A method of estimating the filling capacity of tobacco shreds obtained by blending two kinds of tobacco leaves, which have different filling capacity, was investigated. Tobacco leaves used in this experiment were sampled from five stalk positions of a Flue-cured variety (BY4) and from a domestic Air-cured one (Matsukawa). After shredding, each sample from the Flue-cured variety was blended in various proportions with each sample from the Air-cured one, and the filling capacity of the blended shreds was measured.
The essential results obtained were as follows:
(1) The experimental value ((FC)bE) of filling capacity of blended shreds was represented by the following formula,
(FC)bE=k1+k2M+k3M2,
where M indicates the weight per cent of the Flue-cured in blended shreds. The variation of (FC)bE with M was found to be shown as a convex curve.
(2) Being based on our previous finding that there was a high correlation between filling capacity of shreds and tensile elastic modulus of leaf, the variation of composite compressive elastic modulus (Eb) of blended shreds was calculated with the change of M, on the assumptions that tobacco shreds have perfect elasticity and that they are arranged in parallel with compressive force. It was found that the change of Eb with M was very similar to that of (FC)bE.
(3) For practical use, the next linear formula ((FC)bA) could be applied to an estimation of filling capacity of blended shreds,
(FC)bA={(FC)1×(M/100)}+{(FC)2×(100-M)/100},
where (FC)1 and ((FC)2 indicate the filling capacity of the Flue-cured and that of the Air-cured, respectively. The maximum difference between (FC)bE and (FC)bA was less than 8% of the (FC)bA.
