Effect of temperature and storage time of wheat germ on the oil tocopherol concentration

• Autor(a) principal: Capitani,M.
• Data de Publicação: 2011
• Outros Autores: Mateo,C. M., Nolasco,S. M.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Brazilian Journal of Chemical Engineering
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0104-66322011000200008
• topic: Wheat germ; Storage; Oil; Tocopherols; Kinetics

Wheat germ represents approximately 3% of the grain and it contains 8-14% oil, which is a rich source of tocopherols (vitamin E) and polyunsaturated fatty acids, mainly linoleic acid. The present work shows the influence of temperature (27ºC and 45ºC) and storage time (maximum 35 days) of the wheat germ on the concentration of tocopherol in the oil. Their effect on other quality parameters was also investigated. Results indicated that oil oxidation and free fatty acid formation increased markedly with temperature and storage time. The initial sample contained 3134 µg/g total tocopherol, of which 67% was α-tocopherol and, in a lower proportions, β-tocopherol and Γ-tocopherol (30.5% and 2.4%, respectively). In the temperature range studied, tocopherols decreased as a function of storage time following first-order kinetics. The rate constant k for β-tocopherol increased with temperature. The fatty acid composition was not affected by the storage conditions applied.