Produção do óleo da semente de Nim (Azadirachta indica) na mesorregião do sertão Alagoano: efeito da secagem e do método de extração

Abstract

The Indian plant Azadirachta indica, popularly known as Indian Nim, produces a high-oil, high-value seed. Currently, it is present in approximately 70 hectares of the town of Olho d'Águinha, belonging to the municipality of Delmiro Gouveia However, it has not been taken advantage of by difficulties of the producers in relation to the processes of beneficiation of the seed in the extraction of the oil. In view of the regional scenario found, it is feasible to optimize the process of obtaining the oil, taking as an impact factor the generation of employment, income and quality of life for the residents of the region. The fruits were collected in Olho d'Aguinha village, and the maturation stage at the time of harvesting was then evaluated to guarantee a higher oil content. The seeds were submitted to drying in different pre-treatments (with pulp, without pulp, without pulp and comminuted) and at temperatures (50, 60, 70, 80, 90 and 100°C). Each treatment was evaluated for impact on oil content. The quality of the oil was determined by acidity, iodine and saponification analyzes. The best stage of maturation for the harvest of the fruits by the farmer was defined in the range of 40-60% maturation. The mathematical model that best fit the experimental data of drying was the Page. Pretreatment and optimum temperature were determined by mechanical extraction using seeds without pulp and dried triturated at 70ºC. Under these conditions, the average oil content was 21.66%. For the dried seeds in Olho D'Águinha village, the highest yield was also found when the fruits were pulped and crushed. The average oil content was 11.61%.The values of acidity index (25.85 mg KOH / g) and saponification index (242.82 mg KOH / g) were within the range of values already mentioned in the literature. The iodine content (31.03 g of I2 / g) was below average.