Influência do manejo de produção e do beneficiamento na qualidade do arroz polido e integral

Abstract

Rice is one of the most cultivated and consumed cereals in the world and the increase in crop productivity is associated with the use of high-tech cultivars and management practices, such as soil fertilization. Thus, the objective of this work was to evaluate the physical and physicochemical quality of rice grains of two cultivars IRGA 424 RI and IRGA 431 CL, cultivated under the management of different levels of fertilization (control, low, medium and high) and subjected to different processing conditions (whole and polished). The experiment was carried out in the experimental research area of the Rio Grandense do Arroz Institute (IRGA), located in Cachoeira do Sul, RS, during the 2017/18 harvest, in partnership with the Post-Harvest Laboratory (LAPOS) of the Federal University of Santa Catarina Maria (UFSM), Cachoeira do Sul Campus (CS). The experiment was carried out in a completely randomized design (2x4x2): two cultivars (CL) of rice grains, four levels of fertilization (NA) and two types of processing (BF). After harvesting, the grains were subjected to the process of husking to obtain brown rice, and husking and polishing to obtain polished rice. The physical quality analysis was performed according to the rice physical classification norms. The physicochemical analysis was performed using near infrared spectroscopy (NIR), scanning electron microscopy (SEM) and X-ray diffraction. It was concluded that there was an influence of the type of rice cultivar, the levels of fertilization and the types of processing on the physical and physicochemical quality of the grains. IRGA 431 CL cultivated with high levels of fertilization produced high quality rice grains. Brown rice had the highest percentage of whole grains, hardness index and resistance to grain breakage, and among the cultivars, IRGA 431 CL had the best result. Polished rice had the highest percentage of broken grains. With the increase in the level of fertilization, a higher whole grain yield was observed for all treatments.