Estudo do ponto de maturação fisiológica, secagem natural, qualidade durante o armazenamento e determinação da umidade em sementes de gergelim (Sesamum indicum L.).

Abstract

The post-harvest techniques are applied to mantain the products quality until it arrives to the consumer. With the objective to determine the ideal harvest moment and the later accompaniment of the physiological quality of sesame seeds (Sesamum indicum L.), during a period of thirteen months, stored in three packaging types (paper bag, towel bag and metallic container) and in three environments (drying chamber, Campina Grande city (Paraiba state) and Patos city PB), was set up a field and laboratory experiment with the culture CNPA G3. Used was the entirely casual statistical outlining, placed in a factorial 3 x 3 x 8 , with four repetitions. The evaluations were made by standard germination and vigour tests and by determination of moisture content and dry matter. After the physiological maturing the seeds presented dormancy. At the end of the experiment was found out that the physiological quality of the sesame seeds was affected during the storage. The metallic container packaging was the most appropriate to conserve the seeds and the environment of Patos city PB allowed the best storage. Also was studied the physiological quality during the drying process and determined the hygroscopic equilibrium curves of sesame for the temperatures of 20, 30 and 40 °C and relative humidity o f approximately 17, 29, 50, 70 and 88 %. With the experimental data were tested the equations of Henderson modified, Henderson modified by Cavalcanti Mata and Chung-Pfost. It was concluded that the natural drying didn't cause significant damage on the physiological quality o f the seed, although a reduction of the germination and vigour caused by a possible dormancy after the physiological maturing. Studying the hygroscopic equilibrium, it was verified that the equilibrium was reached most quickly at a temperature of 40 °C and that the mathematical model with the best adjustment to the experimental data was the equation of Henderson modified