Determinação do teor de água da castanha-do-brasil por micro-ondas

Abstract

The Moisture content is a major factor that exerts influence on the quality of grains and seeds, and their correct determination ensures the adoption of appropriate procedures are during drying, processing and storage of the product. For Brazil nut, the officially accepted method in the country can produce overestimated results of moisture content, it has not been validated for the product in question. Thereby, this study aimed to evaluate the microwave oven method for determining the moisture content of Brazil nut. For this purpose, the experiment was conducted using samples of Brazil nut with and without shell obtained at different stages of processing. The reference method for determining the moisture content of the samples was in an oven at 90 ± 3 °C for 6 hours whose result was compared to those obtained by the microwave oven method in all the collected samples. Samples were subjected to periods of 30, 60, 90, 120 and 150 seconds of exposure to the microwave oven at full power. Comparing the data obtained by both methods, it was found that the exposure period of 120 seconds, in equipments with power output ranging from 700 to 900 W, produced moisture content values for samples that did not differ statistically from the reference method. This way, the method of microwave oven evidenced as an alternative, besides being fast and suitable for industrial and laboratory process, safe for the process of determining moisture content in Brazil nut, with and without shell.