• Journal of the Korean Home Economics Association
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• v.18 no.1
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• pp.41-46
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• 1980

In order to verify to what extent the rancidity of the soybean oil is occurred and how the various metal ions effect on the rancidity-as a result of applying heat to the soybean oil-the followings are obtained through experiments : 1. From analyzing the refractive index of soybean oil, The results are: the specific gravity-0.925 refractive index-1.475, saponification value-190, acetyl value-5.0, iodine value-120, peroxide value-5.0. 2. The degree of expediting rancidity take the following order : $Cu^{++}$/$Fe^{++}$/$Cr^{++}$/$Zn^{++}$/$Ni^{++}$/$Al^{+++}$. 3. The degree of expediting rancidity of $Cu^{++}$and $Fe^{++}$ is showed the abrubt increase of peroxide value in accordance with the increase of densidity. The most abrubt increase of peroxide show when the duration of heating reaches to the range between 20 minutes and 30 minutes. After heating for 60 minutes no definite variation is showed. 4. The degree of rancidity in heating the soybean oil added $Cu^{++}$, Fe and BHA shows the decrease of peroxide value by 2, 3 after adding $Cu^{++}$0.5 ppm. and heating for 30 minutes. As the result of measuring the value of peroxide after adding $Cu^{++}$ by 1.0 ppm and BHA by 0.01% and heating, peroxide shows the decrease by 7.8 when adding anti-oxidant. $Fe^{++}$ as well as $Cu^{++}$ shows that BHA prevents the metal ions from the expedition of rancidity.

• Journal of the Korean Home Economics Association
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• v.18 no.1
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• pp.25-33
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• 1980

Effect of various batter ingredients o acid value, peroxide value, darkening of oil, and changes in volume after frying at 180- $190^{\circ}C$ for 3 times were determined. Organoleptic evaluation was also performed on the fried products. Fried product wit egg yolk raised the acid value, absorbed volume and darkening of frying oil than the control but the peroxide value was the lowest. on the contrary, fried product without egg lowered the acid value, absorbed volume and darkening of frying oil than the control but the peroxide value was high, and the sensory evaluation scores were generally higher in fried product without egg than in the product with egg yolk. In genera, fired products with potato, or potato plus ascorbic acid or carrot lowered the acid value, peroxide value, absorbed volume, and the darkening of frying oil. fried potato 0products were also favorable to the taste panel.

• Journal of Food Hygiene and Safety
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• v.9 no.4
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• pp.213-220
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• 1994

Customary usage of oil at homes and rancidity of edible soybean oil by cooking frequency at homes and mass meal services were investigated. 80% of house wives bought the cooking oil by 1.8ι unit container and 70% of them read either the manufactured date or explanatory note for use. 85% of house wives kept oil in the storage case under sink or in the pantry chest, and 80% of oils were used once or twice and 20% used three times for cooking. Acid value(AV), iodine value(IV), peroxide value(POV), carbonyl value(CoV) and thiobarbituric acid value(TBAV) of fresh soybean oil were lower than standard level. In the rancidity by cooking frequency, the acid value, peroxide value, carbonyl value and thiobarbituric acid value increased significantly when oil was used once and iodine value decreased significantly when used once and twice at both mass meal services and homes. The level of the acid value, iodine value, carbonyl value and thiobarbituric acid value of oil used at mass meal services did not show significant difference from those of oil used at homes. But, the peroxide value of oil used thrice at mass meal services was significantly higher than those of homes.

• Journal of the Korean Home Economics Association
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• v.19 no.1
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• pp.33-37
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• 1981

The accelerating effect of sunlight on the rancidity of soybean oil and the efficacies of several anti-oxidants were measured. The result is as follows: 1. The ac야 value and peroxide value of soybean oil were 0.16 and 1, 72 respectively. 2. the peroxide value of soybean oil which was exposed to sunlight nine hours a day for six days was 134.3: 21 times of that which was not exposed to sunlight. 3. The peroxide value of the soybean oil with 0.02~0.06% BHA decreased a little, but not significantly. 4. The anti-rancidity effect of BHT was a little stronger than BHA. 5. The anti-rancidity effect of ascorbic acid alone was negligible. 6 The peroxide value of soybean oil with an anti-oxidant which comprised ascorbic acid, BHA and BHT decreased to one third of that which was not treated with anti-oxidant.

• Journal of the Korean Home Economics Association
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• v.33 no.6
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• pp.245-253
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• 1995

The purpose of this study was to investigate the fatty acid composition and the rancidity of commercial deep-fat fried foods in Kangreung. the 7 kinds of samples were purchased form snack corners in 3 markets at AM 10 and PM 6 o'clock. The acid value, peroxide value and TBA value of the deep-fat fried foods were determined and the fatty acid composition were analyzed. The range of acid value was 0.45∼1.79, that of peroxide value was 1.24∼8.64meq/㎏,and that of TBA value was 12∼140 in all samples. There was significant difference in most of all samples by purchasing time and kinds of samples. But there was not specific tendency by purchasing times in each sample. Most of the acid value, peroxide value and TBA value of the samples fried with meats or sea foods showed higher value than the that of samples fried with vegetables or seaweeds. The fatty acid composition of the total lipids in the deep-fat fried foods were similar to one another. The major fatty acids were linoleic acid(C18 : 2) , oleic acid(C18 : 1) in order of content. Minor fatty acids were palmitic acid(C16 :0), linolenic acid(C18 : 3), stearic acid (C18 : 0) in order of content. the P/S ratio was the range of 2.12/1∼4.71/1 and the that of the samples fried with meats was the highest among samples. so there was the same tendency in this result between the chemical properties(acid value, peroxide value, TBA Value) and fatty acid composition. As a result of acid value and peroxide value in this study, the commercial deep-fat fried foods in Kangreung was safety.

• Journal of the Korean Society of Food Culture
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• v.20 no.3
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• pp.352-359
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• 2005

The red ginseng powder was added to Yackwa dough as ratio to 0%, 2%, 4%, 6% and 8%, respectively to know effect of red ginseng powder on Yackwa quality and preservation. The expansion, color, texture and preference characters were investigated at 0,2 and 4 weeks, respectively. The peroxide and acid value were also measured. The 4% addition increased greatly expansion rate. In color test, L value lowed at addition of red ginseng powder and at long storage period. the b value lowed as the addition was increased, but a value was not affected by the addition of red ginseng powder. In mechanical texture test, addition of red ginseng powder had a tendency to show low cohessivness, springness, gumminess while hardness increased. The springness, brittleness and cohessivness decreased while hardness increased at long storage period. In sensory test, surface color, bitterness and red ginseng flavor were recognized strong by addition of red ginseng powder but oily taste, crispness, softness and overall preference were weak. The surface color and red ginseng flavor were strong at long storage period but sweetness, softness and overall preference decreased, respectively. The peroxide value increased at long storage period and decreased after 6 week. The 2% and 4% addition showed lower peroxide value compared to other treatment. The acid value increased at early storage period, but did not change after 4 weeks.

• Korean journal of food and cookery science
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• v.17 no.3
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• pp.229-236
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• 2001

This study was conducted in order to set the shelf life of Rice Yoogwa, Sesame Yoogwa and Yackwa to marketed in department store. It was investigated acid value, peroxide value, microbiological test and sensory evaluation for 50 days. Acid value of Rice Yoogwa, Sesame Yoogwa and Yackwa were not significantly different during storage period. Peroxide values of Rice Yoogwa and Yackwa were significantly increased after 30 days of storage but there was no different in Sesame Yoogwa. Fungus were appeared Sesame Yoogwa of A company, Rice Yoogwa and Yackwa of B company after 40 days of storage. In sensory evaluation, odor, taste, texture and overall acceptability after 40 days were significantly lower than 10 days of storage and rancid odor was gradually increased with preservation period in all materials. Correlation of acid value and peroxide value were positive throughout whole preservation period and rancid odor was increased. Odor, taste, texture and overall acceptability of Yoogwa and Yackwa were negative correlation with preservation period. In view of the above results, it came to the conclusion that shelf life of Yoogwa and Yackwa was 40 days.

• The Korean Journal of Food And Nutrition
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• v.31 no.5
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• pp.647-652
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• 2018

Extracts from bay leaves, Chongbaek (Allium fistulosum L.), Hutgae (Hovenia dulcis Thunb.) fruit, and green tea, using Soju (Korean alcohol, $30^{\circ}$) as a solvent were analyzed for their antioxidative properties. The eels were evenly coated with the extract concentration equivalent to 2% of their total weight and dried for 15 hours at $35^{\circ}C$ using an air blower. The DPPH radical scavenging effect, acid value and peroxide value of semi-dried eel, and linoleic acid peroxidation of eel oil were investigated. The highest level of DPPH radical scavenging was found in green tea extracts, followed by Hutgae fruit extract and bay leaves extract (p<0.05). The acid value and peroxide value of Hutgae fruit extracts coated eels refrigerated for 21 days were the lowest followed by the green tea extract coated eels. During the 20 days reaction period, all four kinds of extracts analyzed were found to effectively decrease linoleic acid peroxidation. Among them, Hutgae fruit and green tea extracts decreased the peroxide content of eel oil steadily and for a longer period when compared to other extracts. In conclusion, pre-application of Hutgae fruit and green tea extracts on eels before drying was found to be effective in delaying peroxidation in eels during the drying process and refrigeration.

• The Korean Journal of Food And Nutrition
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• v.35 no.2
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• pp.88-95
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• 2022

The antioxidant effects by pre-treatment of Hutgae fruit water and ethanol (30°, Soju) extract on refrigerated eels were analyzed. The antioxidant activities were measured through DPPH and ABTS scavenging effect, values of acidity, peroxide, carbonyl, and TBA. The peroxide prevention effects of linoleic acid and eel oil were also assessed. Regarding DPPH radical scavenging, Hutgae ethanol extract presented higher scavenging effects than vitamin C 5 mM solution (p<0.05). The eel's peroxidation degree was measured through 21 days of refrigeration after cleaning and immersion into the extract solution for one hour. Upon measuring the values of four different peroxide indicators, those of eels pre-treated with Hutgae extracts were lower than those of eels untreated. The POV of Hutgae ethanol extract, vitamin C 5 mM, and the control was 11.1, 11.3, 15.5 meq/kg, respectively. Hutgae ethanol extract showed higher antioxidant activities in TBA value, and carbonyl value than other samples. In linoleic acid or eel oil, Hutgae extract was as superiorly effective in preventing peroxide generation of refrigerated eels as vitamin C 10 mM solution. In conclusion, pre-application of Hutgae water and ethanol (30°, Soju) extract on eels was proved to be competent in stopping peroxidation of eel in refrigeration.

• Journal of the East Asian Society of Dietary Life
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• v.17 no.1
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• pp.81-88
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• 2007

The purpose of this study was to compare and evaluate the quality of beef jerky made with Korean beef meat, Korean beef cattle and imported beef meat from Austria and New Zealand. The beef jerky qualities were evaluated by sensory evaluation, measurement of crude lipid, fatty acid composition of lipid, and acid value and peroxide value, and of surface observation with a microscope. According to the preference test, whereas beef jerky made with Korean beef meat showed the highest score in color, glaze, palatability, and softness, while that of made with New Zealand beef meat did received the lowest score. The crude lipid content of jerky made with Korean and Austrian beef meat was higher than that of made with Korean cattle and New Zealand beef meat. Surface of jerky made with Korean and Austrian beef meat was gappier than that of made with Korean cattle and New Zealand beef meat, and the. The acid value of jerky made with Korean and Austrian beef meat was lower than that of made with Korean cattle and New Zealand beef meat. The peroxide value of jerky made with Korean cattle meat showed higher peroxide values from the initial storage time. However, the peroxide value whereas that of jerky made with Austrian beef meat was the lowest at initial storage time, it increased remarkably with storage time and showed the highest value after the 15th day of storage. We found that the change in quality of jerky made with Korean and Austrian beef meat was less than that those made of Korean cattle and New zealand beef meat. And it could be suggested that Korean cattle and New Zealand beef meat are not suitable in making jerky.