Title: The use of grapeseed oil for the production of structured lipids catalyzed by a recombinant Rhizopus oryzae lipase
Author: Suzana Dias
Last saved by: Saritas, Sevim
Company: Galp Energia

Storage Stability of Seeds from Jatropha curcas L. grown in Mozambique
J. Rodrigues^(1), I. Miranda^(2), J. Gominho^(2), M. Vasconcelos^(3),
 G. Barradas^(3), H. Pereira^(2), F. Bianchi-de-Aguiar^(3), S. Ferreira-Dias^(1)
^(1)Universidade de Lisboa, Instituto Superior de Agronomia, CEER, Tapada da Ajuda, 1349-017 Lisbon, Portugal; ^(2)Universidade de Lisboa, Instituto Superior de Agronomia, CEF, Tapada da Ajuda, 1349-017 Lisbon, Portugal;^(3)GALP Energia, Unidade de Biocombustíveis, Rua Tomás da Fonseca, 1600-209 Lisbon, Portugal.

During the last decade, Mozambican farmers were encouraged to grow Jatropha curcas L. as a cash crop in systems that do not compete with food production, such as hedges, fences, ridges or wide intercropping systems, as a source of oil for biodiesel production, to overcome the needs for oil importation for energy purposes. However, the lack of biodiesel production units near Jatropha production areas brought problems related to seed conservation until oil extraction and/or oil storage until conversion into biodiesel. The aim of this study was to evaluate the stability of (i) the oil in the seeds and (ii) of the extracted oil, during storage under controlled moisture and temperature values simulating tropical climate conditions. Seeds from plants of two different accessions and grown in the same plantation, were used. Seeds from accession A and their respective oils, with an average content of 89.1 mg/kg of gamma-tocopherol (natural antioxidant), were stored during 45 days and 6 months, respectively, at 28ºC or 35ºC, and relative humidity of 75 % or 92 %. Seeds from accession B, with higher amounts of gamma-tocopherol in their oil (181.8 mg/kg), were also stored at 35ºC, and relative humidity of 75 % or 92 % for 45 days. The high humidity conditions promoted the growth of fungi such as Penicillium sp. and Aspergillus sp. on seeds, which were responsible for oil degradation, via hydrolysis and enzymatic oxidation, during seed storage. However, the oil in seeds from accession B showed higher resistance to oxidation than that in seeds from accession A, with 1.5 or 2.8 times decrease in the amounts of first and secondary oxidation products, after 45 days of storage at 35ºC and 92 % of relative humidity, respectively. The oil stored in closed glass containers exhibited a high oxidative stability during 6 months of storage at 28ºC or 35 ºC. Therefore, under tropical conditions, it is better to extract the oil and store it under closed containers without contact with oxygen and light, until its conversion into biodiesel, than to store the seeds.