The effect of gamma irradiation on oleic acid in methyl oleate and food

The objective of this study was to investigate the effects of gamma irradiation on changes in oleic acid of methyl oleate as well as of beef and olive oil. The samples were irradiated at doses ranging from 0 to 60 kGy and the fatty acid composition was then analyzed by GC–FID and GC–MS. Gamma irradiation upon methyl oleate induced the formation of trans octadecenoic acid and stearic acid in a dose dependent fashion, while it decreased the amount of oleic acid. These findings indicate that the 9-cis structure is responsible for the formation of trans and saturated configurations. Additionally, the formation of stearic acid was facilitated by high temperature during the irradiation. Conversely, irradiation dose and temperature during irradiation had no significant effect (p > 0.05) on the amount of trans or saturated fatty acids in the beef and olive oil.