• Korean Journal of Food Science and Technology
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• v.21 no.4
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• pp.468-479
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• 1989

The oxidative stability of the ramyon prepared with rapeseed oil fortified with antioxidants or blended with palm oil was studied to explore the possibility of substituting it for Imported frying fats and oils. Natural tocopherols, butylated hydroxyanisole(BHA), tertiarybutyl hydroquinone(TBHQ), and ascorbyl palmitate with citric acid were used at a level of 0.02 percent. Blended oils were prepared by adding a palm oil to the rapeseed oil at ratios of 7:3, 5:5, and 3:7(w/w), respectively. Ramyon samples were stored at $35.0{\pm}0.5^{\circ}C$. for 90 days. The values of parameters, such as peroxide value, unsaturation ratio, and dielectric constant, of the extracted oils were regularly determined. An organoleptic test for the flavor of the samples was also performed. The oxidative stability of the samples was estimated on the basis of the changes of the parameter values. The effectiveness of the antioxidants was in the order of TBHQ ${\gg}$ ascorbyl palmitate with citric acid>BHA>natural tocopherols. The oxidative stability of the ramyon prepared with the rapeseed oil containing 0.02 percent TBHQ was almost as good as that of the ramyon prepared with the palm oil. The stability of the ramyon prepared with the blended oil containing 70 percent palm oil was also as good as that of the ramyon prepared with the palm oil.

• Korean Journal of Food Science and Technology
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• v.17 no.6
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• pp.500-505
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• 1985

A method to store concentrated milk in the liquid state at $-15^{\circ}C$ was developed, and quality changes during storage of milk were evaluated. Combined cryoprotectants (CCP) suitable for storing concentrated milk in the liquid state at $-15^{\circ}C$ were consisted of 17.74% sucrose, 8.87% glucose, 8.87% fructose, 2% glycerol, 0.25% sodium hexametaphosphate, 0.25% NaCl and 0.02% ascorbic acid. The amount of CCP to be added to concentrated milk to depress freezing point to $-15^{\circ}C$ was 38% by weight. Gelation due to protein denaturation was the most serious quality change during storage, which adversely affected appearance and utilization of the stored product. Gelation was observed after 3 weeks storage in the control, but it was not in milk with CCP throughout 18 weeks storage. Amount of protein precipitated increased in the control during storage, whereas there was no protein precipitated in milk with CCP. Surface color and peroxide value of the control and treatment did not change significantly during storage, and there were no marked differences between the control and treatment. These results indicated that quality of concentrated milk could be preserved, without gelation, by storing milk with CCP in the -liquid state at the frozen storage temperature. Besides, energy required for freezing preservation of milk could be significantly reduced by elimination of phase changes for freezing and thawing, and the stored product could be continuously processed for the final products without long waiting time for thawing.

• Korean Journal of Food Science and Technology
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• v.40 no.1
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• pp.15-20
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• 2008

This study investigated the antioxidant content and oxidative properties of roasted sesame oil during manufacturing and storage at $25^{\circ}C$ in the dark for 18 months. The manufacturing steps included pressing of the roasted sesame seeds, and then three filtering steps. Filtering decreased the oil viscosity, but increased free fatty acid content. The peroxide value (POV) was not affected by filtering. Sesamin, sesamolin, and tocopherol levels were significantly higher in the $3^{rd}$ filtered oil as compared to the other oils; however, sesamol content was reduced. The roasted sesame oil oxidized slowly during storage at $25^{\circ}C$ in the dark, and there was no POV change up to 9 months of storage. The levels of sesamol, sesamin, sesamolin, and tocopherols in the oil decreased with storage time, and the tocopherol decomposition rate (-3.04%/month) was higher than that of total lignan compounds (-1.06%/month). Therefore, these results suggest that tocopherols have priority over lignan compounds in performing as antioxidants in roasted sesame oil during storage.

• Korean journal of food and cookery science
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• v.2 no.1
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• pp.38-44
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• 1986

Effects of the kind and concentration of salt on oxidation of lipids and on formation of flavor components have been studied with four varieties of fermented anchovies prepared with 20％ sun-dried salt(sample B) , 12% refined salt (sample C), 16.5％ refined salt (sample D) and 16. 5% refined salt Plus 25％ brine (sample E). The sample B showed higher peroxide and TBA value and also higher content of TMA thar. those prepared with refined salt. The amounts of amino-N and VBN in sample B appeared larger than in sample D but was in a similar level with those in sample C. On the other hands, much smaller amounts of lactic and succinic acid were observed in sample B compared with in sample C and D. Sample C revealed the highest level of lactic acid among the samples tested. The changes in the amounts of each free amino acid displayed similar tendencies in all samples, except decreasing tendency of tyrosine in sample B and increasing tendency of aspartic acid in sample C. Also observed was lower IMP and inosine level in sample B than in C and D, but hypox-anthine level was higher in B. In general, sample I indicated remarkably lower values of experimental data in all cases mentioned above, but the highest TBA balue.

• Korean journal of food and cookery science
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• v.15 no.2
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• pp.158-162
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• 1999

A beverage was manufactured with onion extract for which onions were boiled with water and filtered. The concentration of cyclodextrin was studied to improve its quality in manufacturing the onion beverage and its antioxidative and antifatigue effect was investigated in vitro or in vivo. One percent of cyclodextrin was optimum concentration to prevent precipitation and to remove pungent taste and keep mild taste during storage at room temperature and 40$^{\circ}C$. Water extract of onion, used to manufacture onion beverage shown significant difference in antioxidative effect based on peroxide value and thiocyanate method. For the study of antifatigue, swimming performance of mice which fed with onion beverage and water extracts of onion and garlic for 2 weeks was investigated. The mice fed with onion beverage swam longer than those fed with water extract of onion and garlic.

• Korean Journal of Food Science and Technology
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• v.27 no.5
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• pp.635-639
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• 1995

The effective extraction of antioxidative substances from soybean was investigated by using various solvents, such as water, ethanol, methanol, acetone, chloroform, benzene, ethyl acetate, ether, dichloromethane, and hexane. Extraction was performed by cold method at $30^{\circ}C$ and by reflux method at $85^{\circ}C$. The antioxidative effect of the extracts was determined by peroxide value during the oxidation of soybean oil containing the extracts at $105^{\circ}C$ for 10 hours, and also by TBARS(thiobarbituric acid reactive substances) formed during the peroxidation of egg lecithin liposomes. The antioxidant activity of the extracts from raw soybean was higher than that from defatted soybean. The antioxidant activity of the extracts by reflux method was higher than that by cold method. The methanol extract from defatted and roasted soybean(DRS) showed the highest antioxidative effect against oxidation of soybean oil, while the water extract from DRS in egg lecithin liposomes. In the peroxidation of egg lecithin liposomes, the antioxidative effect of polar solvents extracts were higher than those by nonpolar solvents extracts.

• Journal of the Korean GEO-environmental Society
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• v.13 no.10
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• pp.69-76
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• 2012

This study focuses both on the quantitative measurement of hydroxyl radicals formed by an electron beam (E-beam) process and on the decomposition of pentachlorophenol(PCP) in the presence of $H_2O_2$ and $Fe^{3+}-EDTA$ as additives. To attain this objective, the quantitative measurement of hydroxyl radical was performed with the hydroylation of benzoic acid (BA), producing hydroxybenzoic acid (OHBA). As a result, the concentrations of hydroxyl radical measured were lower than those of hydroxyl radical predicted. Probably, it indicates that the reactive species generated during E-beam irradiation are able to scavenge the hydroxyl radicals. In particular, the degradation of PCP was promoted by the addition of $H_2O_2$ (< 1mM). On the other hand, its degradation as well as the generation of chloride ions as a by-product was inhibited by the addition of $H_2O_2$ (> 1mM), and thus carbon yield(%) of oxalic acid as a by-product was increased. During E-beam irradiation the addition of $Fe^{3+}-EDTA$ effectively decomposed the PCP, thus increasing the G-values. Considering the formation of OHBA and the decomposition of PCP, these results suggest that the addition of $Fe^{3+}-EDTA$ in the E-beam process can produce the further hydroxyl radicals and enhance the efficiency of PCP decomposition at low dose.

• Korean Journal of Plant Resources
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• v.24 no.1
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• pp.30-39
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• 2011

This study was conducted to investigate the antioxidative activity and cytotoxicity of fermented Allium victorialis extract. The results were as follows; The total polyphenol content of A. victorialis extract was 2.63 mg/g, and that of fermented A. victorialis extract was 1.65 mg/g which decreased a little by fermentation. The total flavonoid content of A. victorialis extract was 57.77 mg/g, and that of fermented A. victorialis extract was 62.27 mg/g, and this could increase a little from fermentation. Electron donating ability of A. victorialis extract was lower than vitamin C(97.71%), but before fermentation it was 82.29% and after fermentation it became 82.40%. Nitrite scavenging ability of A. victorialis extract before and after fermentation showed lower numerical value than that of butylated hydroxytoluene(BHT) at pH 2.5 but that of A. victorialis extract expressed higher than that of BHT. Superoxide dismutase-like activity showed relatively low level, 15%. Nitrite production increased by A. victorialis extract but was inhibited after fermentation. Methyl diamphetamine (MDA) content was inhibited with increased concentration of A. victorialis extract compared with $H_2O_2$ treatment but there was not any difference before and after fermentation. Therefore, production of lipid peroxide(LPO) was inhibited by A. victorialis extract. Cell viability of fibroblast cell was tend to slightly decrease with increased concentration of A. victorialis extract, but not different with control.

• Journal of Ginseng Research
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• v.41 no.2
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• pp.169-179
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• 2017

Background: Ginsenosides are the main pharmacological components of Panax ginseng root, which are thought to be primarily responsible for the suppressing effect on oxidative stress. Methods: 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity and oxygen radical absorption capacity were applied to evaluate the antioxidant activities of the ginsenosides. Human embryonic kidney 293 (HEK-293) cells were incubated with ginsenosides extracted by pulsed electric field (PEF) and solvent cold soak extraction (SCSE) for 24 h and then the injury was induced by $40{\mu}M$ $H_2O_2$. The cell viability and surface morphology of HEK-293 cells were studied using MTS assay and scanning electron microscopy, respectively. Dichloro-dihydro-fluorescein diacetate fluorescent probe assay was used to measure the level of intracellular reactive oxygen species. The intracellular antioxidant activities of ginsenosides were evaluated by cellular antioxidant activity assay in HepG2 cells. Results: The PEF extracts displayed the higher 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity and stronger oxygen radical absorption capacity (with an oxygen radical absorption capacity value of $14.48{\pm}4.04{\mu}M\;TE\;per\;{\mu}g/mL$). The HEK-293 cell model also suggested that the protective effect of PEF extracts was dose-dependently greater than SCSE extracts. Dichloro-dihydro-fluorescein diacetate assay further proved that PEF extracts are more active (8% higher than SCSE extracts) in reducing intracellular reactive oxygen species accumulation. In addition, scanning electron microscopy images showed that the HEK-293 cells, which were treated with PEF extracts, maintained more intact surface morphology. Cellular antioxidant activity values indicated that ginsenosides extracted by PEF had stronger cellular antioxidant activity than SCSE ginsenosides extracts. Conclusion: The present study demonstrated the antioxidative effect of ginsenosides extracted by PEF in vitro. Furthermore, rather than SCSE, PEF may be more useful as an alternative extraction technique for the extraction of ginsenosides with enhanced antioxidant activity.

• Korean journal of food and cookery science
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• v.9 no.1
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• pp.33-36
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• 1993

This study was carried out to investigate the thermal stability of gingerol from Ginger and effect of its concentration on the oxidation of soybean oil. After Heating gingerol, the contents of remained gingerol was measured by HPLC. After heat treatment at $105^{\circ}C$ for 3 hours, 94.5% of gingerol was remained, whereas at $165^{\circ}C$ for 30 min., only 10% of gingerol was remained. Crude gingerol was also added to soybean oil at the concentration of 0.02%, 0.1% and 0.2% by weight of oil, respectively. The oils with crude gingerol were heat-treated at $105^{\circ}C$ for 5 hours and $165^{\circ}C$ for 30 minutes, respectively, and then the heat-treated oils were incubated at $45^{\circ}C$ for 25 days. The peroxide value of the oils was measured in order to estimate the antioxidant activity of crude gingerol compared with BHT. In the soybean oil heated at $105^{\circ}C$ for 5 hours, crude gingerol showed antioxidant activity at all concentration and the activity was more effective than 0.02% BHT. And during the storage of the heat-treated oils at $45^{\circ}C$, the antioxidant activity of crude gingerol increased in direct proportion to its concentration. In the soybean oil heated at $165^{\circ}C$ for 30 minutes and then stored at $45^{\circ}C$, the antioxidant activity of crude gingerol increased in direct proportion to its concentration.