving tobacco aroma quality,increased 25.88%,35.07% compared to CK.The leaves characterized by preferable flavor notes,clean and adequate volume of aroma,moderate taste concentration and physiological strength,little irritancy and good taste scored the highest by sensory evaluation.In conclusion,the wet bulb temperature of 38 ℃ in the earlier stem drying stage and 41 ℃ in the later could significantly improve the aroma quality of flue-cured tobacco leaves.