RESUMEN
Comparative analysis of oils, prepared from flax, sesame and silybum seed composition, and adequate oil blends, prepared by mixing flax oil, sesame oil and silybum oil was performed. Antiradical activity was evaluated for the oils, both for their methanol-soluble phase and the fraction insoluble in methanol. DPPH radical scavenging activity expressed in Trolox equivalent antioxidant capacity. Oxidative stability during 6-month store was evaluated by peroxide value and dienic conjugates content. Oils from seed composition show the more high antiradical activity and oxidative stability than adequate oil blends. A significant correlation was found between antiradical activity and gamma-/alpha-tocopherol ratio in oils.
Asunto(s)
Antioxidantes/análisis , Radicales Libres/química , Aceite de Linaza/química , Aceite de Sésamo/química , Silybum marianum/química , Ácidos Grasos/análisis , Análisis de los Alimentos , Lignanos/análisis , Aceite de Linaza/aislamiento & purificación , Oxidación-Reducción , Aceites de Plantas/química , Aceite de Sésamo/aislamiento & purificación , Tocoferoles/análisisRESUMEN
Antioxidant activity and the oxidative stability were investigated in flax, sesame, silybum oils and oils with different omega-6/omega-3 fatty acid ratio. The content of antioxidants (AO) in crude oils and their reactivity towards peroxyl radicals were studied using kinetic method for addition of oil in a model reaction of cumol oxidation. There were correlations between PUFA/omega-9 and thermal stability (50 degrees C); between gamma-tocopherol content and resistantance to oxidative changes after storage at (10 +/- 2) degrees C for 6 months.