Percorrer por autor "Gominho, Jorge"
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- The implementation of the Biorefinary Concept to Jatropha curcas L. crop in MozambiquePublication . Suzana Ferreira-Dias; Gominho, Jorge; Vasconcelos, Manuel; Bianchi de Aguiar, F; Pereira, H.
- Jatropha curcas, a promising energy crop for MozambiquePublication . Suzana Ferreira-Dias; RODRIGUES, JOANA; Miranda, Isabel; Gominho, Jorge; Vasconcelos, Manuel; Barradas, Gonçalo; Pereira, H.; Bianchi de Aguiar, F
- Modeling and optimization of laboratory-scale conditioning of Jatropha curcas L. seeds for oil expressionPublication . Rodrigues, Joana; Miranda, Isabel; Gominho, Jorge; Vasconcelos, Manuel; Barradas, Gonçalo; Pereira, Helena; Bianchi-de-Aguiar, Fernando; Ferreira-Dias, Suzana
- Storage stability of Jatropha curcas L. oil naturally rich in gamma-tocopherolPublication . Rodrigues, Joana; Miranda, Isabel; Furquim, Leonnardo; Gominho, Jorge; Vasconcelos, Manuel; Barradas, Gonçalo; Pereira, Helena; et al.Jatropha curcas L. is an interesting tropical oil crop for biodiesel production. However, seed conservation until oil extraction may be a problem under high temperature and humidity. In this study, Jatropha curcas L. seeds grown in Mozambique and presenting 160 mg/kg of gamma-tocopherol in their oil were stored for 42 days, in dark, at 35 ◦C and 75% or 92% relative humidity (RH). Along storage, the oil was extracted and analysed in terms of fatty acid composition, tocopherol content, acidity, initial and final oxidation products (monitored by K232 and K270 values, respectively). Jatropha seeds presented an initial water content of 8.4% and an oil content of 45.7% (dry basis). The oil was rich in oleic (41.2%) and linoleic (38.8%) acids. Along 42 days of storage, the acidity increased from 0.8% to 7.4% and 25.3% and K270 increased from 0.07 to 0.25 and 0.46 in oils from seeds stored at 75% and 92% RH, respectively. Simultaneously, a decrease in gamma-tocopherol content was observed, which was more pronounced at 92% RH than at 75% RH (96% decrease versus 57% decrease). Gamma-tocopherol showed to protectthe oil against oxidation principally during the second stage of oxidation. During the storage at 35 ◦C, the fatty acid composition of the oils from seeds kept either at 75% or 92% of humidity, did not significantly vary throughout the test
- Variability in oil content and composition and storage stability of seeds from Jatropha curcas L. grown in MozambiquePublication . Rodrigues, Joana; Miranda, Isabel; Gominho, Jorge; Vasconcelos, Manuel; Barradas, Gonçalo; Bianchi-de-Aguiar, Fernando; Ferreira-Dias, Suzana; Pereira, H.This study evaluates the variation in oil content and composition of Jatropha curcas L. seeds from 12 origins, grown in Mozambique, under the same edapho-climatic and agronomic conditions. The seeds had oil contents from 37% to 45% (d.w.). The oils were rich in oleic (mean 40%) and linoleic (mean 40%) acids and poor in linolenic acid (mean 0.22%), with high content of beta-sitosterol (71% of total sterols), low acidity and low levels of oxidation products, making them adequate for biodiesel production by alkaline-catalyzed transesterification. Thehighlevels of gamma-tocopherol(69–182 mg/kg)may explainthehighoxidative stability exhibited by the oil during 6 months of storage at 28 or 35 ◦C. Conversely, seeds storage under high temperatures and humidity promoted the growth of fungi responsible for oil degradation. Therefore, under tropical climate conditions, when oil conversion to biodiesel is not possible immediately after fruit harvest, it is better to extract the oil and store it under closed containers without contact with oxygen and light, to preserve its quality, than to store the seed