• Preventive Nutrition and Food Science
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• v.11 no.3
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• pp.253-256
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• 2006

The purpose of this study was to develop a gas chromatographic (GC) method to analyze fatty acids in milk fat with a single injection. The single-injection GC method we developed for analyzing fatty acid composition can separate a wide range of fatty acid methyl esters from butyric acid to docosahexaenoic acid. It separated 6 isomers of 18:1 (cis-6, cis-9, cis-11, trans-6, trans-9 and trans-11), 4 isomers of 18:2 (cis-9-cis-12, trans-9-trans-12, cis-9-trans-12 and trans-9-cis-12), and 4 isomers of conjugated 18:2 (cis-9- trans-11, trans-9-cis-11, cis-10-trans-12 and trans-10-cis-12).

• Journal of Nutrition and Health
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• v.42 no.3
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• pp.291-299
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• 2009

This study was carried out to examine the proportion of fatty acids and contents of trans fatty acid in commercial processed foods in Jeon-Buk area. Contents of trans fatty acid in bakery products ranged from 0.2% to 1.0% per 100 g food. Especially garlic bread and pastry contained the highest amount. Popcorns contained trans fatty acid from 0.0% to 13.4%. Among them, instant popcorns for microwave contained the highest amount, while trans fatty acid was hardly detected in popcorns for theater. And trans fatty acid detected in popcorns was mostly in the form of 18 : 1 trans. The content of trans fatty acid in pizza was nearly 0.2%. Amounts of saturated fatty acid and unsaturated fatty acid were similar between each type of pizza and frozen pizza. Fritters such as fried chickens and vegetables contained trans fatty acid less than 0.2% per 100 g food.

• Food Science and Biotechnology
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• v.18 no.2
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• pp.350-355
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• 2009

In this research, fatty acid composition and trans fatty acids of 22 selected meat products produced by Turkish companies were analyzed by capillary gas liquid chromatography (GLC). Total fat contents of the meat products ranged from 11.60-42.50%. Salami had the lowest fat content 11.60% and sucuk (soudjuk) the highest 42.50%. Major fatty acids were C$_{16:0}$, C$_{18:0}$, trans C$_{18:1}$, cis C$_{18:1}$, and C$_{18:2}$ in the samples. Total unsaturated fatty acid contents have changed from 38.73 to 70.71% of total fatty acids, and sausage had the highest percentage among the samples. The majority of samples contain trans fatty acids and the level ranged from 2.28 to 7.95% of the total fatty acids. The highest amount of total trans fatty acids was determined in kavurma (Cavurmas) (7.95%), and total trans fatty acids of meat products such as pastrami contained more than 5% of the total fatty acids.

• Korean journal of food and cookery science
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• v.6 no.2
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• pp.37-50
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• 1990

The cause and the degree of the cis to trans isomerization were investigated about soybean oil (SBO), corngerm oil (CGO), cottonseed oil (CSO), margarine (MG) and shortening (ST). All samples treated with various conditions were analyzed to determine physicochemical characteristics (AV, POV, IV, RI), fatty acid composition, total trans fatty acid content and change of trans fatty acid composition by GLC, IR and HPLC. The results were obtained as follows; 1. Physicochemical constants were changed with a gentle slope according to incubating period at 40${\pm}$2$^{\circ}C$ and physicochemical constants of margarine and shortening were changed, significiantly. 2. The saturation degree in the unsaturated fatty acid composition determined by GLC gradually were increased during incubation and heating periodically. For palmitic-and stearic acid content at the samples stored in the incubator, the saturation degrees were gradually increased. But for the case of heat treatment, they were increased more rapidly than other fatty acids. 3. Total trans fatty acid contents in each samples were determined by GLC, IR and HPLC, the amount of trans fatty acids were measured with discrepancy. It was caused by deviation of analytical instruments, methods and the kinds of samples. Trans fatty acids were measured more definitly in IR more than GLC and HPLC. On the other hand, total trans fatty acid contents in average levels for SBO, CGO, CSO, MG and ST stored for 35 days and heated for 24 hours were 1.3%, 1.1%, 0.9%, 22.6% and 13.8%, and 3.6%, 3.0%, 2.8%, 41.2% and 20.8%, respectively.

• Journal of the Korean Society of Food Culture
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• v.23 no.4
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• pp.469-478
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• 2008

In this study, degree of rancidity and trans fatty acid formation were examined in fat and oils, including soybean oil (SB), canola oil (CA), corn germ oil (CO), olive oil (OL), palm oil (PO), and beef tallow (BT), during heating for 10-130 minutes at 160-200$^{\circ}C$. In order to determine the rancidity of the fat and oils, acid values (AV), iodine values (IV), viscosity, and color were measured. Changes in the amounts of fatty acids and the formation of trans fatty acids were measured using GC and HPLC. For all groups, AV increased, IV decreased, and coefficients of viscosity and color increased as the heating temperature and heating time increased, indicating there were positive correlations between the heating temperature and time and AV. In addition, all groups had similar amounts of trans fatty acids, with the exception of the beef tallow; however, its level only slightly increased with heating. The olive oil had the lowest trans fatty acid content and the lowest amount created by heating. The order of trans fatty acid amounts generated while heating was BT>PO>CO>CA>SB>OL. According to the study results, the deep frying temperature during cooking should be 160-180$^{\circ}C$ in order to reduce AV and the amount of trans fatty acids that are formed. In addition, it is better to remove beef tallow during cooking and avoid heating at high temperatures since it results in high levels of trans fatty acids. The correlation between the amount of trans fatty acids and AV was positive, while the correlation between the amount of trans fatty acids and IV was negative, indicating that AV and trans fatty acid levels increase while IV decreases as the deep frying temperature and time increase. From the results, it was found that reducing the deep frying temperature and time can lessen increases in AV and trans fatty acids, and decrease IV. Accordingly, to reduce AV and trans fatty acid formation, the ideal deep frying conditions would be to use olive oil or soybean oil rather than beef tallow or palm oil at a temperature of 160-180$^{\circ}C$.

• Journal of the Korean Society of Food Culture
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• v.23 no.3
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• pp.410-419
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• 2008

The objective of this study was to investigate the consumption pattern of snacks-containing trans-fatty acid in adolescents living in the Kwang-ju area of Korea, and to analyze the relevance toward their eating behaviors, body composition, nutrient intakes, and consumption frequency of snacks-containing trans fatty acid. A survey questionnaire was developed in order to investigate general environmental factors, eating behavior, nutritional knowledge, and the consumption frequency of snacks-containing trans fatty acid. A total of 312 middle school students were surveyed. The collection rate was 97% and ultimately 282 cases were analyzed. Anthropometric measurements, body composition data, and nutrient intakes were also collected. The consumption frequencies for snacks-containing trans-fatty acid were negatively correlated with food behavior scores (p<0.01) however, pocket money and snack intake frequency per day were positively correlated with consumption frequency. Also, snack consumption frequency had some correlation with the subjects' anthropometric measurements and body composition data such as total body water (p<0.01), body protein (p<0.01), body minerals (p<0.01), and skeletal muscle mass (p<0.01). Finally, the consumption frequency of snacks-containing trans fatty acid was significantly correlated with calcium intake (p<0.05), it also showed correlations with vitamin A, retinol, ${\beta}-carotene$, and folic acid intake, although statistical significance was not verified.

• Journal of Life Science
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• v.22 no.8
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• pp.1126-1131
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• 2012

The purpose of this study was to investigate the effects of trans-unsaturated fatty acid (TFA), saturated fatty acid (SFA) and general unsaturated fatty acid (USFA) on serum lipid levels in ICR mice. Male ICR 8-week-old mice were divided into six groups; the control group (C) fed with normal diet, the TFA-1 group fed with 10% trans-unsaturated fatty acid, the TFA-2 group fed with 30% trans-unsaturated fatty acid, the TFA-3 group fed with 50% trans-unsaturated fatty acid, the SFA group fed with 50% saturated fatty acid, and USFA group fed with 50% general unsaturated fatty acid. The serum total cholesterol of TFA-3 and SFA was higher than those of other fat groups and C. The serum triglyceride (TG) of TFA-3 and SFA showed the highest levels among all of diet groups. Also the serum HDL cholesterol levels of TFA-3 showed the lowest. LDL cholesterol and atherogenic indices (AI) were remarkedly increased in TFA-3 and SFA, as compared with other fat fed groups and C. Taken together with results, the TFA-3 group showed serum lipid levels similar to the SFA and different from the USFA. These results suggest that intake of high level of trans-unsaturated fatty acid increased serum triglyceride, LDL cholesterol and atherogenic indices, which may affect risk on serum lipid level for lipid metabolism syndrome.

• Korean Journal of Food Science and Technology
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• v.17 no.3
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• pp.219-222
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• 1985

Fatty acid patterns were determined for 11 and 19 brands of household margarines from the local markets in Korea in 1983 and 1984, respectively. Gas-liquid chromatographic analyses on OV-275 column showed that the average content of total trans fatty acids was 18% ranging from 6.2 to 35.5% for the margarines produced in 1983. The prototype of trans fatty acids was trans-octadecenoic acid. There was a small amount of c, t-or t, c-octadecadienoic, whereas there were practically no t, t-octadecadienoic acid. Trans fatty acids was increased in proportion to linoleic acid contents. For the margarines produced in 1984.. percentage of trans fatty acids tended to decrease, while that of linoleic acid was increased as compared with the corresponding values for the 1983 products. Thus, the P/S ratio was increased markedly in the soft type margarines produced in 1984. However, Korean margarines contained seemingly less linoleic acid than that contained in Japanese margarines.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.3
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• pp.399-405
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• 1996

The effects of stearic(18 : 0, SA), oleic(18 : 1 cis, OA) and elaidic acid(18 : 1 trans, EA) on the cell growth, contents of cellular lipids, and the fatty acid composition of cellular and medium lipids in Hep-G$_2$cells were evaluated. The cells were incubated in serum-free medium containing 25, 50, 100 and 200$\mu$M of a fatty acid combined with albumin for 2 days. The fatty acid concentration up to 100$\mu$M showed the normal growth, but the cell growth decreased in the presence of 200$\mu$M fatty acid. The treatment of cells with 100$\mu$M of a fatty acid for two days significantly(p<0.05) increased the cellular triglyceride(TG) content in all fatty acid groups compared to control, but TG contents was not significantly different among all treatment group, but total cholesterol(TC) was the highest level in EA group. The level of free cholesterol(FC) and cholesteryl ester(CE) was similar to those of TC in all fatty acid treated group. The cellular phospholipid(PL) contents were similar between the control and all fatty acid groups. The treatment of cells with SA has no notable effects on the fatty acid composition of TG, CE and PL. The OA treatment caused significant increases in CE(51.2%) and PL(29.8%), but not in TG. The EA treatment resulted in 10.1, 10.7 and 7.8% of $C_{18:1\;trans}$ content in cellular TG, CE, and PL. The TG, CE and PL of medium were relatively similar between SA and OA groups. In EA treated group, TG, CE and PL of medium contained 17.0%, 0.7% and 5.6% of $C_{18:1\;trans}$, respectively.

• Korean Journal of Agricultural Science
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• v.36 no.2
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• pp.211-217
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• 2009

Total fatty acid compositions, total content of crude fat, saturated, unsaturated and trans fatty acid content were studied in children's favorite foods such as hot dog, chicken popcorn, fried potato, snack and cookies, and imported biscuit. The samples were obtained from various stores in Daejeon. After fat extraction, methylation was carried out to analyze the fatty acid compositions by gas chromatography. The results showed that content of the trans fatty acid per 100 g of the hot dog, chicken popcorn, fried potato, snack and cookies, and imported biscuit were 0.02~0.03 g, 0.05~0.08 g, 0.02~0.05 g, 0.02~0.27 g, and 0.05~0.83 g, respectively. The highest content of saturated fatty acid (66.24%) was observed in the imported biscuit among the 20 analyzed samples.