Propriedades físicas e colorimétricas de grãos de girassol ao longo da secagem

Abstract

The sunflower is an oleaginous that has presented great potential for cultivation of second harvest, what has encouraged and increased its production in the last years. To promote improvements in the post-harvest of this product, the physical properties of its seeds must be known as well as the factors that influence them. Color is also one of the main physical characteristics evaluated by consumers to attest to quality, since it allows identifying from the stage of maturation to physical injuries in agricultural products. This work aimed to evaluate the apparent specific mass, the specific unit mass, the mass of one thousand seeds, the porosity and the color variation of sunflower grains of two cultivars (Altis 99 and M734) as a function of the content of water. The drying process of the grains was carried out in a greenhouse with forced air circulation at 40 ºC and the physical properties were the direct reflectance reading of the coordinates L *, a * and b * and the total color difference evaluated during this drying. The water content during drying was accompanied by mass difference, with the initial water content being known. It was observed that the reduction of the water content by the drying process influenced the physical properties of the seeds of the two cultivars studied, whereas in the coloration only the cultivar Altis99 presented alteration in two of its coordinates, L * and b *.