CHANGES IN MOISTURE AND CHEMICAL COMPOSITION OF FLUE-CURED TOBACCO DURING CURING1

Abstract The present study represents a portion of an effort to develop mathematical models for predicting changes in moisture and chemical composition of flue-cured tobacco during curing. In two experiments, concentrations of chlorophyll, starch, reducing sugars, and total alkaloids (as well as moisture contents) were measured. In the first experiment, tobacco was yellowed at temperatures of 30°C, 35°C, and 40°C with 3.33°C wet-bulb depression. In the second experiment, tobacco was yellowed at 35°C with wet-bulb depressions of 1.67°C, 3.33°C, and 5°C (or approximately 89, 81, and 70% relative humidity, respectively). In general, concentrations of chlorophyll and starch in the leaves decreased during curing, whereas concentrations of reducing sugars increased, and total alkaloids remained relatively unchanged. Yellowing temperature had no significant effect on moisture content at the end of the yellowing and leaf drying stages, nor on chlorophyll at the end of the yellowing stage and starch at the end of ...