An electrical conductivity method suitable for quantitative mechanical damage evaluation

摘要

This investigation deals with the suitability of a method, based on electrical conductivity measurements, to evaluate mechanical damage in soybeans. Two modifications on the electrical conductivity test methodology, used on seed qualityevaluation, were made: the utilization of a new number of grains per volume of water; and the introduction of a stirring process. Samples of soybeans, cultivars IAC 8 and Cristalina, were damaged by cutting the grain at the cotyledone junction and byimpact of a mass falling from different heights.Samples of varying levels of damage were soaked in distilled water and their electrical conductivities were measured during 160 mm at time intervals of 20 mm. The results showed that at soaking times other than zero, the response of electricalconductivity due to variations in percent of damage was linear for JAC 8 and quadratic for Cristalina.This technique was considered suitable for the intervals of the variables and for the conditions used in this study. The introduction of stirring process reduced detection of low level damage of samples to 20 mm.