Propriedades físicas dos grãos de soja, cotilédones e impurezas

Abstract

Due to the diversity of the characteristics of agricultural products and the presence of defects and impurities in the grain mass, it is fundamental to know the physical properties of these materials. Thus, the present work aimed to determine the physical properties for different proportions of soybean, cotyledons and impurities. The moisture content of the materials was determined in forced air circulation. The bulk density was obtained on a weight scale and the angle of rest in a transparent prism. The intergranular porosity was determined by the direct method by adding hexane. The true density was obtained analytically as a function of intergranular porosity and apparent specific mass. The terminal velocity was determined using the air column equipment. The physical properties of soybeans vary when different proportions of cotyledons and impurities are inserted into the grain mass. The angle of repose increases with the greater amount of fine impurities and the intergranular porosity increases with the presence of coarse impurities; the bulk density is higher for whole grains, while the true density is higher for coarse impurities. Grains, cotyledons, pods and impurities present variations in terminal velocity, being influenced by the moisture content, shape and size of the particles.