Tob. Sci., 1969, 13-54, p. 171-175, ISSN.0082-4523

Environmental conditions for curing burley tobacco

Department of Agricultural Engineering, University of Kentucky, Lexington, Kentucky USA

The objectives were to fit the exponential equation to observed weight loss vs time curves for burley tobacco during the cute, to establish the relative rate of weight loss for various components of the tobacco plant, and to determine the optimum drying rates for primed and stalk-cured burley tobacco, based on average support prices and chemical analyses of the leaves. The rate constant, k, is defined by the exponential equation (M-Mₑ)/ (Mₒ-Mₑ) =e-kt where M=moisture content, dry weight basis; Mₒ= initial moisture content; Mₑ= equilibrium moisture content; and t= time, hr. The value of k for the laminae, whole leaves, whole plants, midribs, and stalks were derived. The ratios of lamina k-values over component k-values were 1.00, 1.53, 2.76, 3.05, and 6.94, respectively, averaged over various environmental conditions. There was no direct connection between rate or weight loss and price per pound. However, the temperature and drying rate history did effect the price per pound and the total nitrogen and protein nitrogen levels. Samples which were cured in a conventional barn without environmental control showed a lower rate of curring and a lower support price than samples cured at a higher temperature with environmental control.