• Food Science and Biotechnology
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• v.16 no.6
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• pp.981-987
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• 2007

Effects of lignan compounds (sesamol, sesamin, and sesamolin) extracted from roasted sesame oil on the autoxidation at $60^{\circ}C$ for 7 days and thermal oxidation at $180^{\circ}C$ for 10 hr of sunflower oil were studied by determining conjugated dienoic acid (CDA) contents, p-anisidine values (PAV), and fatty acid composition. Contents of lignan compounds during the oxidations were also monitored. ${\alpha}$-Tocopherol was used as a reference antioxidant. Addition of lignan compounds decreased CDA contents and PAY of the oils during oxidation at $60^{\circ}C$ or heating at $180^{\circ}C$, which indicated that sesame oil lignans lowered the autoxidation and thermal oxidation of sunflower oil. Sesamol was the most effective in decreasing CDA formation and hydroperoxide decomposition in the auto- and thermo-oxidation of oil, and its antioxidant activity was significantly higher than that of ${\alpha}$-tocopherol. Sesamol, sesamin, and sesamolin added to sunflower oil were degraded during the oxidations of oils, with the fastest degradation of sesamol. Degradation of sesamin and sesamolin during the oxidations of the oil were lower than that of ${\alpha}$-tocopherol. The results strongly indicate that the oxidative stability of sunflower oil can be improved by the addition of sesamol, sesamin, or sesamolin extracted from roasted sesame oil.

• Food Science and Biotechnology
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• v.18 no.2
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• pp.356-361
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• 2009

Lipid oxidation and contents of tocopherols and phospholipids (PL) in soy-added fried products during storage in the dark were studied. Flour dough containing soy flour at 0, 10, 20, and 30% on a weight basis was fried in corn oil at $180^{\circ}C$ for 2.5 min. The fried products were stored at $60^{\circ}C$ for 11 days in the dark. Lipid oxidation of the fried products was evaluated by conjugated dienoic acid (CDA) and p-anisidine values (PAV). Tocopherols and PL were determined by high performance liquid chromatography (HPLC). CDA contents and PAV of the fried products were increased during storage, and addition of soy flour improved lipid oxidative stability of the fried products, which was partly related to increased amount of tocopherols and PL in the soy-added fried products. Tocopherols and PL were degraded during the dark storage of the fried products. Soy flour addition to the dough did not affect the rate of tocopherols degradation during storage of the fried products; however, PL degradation was higher in the soy-added fried products. Residual amounts of $\alpha$-tocopherol and phosphatidylinositol showed high correlations with the lipid oxidation of the fried products during storage in the dark.

• Journal of Sensor Science and Technology
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• v.22 no.4
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• pp.239-243
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• 2013

Several methods are available to measure the oxidation of edible oils, such as their acid, peroxide, and anisidine values. However, these methods require large quantities of reagents and are time-consuming tasks. Therefore, a more convenient and time-saving way to measure the oxidation of edible oils is required. In this study, an edible oil-condition sensor was fabricated using single-walled nanotubes (SWNTs) made using the spray deposition method. SWNTs were dispersed in a dimethylformamide solution. The suspension was then sprayed using a spray gun onto a prefabricated Au/Ti electrode. To test the sensor, oxidized edible oils, each with a different acid value, were prepared. The SWNT sensors were immersed into these oxidized oils, and the resistance changes in the sensors were measured. We found that the conductivity of the sensors decreased as the oxidation level of the oil increased. In the case of the virgin oil, the resistance change ratio in the SWNT sensor S(%) = {[(Rf - Ri)]/Ri}(%) was more than 40% after immersion for 1 min. However, in the case of the oxidized oil, the resistance change ratio decreased to less than that of the response of the virgin oil. This result suggests that the change in the oil components induced by the oxidation process in edible oils is related to the conductivity change in the SWNT sensor.

• Food Engineering Progress
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• v.21 no.1
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• pp.49-56
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• 2017

Vegetable seed oils (VSOs) have been extracted and used not only as ingredients in food and as sources of dietary lipids, but also as sources of nutraceuticals used to overcome the various oxidative stresses that contribute to the development of diseases, including cancer and other chronic conditions. The chemical compositions and oxidative stabilities of various VSOs were therefore investigated; samples were stored for 35 d, with each oil having been tested under $O_2$ exposure, sealed from $O_2$ exposure and sealed from $O_2$ exposure while containing $O_2$ scavengers. Oxidative stability was evaluated by peroxide value (POV), p-anisidine value (p-AnV), iodine value (IV), and thiobarbituric acid (TBA) value. Perilla seed and flaxseed oil were mostly composed of linolenic acid (45.5% and 59.7%, respectively), whereas pine seed oil was mostly composed of linoleic acid (48.3%). Meanwhile, camellia seed and olive oils contained 80% oleic acid, which correlated strongly with oxidative stability. The POV, p-AnV, and TBA values were the highest under $O_2$ exposure, and the lowest in the presence of $O_2$ scavengers. These results indicate that VOS oxidative stability depends not only on storage conditions, but on unsaturated fatty acid profiles as well.

• Korean Journal of Food Science and Technology
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• v.26 no.6
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• pp.824-827
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• 1994

Sardine oil was vacuum-steam deodorized at $170^{\circ}C$ with acid (acetic and citric acid) and ethanol solution as steam sources. Glycerol was added to fish oil to remove volatile odorous constituents. The storage stability of deodorized fish oil was determined by totox value, secondary parameter obtained from peroxide and anisidine values. Both deodorization with acetic acid solution and addition of glycerol to the oil resulted in improved storage stability. The totox values of fish oil deodorized with water, glycerol+water and glycerol+acetic acid solution were 936, 611, and 443, respectively after 10 days at $30^{\circ}C$. The result showed that acetic acid seemed to destroy the odorous constituents and glycerol accelerated the removal of odorous constituents, such as amines in fish oil.

• Korean Journal of Food Science and Technology
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• v.26 no.6
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• pp.655-658
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• 1994

This study was designed to investigate the suitability of oxidation matters and physico-chemical characteristics as a quality evaluation for the extent of rancidity development in fats and oils undergoing thermal oxidation. The results showed that acid value rapidly increased during heating time. Soybean oil, especially revealed a faster increase than palm oil and palm olein. Anisidine value and conjugated diene value also increased. Especially, soybean oil increased more rapidly than palm oil and palm olein. Active oxygen method stability was good in the ranks of palm oil, palm olein and soybean oil. Primary oxidation matter (POM) and secondary oxidation matter (SOM) were surveyed as an evaluation method for the extent of rancidity development in fats and oils. POM and SOM showed a sharp increase during the thermal oxidation period.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.6
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• pp.2583-2589
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• 2014

Background: Soybean oil may protect against cancer of the breast and prostate. It may also exert beneficial influence in combination with other oils. Here, blends (20%, v/v) of sea buckthorn oil (SEBO), camellia oil (CAO), rice bran oil (RBO), sesame oil (SEO) and peanut oil (PEO) with soybean oil (SBO) were formulated. Materials and Methods: Oxidative stability (OS) and radical scavenging activity (RSA) of SBO and blends stored under oxidative conditions ($60^{\circ}C$) for 24 days were studied. By blending with different kinds oils, levels of polyunsaturated fatty acids (PUFA) decreased, while monounsaturated fatty acid (MUFA) content increased. Progression of oxidation was followed by measuring peroxide value (PV), p-anisidine (PAV), conjugated dienes (CD) and conjugated trienes (CT). Results: Inverse relationships were noted between PV and OS at termination of storage. Levels of CD and CT in SBO, and blends, increased with increase in time. The impact of SEO as additives on SBO oxidation was the strongest followed by RBO, CAO, SEBO and PNO. Conclusions: Oxidative stability of oil blends was better than SBO, most likely as a consequence of changes in fatty acids and tocopherols' profile, and minor bioactive lipids found in selected oils. The results suggest that these oil blends could contribute as sources of important antioxidant related to the prevention of chronic diseases associated to oxidative stress, such as in cancer and coronary artery disease.

• Journal of Aquaculture
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• v.17 no.2
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• pp.139-143
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• 2004

In the fish oil forced oxidized at 6$0^{\circ}C$ for 10 days, changes in the levels of peroxide (POV), anisidine (AnV), total oxidation (Totox), iodine (IV), acid (AV) and fatty acids composition were measured. The levels of POV, AnV and Totox remained unchanged or decreased after reaching the maximum. The concentrations of polyunsaturated fatty acids (PUFA) such as Docosa hexaenoic acid (DHA) or Eicosa pentaenoic acid (EPA) decreased with extended oxidation of fish oil. In saturated fatty acids (SFA) like C16:0, their concentration increased with decreasing PUFA. The ratios of PUFA/SFA and DHA/C16:0 decreased with extended oxidation of fish oil. Using a single parameter of POV, AnV, Totox, AV, IV, or fatty acids for evaluation of the quality of fish oil may prove difficult. Besides other parameters, the ratios of PUFA/SFA and/or DHA/C16:0 could be a good index to evaluate the quality of fish oil.

• Korean journal of food and cookery science
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• v.29 no.6
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• pp.805-814
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• 2013

Lotus root, dried laver, and perilla leaf bugak, Korean traditional fried cuisine, were prepared with fermented glutinous rice batter and unroasted sesame oil or wheat flour batter and soybean oil and their physicochemical characteristics was evaluated. Bugak with fermented glutinous rice batter and unroasted sesame oil showed higher hardness, possibly brittleness than bugak with wheat flour batter and soybean oil. Oil absorption was higher in bugak with fermented glutinous rice batter and unroasted sesame oil than bugak with wheat flour batter and soybean oil, however, the lipid oxidation, evaluated by conjugated dienoic acid and p-anisidine values, was significantly lower in bugak with fermented glutinous rice batter and unroasted sesame oil. Frying oil strongly influenced the degree of lipid oxidation and fatty acid composition of bugak lipid. Different preparation of bugak did not show great effects on the contents of chlorophylls and carotenoids of dried laver and perilla leaf bugak, possibly due to protection by rice or wheat flour batter coating.

• Korean Journal of Food Science and Technology
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• v.40 no.6
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• pp.611-620
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• 2008

The principal objective of this study was to assess the effects of phosphatidylcholine (PC) and phosphatidylethanolamine (PE) extracted from egg yolk on the oxidation of tocopherol-stripped canola oil and its browning, as well as their content changes during 12 hr of heating at $180^{\circ}C$. PC and/ or PE contents in the oil were measured at 200, 500, 1,000, or 2,000 ppm. PL contents in the oil and oil browning were determined by high performance liquid chromatography (HPLC) and spectrophotometry, respectively. The oil oxidation was evaluated by the combination of fatty acid composition, conjugated dienoic acid content, and p-anisidine value. PC was degraded at a slower rate than PE during heating and the co-presence of PE reduced its rate of degradation. PE increased oil browning more profoundly than PC did. PC significantly reduced oil oxidation during heating; however, we noted a possible antagonism between PE and PC in reducing the oil oxidation. Egg yolk PC was a better antioxidant in oil oxidation during heating.