• Toxicological Research
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• 제31권3호
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• pp.307-312
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• 2015

Trans fat is a unsaturated fatty acid with trans configuration and separated double bonds. Analytical methods have been introduced to analyze trans fat content in foods including infrared (IR) spectroscopy, gas chromatography (GC), Fourier transform-infrared (FT-IR) spectroscopy, reverses-phase silver ion high performance liquid chromatography, and silver nitrate thin layer chromatography. Currently, FT-IR spectroscopy and GC are mostly used methods. Trans fat content in 6 vegetable oils were analyzed and processing effects including baking, stir-frying, pan-frying, and frying on the formation of trans fat in corn oil was evaluated by GC. Among tested vegetable oils, corn oil has 0.25 g trans fat/100 g, whereas other oils including rapeseed, soybean, olive, perilla, and sesame oils did not have detectable amount of trans fat content. Among cooking methods, stir-frying increased trans fat in corn oil whereas baking, pan-frying, and frying procedures did not make changes in trans fat content compared to untreated corn oils. However, the trans fat content was so low and food label can be declared as '0' trans based on the regulation of Ministry of Food ad Drug Safety (MFDS) (< 2 g/100 g edible oil).

• 한국분무공학회지
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• 제16권1호
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• pp.15-26
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• 2011

In this article, spray characteristics in CI engines fuelled with vegetable oils and its derivatives will be reviewed. Of edible vegetable oils, soybean oil and rapeseed oil were mainly investigated. Of inedible vegetable oils, jatropha oil and used frying oil were main concern on the research on the spray characteristics in CI engine. Spray angle and spray penetration were mainly examined among the macroscopic spray characteristics and Sauter mean diameter was only investigated among the microscopic spray characteristics. There exist six different definitions of spray angle which should be examined. Neat vegetable oil and biodiesel fuels show smaller spray angle than diesel fuel. Biodiesel fuel and vegetable oils and its blend have a longer spray penetration than diesel fuel. However, biodiesel blends with diesel shows the similar spray penetration with diesel fuel. SMDs in the biodiesel spray, vegetable oils and its blends spray are higher than that in the diesel spray.

• 한국식품조리과학회지
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• 제28권3호
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• pp.265-273
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• 2012

The purpose of this study was to determine the effects of the duration of frying and storage periods on physicochemical characteristics of various oils using at home. The materials used for the study consisted of four kinds of vegetable oils: soybean, canola, extra virgin olive and pure olive oils, and shortening. Chicken breasts were fried in oils heated at $180^{\circ}C$. The oils were stored with or without filtering and reused 3 times, during the 10 day period. The extra virgin and pure olive oils showed higher acid, peroxide value and yellowness than the other oils (p<0.05), but soybean oil showed the highest increase in acid, peroxide value and yellowness with reusing and storage. In sensory evaluation, the chicken breast fried with soybean oils remarkably decreased the overall acceptance. These results suggested that all frying oils are available because acid and peroxide values of the oils are lower than the standard level. However, reusing soybean oil should be noted with caution in that it is very easy to reduce rancidity, and extra virgin olive oil is not appropriate for frying.

• 한국식품영양과학회지
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• 제23권4호
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• pp.654-659
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• 1994

대두유와 면실유를 $160^{\circ}C,\;180^{\circ}C,\;200^{\circ}C\;및\;220^{\circ}C$에서 60시간 연속 가열하면서 이 때 일어나는 물리화학적 특성변화를 살펴보고 이들 간의 상관관계를 조사하였다. 가열시간이 경과함에 따라 산가, 카르보닐가, 요오드가, 점도, 중합체 함량은 증가하였고, 요오드가는 감소하였으며, 가열온도 $180^{\circ}C$ 이하에서는 이들의 변화가 낮았고, $200^{\circ}C$ 이상에서는 전체적으로 높게 나타났다. 점도와 산가 변화의 상관도는 대두유 0.9843, 면실유 0.9819이었고, 점도와 카르보닐가의 변화에서는 대두유 0.9779, 면실유 0.9797이었다. 점도와 요오드가의 변화에서는 대두유 0.9852, 면실유 0.9948로 나타났다. 이상의 결과는 튀김유의 가열산화에 있어서 점도의 변화를 측정함으로써 산가, 카르보닐가 및 요오드가의 변화를 비교적 정확하고 빠르게 예측할 수 있음을 시사하고 있다고 사료된다.

• 한국식품영양학회지
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• 제10권4호
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• pp.564-573
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• 1997

유지류는 산화에 의해 품질이 저하되며 이를 방지하기 위해 항산화제를 첨가하는 방법이 널리 이용되어 왔다. 그러나 현재까지 많이 이용되어온 tocopherol과 BHA는 상온에서는 높은 항산화 효과가 있지만 튀김 식품과 같이 18$0^{\circ}C$이사의 고온처리가 필요한 경우에는 열안정성이 매우 낮아 이들 항상화제들의 대부분 분해되거나 산화방지 능력을 상실한다. 식물체에서 안정한 자류 라디칼을 형성할 수 있는 구조를 갖는 스테롤, 즉 곁사슬에 에틸리덴기를 갖는 citrostadienol, $\Delta$5-avenasterol과 fucosterol이 고온에서 안정한 항산화 효과가 있다고 보고되었으며 그 중에서 $\Delta$5-avenasterol 이 고온에서 가장 높은 항산화 효과가 있다고 한다. 다라서 식품의 기호성과 저장성을 높이기 위하여 고온에서 안정성을 갖는 천연 항산화제의 개발이 필요하므로 문헌 고찰을 하여 정리하였다.

• 한국응용과학기술학회지
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• 제9권1호
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• pp.47-54
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• 1992

The natural antioxidant such as e-tocopherol and synthetic antioxidant BHT were used to compare antioxidative effects of those antioxidants from the physico-chemical properties and fatty acid composition changes in the soybean oil due to number of frying. The composition of frying oil were consisted of a group(Fresh oil), B gorup(Fresh oil added with 0.05% ${\alpha}$-tocopherol), C group(Fresh oil added with 0.2% ${\alpha}$-tocopherol), D group(Fresh oil added with 0.1% BHT), E group(Tocopherol removed oil from oil by active alumina column chromatography The results obtained were as follws : 1. The color was determined by the Lovibond colorimeter color intensity increased number of frying oil. 2, The acid value, TBA value and Carbonyl value were increased number of frying oil. 3. Natural antioxidants less effective than BHT but effect of ${\alpha}$-tocopherol was very similar to that of BHT. 4. The order of antioxidative effect was 0.1% BHT, 0.2% ${\alpha}$-tocopherol, 0.05% ${\alpha}$-tocopherol, fresh oil, tocopherol remove oil.

• Preventive Nutrition and Food Science
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• 제7권3호
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• pp.255-260
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• 2002

Yukwa is a popular Korean traditional fried rice snack. The high fat content and porous structure of Yukwa cause it to rapidly become rancid, presenting difficult challenges for commercial distribution. In this study, an-tioxidant activities of green tea extracts (GTE) were evaluated in Yukwa fried in soybean oil (SBO), rice bran oil (RBO) and winterized rice bran oil (WRBO) during storage at 4$0^{\circ}C$ for 12 weeks. Lipid oxidation of Yukwa was determined by acid value (AV), peroxide value (POV), p-anisidine value(AnV), totox value and sensory evaluation. The addition of GTE to the oils reduced the increases in AV, POV, AnV, and totox. Totox increased most vapidly in Yukwa fried in SBO, fellowed by RBO>WRBO>SBO+200 ppm GTE>RBO+200 ppm GTE > WRBO + 200 ppm GTE (p<0.05). Sensory evaluation revealed that the addition of 200 ppm GTE delays rancidity in Yukwa by 7~8 weeks; providing compelling evidence that GTE is an effective antioxidant for Yukwa.

• 한국식품조리과학회지
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• 제23권6호
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• pp.1015-1024
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• 2007

Trans-fatty acids (TFAs) are defined as the sum of all unsaturated fatty acids that contain one or more non-conjugated double bonds in a trans configuration. Dietary trans- fatty acids originate from commercially hydrogenated oils and from dairy and meat fats. From the perspective of the food industry, partially hydrogenated vegetable oils are attractive because of their long shelf life, stability during deep-frying, and semisolidity, which can be customized to enhance the palatability of baked goods and fried foods. Although no definite differences have been documented so far between the metabolic and health effects of industrial and ruminant TFAs, the intake of industrially produced TFA has declined, and in Europe, the majority of TFAs are of ruminant origin. Due to the scientific evidence associating TFA intake with increased risk of coronary heart disease (CDH), the Korea Food and Drug Administration (KFDA) issued a final rule that requires the amount of trans fat present in foods to be declared on the nutrition label, by December 1, 2007. In addition, many food manufacturers who use partially hydrogenated oils in their products have developed, or are considering ways, to reduce or eliminate trans-fatty acids from certain food products.

• Asian Pacific Journal of Cancer Prevention
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• 제15권21호
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• pp.9543-9547
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• 2014

Background: The aim of this study was to investigate demographic features, dietary habits, and some possible risk factors for being susceptible to breast cancer in Iranian women. Materials and Methods: A study of dietary habits and breast cancer was conducted among 53 Iranian women with histological confirmed disease and 40 matched controls. A dietary habits questionnaire was used to evaluate the pattern of selected food intakes. The risk of cancer was analyzed after adjustment for confounding factors. Age, weight, body mass index (BMI), waist circumference, educational status, parity, lactation, marital status, menopause, history of estrogen therapy, and family history of breast disease or cancer were assessed among participants. Special attention was given to the relationship between consumption of high fat meat, milk, yogurt and cheese as well use of frying oils for frying foods, use of olive/liquid oils for cooking, removing fat from meat and poultry, removing chicken skin and not use of mayonnaise as salad dressing and the risk of breast cancer. Moreover, salad, vegetable and fruit consumption, and eating outdoors owere investigated. Results: Our results revealed significant lower education and higher BMI and waist circumference levels in patients with breast cancer. There was significantly increased breast cancer risk in overweight women in comparison with normal weight (OR=2.91, 95%CI 1.24 to 6.82). High intake of fat dairy products including milk and cheese was found to be a statistically significant factor for increasing breast cancer risk in models adjusting for age, BMI and education. Use of olive/liquid oils for cooking and avoidance of mayonnaise as salad dressing are related to lower risk of breast cancer. The frequency of vegetable and fruit consumption was significantly lower in patients with breast cancer compared to healthy women. Conclusions: Dietary habits might be risk factors for breast cancer among Iranian women. Adoption of a prudent diet could be an appropriate strategy for preventing breast cancer.

• 한국식품과학회지
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• 제34권5호
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• pp.905-910
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• 2002

한국인이 상용하는 식물성 유지로부터 n-3 지방산과 n-6 지방산 산화의 독성 산물인 4-hydroxy-2-hexenal(HHE)과 4-hydroxy-2-nonenal(HNE)를 높은 감도로 동시 정량 하기 위하여 GC/MS/SIM(m/z = 157)을 이용하여 정량 하고 노출량을 추정하였다. 한국인이 섭취하는 식물성 유지의 98%를 차지하는 4종류의 유지로부터 4-hydroxy-2-alkenals의 총 노출량은 $2.7\;{\mu}g/day$로 나타났고, 시장에서 수거한 튀김 기름의 경우에는 상온에서 보관한 유지류에 비해 높은 양의 HHE와 HNE가 검출되었다. 튀김 과정 중에 형성된 4-hydroxy-2-alkenals는 튀김 음식으로 이행될 가능성이 있으므로, 튀김 음식을 자주 섭취하는 집단은 4-hydroxy-2-alkenals에 대한 노출량이 더 높을 것으로 사료된다. n-3와 n-6 지방산의 생리 활성에 대한 보고로 인하여 이들 고도 불포화 지방산의 섭취가 증가하고 있으므로, 불포화 지방산을 다량 함유하고 있는 식품으로부터 n-3와 n-6 지방산의 특이적 산화 지표인 4-hydroxy-2-hexenal과 4-hydroxy-2-nonenal을 동시 정량 하여 식품 품질 및 안전성 평가를 하는 것은 바람직하다고 생각된다. 본 실험에서 보여 준, 상용 식물성 유지의 4-hydroxy-2-alkenals 함량에 관한 데이터는 식품을 통해 노출된 4-hydroxy-2-alkenals가 인체에 미치는 생리적 효과를 평가하기 위한 앞으로의 연구에 중요한 정보를 제공할 것이다.