Radiação gama e secagem na conservação da qualidade do óleo de frutos de macaúba

• Autor(a) principal: Martins, Adalvan Daniel
• Data de Publicação: 2013
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/4611
• topic: Acronomia aculeata; Radiação gama; Secagem; Qualidade de óleo; Teor de óleo; Aculeata acronomia; Gamma radiation; Drying; Oil quality, Oil content; CNPQ::CIENCIAS AGRARIAS::AGRONOMIA::FITOTECNIA

The macaw palm [Acrocomia aculeata (Jacq.) Lodd. Martius ex] presents itself as a promising source of vegetable oils, especially as feedstock for biodiesel production. This is due to the high oil content in the mesocarp and almond fruit, the ability to take full utilization of these fruits, besides the great adaptability of this species to climatic conditions. However, missing information for conservation of oil quality after harvesting and storage of fruits, generating the need to develop studies that extend the shelf-life while maintaining the quality of the extracted oil. The objectives of this study were to evaluate the quality and content of mesocarp and almond oil in macaw palm fruits undergoing physical treatments of gamma radiation and drying during storage at room temperature. We carried two experiments: the first one, 120 experimental units were treated with doses of 0, 0.5, 1.0, 3.0 5.0 and 10.0 kGy of gamma radiation and stored for 0, 15, 30 , 45 and 60 days at room temperature. The interaction between dose and storage time was significant. Best visual quality was observed in fruits irradiated with higher doses, in the first days of storage. The free fatty acid from irradiated fruits were lower than the control treatment and doses of 10.0 kGy showed the highest reduction of this index. Gamma radiation reduced the oil accumulation and oxidative stability in the mesocarp. The water content in the mesocarp oil increased with increasing dose and time of storage. The oleic acid and lauric acid are present in higher quantities in the mesocarp and almond oil, respectively. Among the major fatty acids present in the mesocarp and almond oil, oleic acid is the fatty acid that presents major changes during storage. In the second experiment, 100 units experimental of macaw palm fruits were submitted to different combinations of temperature and drying time: 1) without drying the fruits (SS) 2) dried in a oven at 45°C for 4 days (45°C / 4d), 3) drying in an oven at 65°C for 4 days (65°C/4d), 4) drying in an oven at 45°C for 8 days (45°C/8d); 5) dried at 65°C for 8 days (65°C/8d). After this treatment the fruits were conducted to storage at room temperature for 0, 15, 30, 60 and 120 days. There are influence of the drying process and storage time in the evaluated characteristics. Drying at 65°C for 8 days was effective for maintaining stable the free fatty acid index of the mesocarp oil during storage. Drying restricted the accumulation of oil in the mesocarp and almond fruit. The oxidative stability was reduced by drying treatment. Higher concentrations of oleic and lauric fatty acids were found in mesocarp and kernel oils, respectively. The variations observed in the almond oil were with lower intensity than those obtained in the mesocarp oil, and oleic fatty acid is more susceptible to variation during storage. Physical treatments of gamma radiation and drying helped in preserving the fruit. Both had minor progressions in the free fatty index compared to the control treatment during storage, but the drying treatment was more effective in controlling the free fatty acid in the oil of the fruit. The oil accumulation and oxidative stability were reduced in both treatments. The drying treatment provides smaller variations in fatty acid profile for the mesocarp and almond oil.