Determinação das propriedades físicas de grãos de girassol em diferentes temperaturas de secagem

Abstract

The sunflower is an annual crop with several purposes, whose grains, like other crops, after harvesting need to be subjected to drying to be stored safely. This operation reduces the water content and conditions the grains for proper conservation, but can also provide physical changes in the structure of the product. Thus, the objective of this work was to evaluate the effects of drying at different air temperatures on the physical properties of different varieties of sunflower: M734 and Altis 99. For this, grain samples were separated and dried at temperatures of 40, 50, 60, 70 and 80 °C until reaching a final water content of about 9%. After drying, the physical properties were determined: circularity, sphericity, electrical conductivity of the exudate solution of the grains and the color. Based on the results obtained, it was concluded that the circularity, sphericity and color of the grains were not influenced by the drying temperatures. However, the electrical conductivity of the exudate solution of the sunflower grains, of the two varieties studied, increased with the drying temperature.