• Korean Journal of Food Science and Technology
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• v.32 no.6
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• pp.1213-1220
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• 2000

The mutagenicity of the thermally oxidized soybean oils was investigated. Each oil sample was taken after 0, 8, 16, 24, 32, 40, and 48 hours of heating at a temperature of $180{\pm}3^{\circ}C$, and was used to study the changes of peroxide value(POV), acid value(AV), iodine value(IV), conjugated dienoic acid content(CDA content, %), and fatty acid composition. Another set of samples was fractionated into non-oxidized and oxidized fractions by column chromatography using silica gel. The mutagenicity of the samples taken from the thermally oxidized oils as well as the non-oxidized and oxidized fractions was investigated with the Ames test. Bacterial tester strains used in the present study were the histidine auxotrophic strains of S. typhimurium TA100, TA1535 and TA 102 for the detection of base pair, and TA98 and TA1537 for frame shift mutations. Each set of samples was dissolved in tetrahydrofuran and tested at doses ranging from 0.05 to 5 mg/plate. The oxidized fractions increased significantly the number of $His^+$ revertant colonies of TA100, TA1537 and TA102, thereby showed mutagenic activity on these strains. However none of the oil samples taken within the 48 hours oxidation period showed any mutagenic activity with and without metabolic activation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.1
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• pp.120-127
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• 2000

Deep-fat frying is a common cooking practice. There has been considerable concern regarding the mutagenic and carcinogenic potential of thermally oxidized oils. Studies on deep-fried foods so far have revealed not much on the mutagenicity of the oils in the foods. Therefore, in the present study, it was attempted to investigate the mutagenicity ofthe thermally oxidized safflower oil. Oil was heated in a home-fryer at a temperature of 180$\pm$3$^{\circ}C$ for 48 hours. Oil samples were taken at 0, 8, 16, 24, 32, 40 and 48 hours of heating, respectively. Each sample was used to study the changes in peroxide value (POV), acid value (AV), iodine value (IV), conjugated dienoic acid (CDA) content, %, and fatty acid composition. Another series of samples were fractionated into non-polar and polar fractions by column chromatography. The mutagenicity of the samples taken from the thermally oxidized oils, as well as the non-polar and polar fractions of the thermally oxidized oils, was investigated with the Ames test. The Ames test was carried out with and without metabolic activation. Bacterial tester strains used in the present study were the histidine auxotrophic strains of Salmonella typhimurium TA100, TA1535 and TA102 were used for the detection of base pair mutations, and TA98 and TA1537 for frame shift mutations. Each series of samples was dissolved in tetraphydrofuran (inhibitor-free) and tested at doses ranging from 0.05 to 5 mg/plate. None of the oil samples taken during the 48 hour oxidation period showed any mugagenic activity. This was the case, even after the activaton with 59 mix. Also, none of the polar and non-polar fractions showed any mutagenic activity on all the strains tested.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.4
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• pp.313-320
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• 1984

In order to elucidate the oxidative stabilities of mackerel lipids, lipids were extracted from ordinary muscle, dark muscle, skin (including subcutaneous adipose tissue) and viscera, and then stored at $30^{\circ}C$. The changes of lipids were examined periodically by measuring peroxide value (POV), thiobarbituric acid (TBA), weighing method, acid value (AV) and iodine value (IV), Fatty acid composition of lipids was analyzed by GLC. The results obtained are summerized as follows: The velocity of lipid oxidation during the storage was differ from the extracting part of the sample. It was laster in skin, viscera, dark muscle and ordinary muscle in the order. Ratio of polar lipid fractions in total lipids was ranged from 5 to $15\%$, and the highest result was observed in dark muscle. Main fatty acids of the lipids were $C_{16:0}$ acid ($22.0{\sim}25.9\%$), $C_{18:1}$ acid ($22.3{\sim}26.7\%$) and $C_{22:6}$ acid ($9.6{\sim}13.4\%$), and $C_{22:6}$ acid content ($\%$) was the highest in lipid from dark muscle, and the lowest in lipid from skin. Monoenoic acid content ($\%$) was higher in the non-polar lipid than in the polar lipid, on the contrary. polyenoic acid content ($\%$) was higher in the polar lipid than in the non-polar lipid. Polyunsaturated fatty acids of the lipids, $C_{20:5}$ acid and $C_{22:6}$ acid, decreased predominantly with oxidation during storage, while saturated acids, $C_{14:0}$ acid and $C_{16:0}$ acid, increased predominantly. The polar lipid fractions were oxidized much faster than the non-polar lipid fractions.