Resistance of edible beans to compression

The objective of this work was to evaluate the force–deformation data of edible beans by using elastic parameters as function of grain moisture content.Edible beans with moisture contents varying from 0.13 to 0.42 (dry basis) were compressed uniaxially between two parallel rigid plates in natural repose position with a force application rate of 0.001 m s−1. The proportional modulus of deformability was determined for the deformation values obtained were: 0.4 × 10−3, 0.8 × 10−3, 1.2 × 10−3, 1.6 × 10−3, and 2.0 × 10−3 m. The results showed that the compression needed to cause edible beans deformation decreased as the moisture content increased. Higher moisture contents resulted in a decreased force at failure. The proportional modulus of deformation values found varied between 4.1 and 71.3 × 107 Pa, rising as the moisture content decreased. The sigmoidal model, described by Taylor’s series, appropriately represent the force–deformation curve of edible beans in compression for different moisture contents and allowed a good identification of the generally applied elastic parameters. The values of maximum tangent and secant decreased with the increase of the moisture content of edible bean.