Efeitos da temperatura de secagem e do tempo de armazenamento sobre propriedades físico-químicas dos grãos e sobre físico-químicas, estruturais, térmicas e de pasta do amido isolado de grãos de sorgo

Abstract

The Brazilian sorghum production is approximately 2.2 million tons, occupying the eighth position in world production. Brazilian production is distributed in different regions of the country which shows the adaptation of culture to soil and climatic conditions existing in the country. The final product quality after storage is directly related to the grains quality at the harvest, however during drying and storing that quality can vary as a result of drying temperature and storage time. This study evaluated the effects of drying temperature and time of storage on parameters grain quality and properties of starch in sorghum grains. The grains were produced in Aceguá municipality, Rio Grande do Sul, and harvested with moisture content around 22%. The drying was performed in stationary dryer utilizing temperatures of 25, 45, 65 and 85 ° C until the grains reach the moisture close to 12.5%. The grains were stored at a temperature of 16 ° C for a period of six months. The evaluations were performed at the beginning of grain storage, in three and in six months. The drying of grain sorghum at 85 ° C showed an inverse pattern to the control dried at 25 ° C, causing changes in the starch granules. The results showed that the best physico-chemical characteristics occurred at the temperature of 45 ° C.