• Journal of Food Hygiene and Safety
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• v.18 no.1
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• pp.36-41
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• 2003

This study was performed to investigate the condition of frying at fried chicken shop, taste and thinking refer to fried chicken in the consumer. The acidification of frying oil was determined as acid value, peroxide value and fatty acid composition. The results were as follows: 1) Soybean oil was used for frying at a fried chicken shop at 170∼18$0^{\circ}C$ for 10∼ 15 min and replaced by every thirty cycles. 2) 76.2% of the consumer among answerers far the question thought that the oil of frying could be harmful to health. 3) The AV and POV were increased while chickens were fried after thirty cycles successively, but the values were lower than a standard level of fried-food. 4) The acidification of fried oil was in progress when chickens were fried for ten days by three times a day, but the value was low. 5) The AV of raw chicken was significantly increased as time goes, suggesting that a fresh chicken should be chosen.

• Korean journal of food and cookery science
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• v.14 no.2
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• pp.177-181
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• 1998

The changes of the physico-chemical characteristics of potato and chicken frying oil with frying number were examined. The changes in temperatures of frying oil during the potato flying were greater than that during the chicken frying. The weight loss of potato during deep frying was about 21.9% and about 12.3% for chicken. The acid values and conjugated dienoic acid values of the potato and chicken frying oils increased with increased frying number. Their values were greater in the chicken frying oil than in the potato frying oil. The peroxide values of frying oil did not change regularly as frying number increased. But iodine values of the frying oils decreased with increased frying number. Linoleic acid content of the frying oil decreased, whereas oleic acid content increased with frying number.

• Culinary science and hospitality research
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• v.17 no.4
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• pp.316-325
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• 2011

The property of deep frying oil is one of die important factors in fried food quality. The purpose of this study is to identify die quality of deep frying oil in continuous usages for 4 days by two types of fryers: traditional and modified fryers. After frying polk cutlets, die flying oil was kept not only for several physical analyses such as color, viscosity, and water content but also for quality analyses of flying oil such as free fatty acid, double bond changes and oxidative rancidity formation. The fried oil by a traditional flyer was significantly increased in die physical values of color and viscosity than that by a modified fryer. In die acid value, the fried oil by a traditional fryer was significantly increased in free fatty acid than that by a modified fryer while die iodine value was significantly decreased in die fried oil by a traditional fryer when compared to control oil and fried oil by a modified fryer. In die peroxide value as an indicator of primary oxidation products, die fried oil by both fryers was significantly increased till die second day but decreased in die value after die third day because of unstable hydroperoxides' decomposition. In die p-anicidine value as an indicator of secondary oxidation products, die fried oil in a traditional fryer was significantly increased in die value than that in a modified fry.

• Journal of the East Asian Society of Dietary Life
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• v.22 no.4
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• pp.527-534
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• 2012

This study investigated changes in the quality properties of deep frying oil and fried chickens according to frying number. Acid values of frying oil and fried chicken after frying 110 chickens were 2.27 and 1.90, respectively. The peroxide values of frying oil did not increase uniformly as frying number increased. Conjugated dienoic acid value of frying oil and fried chicken after frying 110 chickens were 0.70 and 0.44, respectively. Regarding the fatty acid composition after frying 110 chickens, linoleic and linolenic acids decreased, whereas palmitic, stearic, and oleic acids increased. Contents of trans fatty acids in frying oil and fried chicken after frying 110 chickens were 0.75% and 0.45%, respectively. Contents of benzo [a] pyrene in frying oil and fried chicken after frying 110 chickens were 2.20 and 2.19 ${\mu}g/kg$, respectively. The quality properties of frying oil and fried chickens significantly decreased after frying 60 chickens.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.2
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• pp.167-174
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• 1995

This experiment was carried out to investigate the major characters affecting the popping volume of popcorn. Tuygimok 1 (Kp1 ${\times}$ Kp2) and 8 popcorn hybrids' agronomic characters were tested to evaluate a certain extent how much they affect on the popping volume. Moisture con-tent was considered as the most important factor, but failed to evaluate the optimum moisture con-tent level in this experiment moisture range (12.2-14.4%) because popping volume increased as moisture content of kernels increased. The maximum popping volume was obtained at 55-60kg of kernel hardness, 80-90,um of pericarp thickness and 45-50% of S/H (Soft/Hard starch). But the Em/En(Embryo/Endosperm) ratio was negatively associated with the popping volume. Therefore the minimum popping volume was observed at the 10-11 % of Em/En ratio. Moisture content, hardness, pericarp thickness, Em/En and S/H ratio were selected as the appropriate variables for the maxi-mum popping volume using the stepwise forward regression method and the expecting popping volume was estimated by the multiple linear regression formular. The mean popping volume of ninepopcorn hybrids was about 29.2cm3/g.

• Journal of the Korean Applied Science and Technology
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• v.10 no.2
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• pp.7-10
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• 1993

This study was carried out to investigate the effect of silicone oil on preventing deterioration of oil in frying potatoes. The results obtained are summarized as follows: 1. Frying potatoes in oil, the oil added silicone oil slowly increased acid value, dielectric constant and decreased smoke point as compared with the oil without silicone oil. In the early stage of frying, there was on difference in deterioration degree of the frying oil between 1ppm and 10ppm addition of silicone all. But as frying time prolonged, the higher silicone oil was added. the more stable in deterioration of frying oil. 2. When silicone oil was added at the level of $1{\sim}10ppm$ into the oil for frying potatoes. it was possible to prevent deterioration of the frying oil.

• Korean journal of food and cookery science
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• v.16 no.4
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• pp.328-335
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• 2000

This study was investigated the effect of application methods of frying oil on the physicochemical properties of frying oil in the school foodservice. Frozen pork cutlet was fried for this study. The most frequent application methods of frying oil in school foodservice and treatments of this paper were as follows ; (A) use the frying oil (36ι) just one day(200ea.$\times$ 5times) (B) reuse the used oil(A method) once more adding 50%(18 ι) fresh oil after 3 or 5 or 7 days (C) reuse the used oil(A method) once more after 3 or 5 or 7 days. The major fatty acids of fresh oil were linoleic acid, oleic acid, palmitic acid, and linolenic acid in order to content. The viscosity of frying oil was increased gradually by increasing the number of frying times and storage period of frying oil after once used. Both redness and yellowness of frying oil showed similar trend to viscosity. As a result of this study, the application methods of frying oil in the school foodservice influenced on the physicochemical properties of frying oil, but acid and peroxide value were under the safety level of frying oil prescribed in the Health Social Affairs Ministry.

• Proceedings of the Korean Journal of Food and Nutrition Conference
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• 2000.12a
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• pp.56-56
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• 2000

대두유를 기초로한 튀김유에 capsicum, butter flavor, 규소수지를 각각 0.20, 0.15%(w/w) 및 10ppm 처리하여 가열안정성의 향상 및 육두향 약화에 효과가 있는 것으로 확인 되었다. 즉, capsicum과 규소수지를 병행처리한 튀김유는 185$\pm$2$^{\circ}C$의 온도조건 하에서 3시간 동안 연속적으로 열처리할 경우 AV 및 SP가 각각 무처리군의 0.385, 22$0^{\circ}C$에 비하여 크게 향상된 0.301, 232$^{\circ}C$를 나타내었다. 이러한 효과는 capsicum의 항산화 효과와 함께 소포제의 일종인 규소수지의 작용에 따라 가열처리에 따른 튀김유의 표면적 팽창을 방지하여 유리지방산 생성 및 연기발생을 억제한데 따른 효과인 것으로 판단 되었다. 또한. 0.15%(w/w)의 butter flavor 처리에 따라 튀김유 및 튀김물에서 발생하는 육두향 및 기름타는 냄새를 막아주는 효과가 인정되어 새로운 형태의 튀김유제품 생산이 가능할 것으로 기대 되었다.

• Journal of the East Asian Society of Dietary Life
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• v.21 no.5
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• pp.723-730
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• 2011

Soybean oil used to fry French fries, chicken nuggets, and donuts was exposed to high temperature at $180^{\circ}C$ for 72 h. The effects of frying foods on the thermooxidative stability of soybean oil were evaluated by determining the contents of free fatty acids, peroxides, total polar compounds, and conjugated dienoic acids, and by analyzing dielectric constant, refractive index, iodine value, smoke point, and fatty acid composition. The contents of free fatty acids, total polar compounds, conjugated dienoic acids, dielectric constant, and refractive index increased, whereas iodine value, smoke point, and U/S ratio of fatty acids composition decreased with frying time. All samples of frying oils after 72 h presented free fatty acid contents of below 2.0% and total polar compounds of below 25%, which were within the legal limits. However, peroxide values of frying oils were not directly correlated with frying time. The type of fried food affected the thermooxidative stability of the frying oils, with chicken nuggets being more stable in thermooxidation than French fries and donust. Among physiochemical indicators of frying oil quality, a rapid method including dielectric constant and refractive index can be used in quantity food production.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.2
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• pp.261-266
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• 2009

All of the subjects of the investigation (n=141) were schools that have food services under direct management. The number of students who get food services at the schools were $1,001{\sim}1,500$ students with 46.8% investigation. In school food services, fried foods were highly preferred and the biggest merits of fried foods were (in order of highest importance) 'improvement of food services satisfaction'> 'source of calories supply'> 'easiness of cooking process'. Service frequency of fried food were in the order of 'twice a week'> 'three times a week'> 'once a week', and for the factors to decide service frequency of fried food, 'preference leaning on fried food', and 'excessive fat intake' were the most considered. The most considered factors in the case of choosing fried food were 'preference' and 'calories and nutritional value'. For the cautious steps during the frying process, 'keeping after frying' was picked the most, and the reasons were 'lack of containers to keep in appropriate temperature and quality' and 'time consuming'. For preference and service frequency of ingredients in fried foods, 'chicken' and 'pork' were very high. As the result, it was analyzed that preference by ingredients matched service in school lunches by using a ranking test. Total cooking and processing time of fried foods required in school lunches were approximately $237{\pm}99$ minutes ${\sim}291{\pm}141$ minutes which showed total required time was about same no matter what ingredients were used. As the result of comparing and analyzing the processes, vegetables took less thawing and frying time, but the processing time for vegetables was more complicated since handling time before frying was longer compared to meat. In the important management process by the main groups of fried foods, the frying process was the most cautious cooking process in the category of meat or fish and shellfish used as ingredients. In addition, if vegetables were used as ingredients, storing it after frying was the process that needed the most care.