• Korean Journal of Human Ecology
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• v.22 no.3
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• pp.485-492
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• 2013

The temperature changes of dumpling(mandu) during cooking process were examined and the effects of time-temperature and/or time-size interactions on internal temperature were studied. Mandu was purchased from local markets and classified by its weight(small, medium, and large). Boiling, steaming, pan frying, and deep fat frying were adopted. Internal temperature was measured with a food thermometer in every one minute. The internal temperature of mandu increased over time in every cooking process(p<0.05). After three minutes the internal temperature of mandu in boiling, pan frying, and deep fat frying reached over at $74^{\circ}C$, which is high enough temperature to kill the harmful bacteria, but not in steaming. The internal temperature of mandu was significantly affected by cooking time, size, and both in boiling, steaming, and deep fat frying(p<0.05). There were significant differences between the internal and surface temperatures of mandu in the cooking processes except pan frying in three minutes(p<0.05). The results of this study indicate three minutes' cooking of the mandu by boiling, pan frying, and deep fat frying is safe enough to eat. However, longer steaming time is needed in order to reach safe temperature. This study also indicates the cooking time and size of mandu appear to be major factors in determining the internal temperature achieved at $74^{\circ}C$. More research is needed to check time to reach a safe temperature in the cooking process of mandu by steaming.

• Korean Journal of Food Science and Technology
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• v.23 no.2
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• pp.157-160
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• 1991

Copper constantan thermocouples connecting to a recording potentiometer were inserted at the center of the patties and the samples were fried. In general, the internal temperature of the patty samples increased approximately $11.1^{\circ}C$ after the samples were removed from the fryer. The desired internal temperature and maximum internal end-point temperature, at different frying temperatures, can be obtained by adjusting the frying time. The yields of the patties decreased as maximum internal end-point temperature increased or as frying time increased. The internal temperature and maximum internal end-point temperature of the patty samples at three frying temperatures were predicted using polynominal regression of a third-order model with one independent variable, frying time. Polynominal regression of a second-order model with maximum internal end-point temperature as the independent variable was used to predict frying yields at three frying temperatures.

• Journal of the East Asian Society of Dietary Life
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• v.27 no.3
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• pp.280-294
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• 2017

Premix frying powders were prepared by supplementation with 0%, 3%, 6%, 9%, or 12% egg white powder. The following quality characteristics of the fried batter were assessed: proximate composition and amino acid content of premix frying powder; viscosity and pick-up ratio of frying batter; moisture content, lipid content, color, texture and DPPH radical scavenging activity; and sensory evaluation items. Addition of egg white powder in place of wheat flour resulted in lower moisture content (p<0.01) and lower carbohydrate content (p<0.001), higher crude protein content (p<0.001), higher ash protein content (p<0.001), and higher amino acid content (p<0.01) in the premix frying powder. Lower viscosity and higher pick-up ratio (p<0.001) of the frying batter were observed. The resultant fritters had the higher moisture content and higher lipid content (p<0.001). They also showed the lighter color, and had lesser redness and yellowness (p<0.001). Considering texture, the fritters were harder, had higher fracturability and higher adhesiveness (p<0.001), lower springiness (p<0.001), were less chewy (p<0.01), and had lower cohesiveness (p<0.001). Examination of DPPH radical scavenging activity showed higher antioxidant activity (p<0.001) upon addition of egg white powder. Sensory evaluation of the fried batters showed the best outcomes for the group containing 6% white egg powder, in terms of appearance (p<0.05), flavor (p<0.001), taste (p<0.01), texture (p<0.01), and overall quality (p<0.001). Based on the results of this research, we postulate that the addition of 6% egg white powder to premix frying powder will not only improve customer preference and product quality but also enhance the nutrition and functionality of the product.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.6
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• pp.834-841
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• 2020

Laver Pyropia sp. is the most exported seafood in Korea and is one of the most consumed edible seaweeds. The export of laver has been centered on seasoned laver products; of note, laver snack products coupled with rice papers or glutinous rice paste are becoming more popular in Western countries. These laver snacks are manufactured using a deep frying process. Therefore, the frying conditions affect the physicochemical and sensory characteristics of fried laver snacks. In this study, we optimized the deep-frying conditions for laver snacks with gelatinized rice dough using a response surface methodology. The frying temperature (X1, 190-220℃) and frying time (X2, 10-30 sec) were selected as independent variables; the dependent variables were the overall acceptance (Y1, points), hardness (Y2, N), and oil content (Y3, %). The optimal values of the frying temperature (X1) and time (X2) as per the overall acceptance (Y1) were 208℃ and 23.1 sec, respectively. The predicted overall acceptance (Y1=8.0 points), hardness (Y2=98.74N), and oil content (Y3=27.69%), were similar to the experimental values under the optimal conditions. Overall, the acceptance was inversely proportional to hardness; the decrease in hardness caused an increase in the crispiness of the laver snacks.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.6
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• pp.941-947
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• 2013

To increase the consumption of frying ginseng, we investigated the physicochemical properties of frying ginseng and different edible oils processed through frying ginseng: soybean oil (SO), corn oil (CO), olive oil (OO), and grape seed oil (GO). We tested various parameters, including temperature (130, 160, 180, and $200^{\circ}C$), frying time (2.0, 2.5, 3.0, and 3.5 min), and frying amount (up to 30 times). The physicochemical properties of the fried ginseng and oils were evaluated for changes in acid value, peroxide value, free fatty acid content, acrylamide formation, color, and viscosity of oils. The acid value and peroxide value of the oils increased with frying temperature and amount. Saturated fatty acids increased and unsaturated fatty acids decreased with the amount of frying, but oleic acid in CO and GO and linoleic acid in OO increased. The concentration of acrylamide in fried ginseng increased as the frying temperature and amount increased and was the lowest in OO. The lightness and redness of the frying oil color decreased and its yellowness increased in SO and CO, but the lightness increased (redness and yellowness decreased) in OO. In particular, CO was significantly browned with increasing frying amounts. The viscosity of the frying oils increased with frying amount, with CO showing the lowest increases in viscosity of the oils. As a result, the optimal ginseng frying condition found was 2 min 30 sec at $180^{\circ}C$, regardless the type of oils.

• Culinary science and hospitality research
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• v.24 no.2
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• pp.79-86
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• 2018

The purpose of current study was to evaluate the oxidative stability of soybean oil after frying according to storage temperature. The soybean oil after 10 times deep fat frying with potato sticks (10% w/w of oil) were stored during 10 days at 30, 60 and $90^{\circ}C$ and chemical properties were determined. The acid value and peroxide value were the highest and the iodine value were the lowest when the oil stored at $90^{\circ}C$. Expecially, the production rate of peroxide was fast at over $60^{\circ}C$. According to the results, frying oil should not be stored for more than 6 days at $30^{\circ}C$ after use. Since the oil used had already produced unstable peroxides, oxidation could proceed relatively quickly even at low temperatures. Therefore, it is desirable to keep the used oil at a temperature as low as possible.

• 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.

• KSBB Journal
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• v.11 no.5
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• pp.572-576
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• 1996

Conditions for the culture of Pleurotus spp. mycelium using rancid frying oils were investigated. Among the six strains tested, Pleurotus ostreatus CBS 03 showed the greatest mycelial growth on fish paste and ramyon frying oil, and was used in this study. The optimum temperature and pH for mycelial growth were from 25 to $30^{\circ}C$ and pH 5.5 to 6.0, respectively. Tryptone for mycelial growth was better than any other nitrogen sources. The addition of $KH_2PO_4 and MgSO_4$ enhanced mycelial growth at 0.2 and 0.01% on fish frying oil, and at 0.1 and 0.03% on ramyon frying oil. Among the vitamins used, thiamine and nicotinic acid were the most effective ones.

• Journal of environmental and Sanitary engineering
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• v.4 no.1 s.6
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• pp.29-36
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• 1989

The purpose of this investigation was performed for chemical values related to rancidity of fat and oils extracted from deep-frying food in Seoul. The samples were collected according to kinds of fat and oils, sampling sites and food stuffs for frying. The results were as follows 1. The most used frying oils were rice bran oil $(37.0\%)$ and shortening $(29.6\%)$, followed by rapeseed oil $(14.8\%)$. 2. The chemical values related to rancidity of fat and oils extracted from deep-frying foods were the next on average. Acid value-1.42, peoxide value-39.82, dinitrophenyl hydrazine value-16.73 thiobarbituric acid value-0.263. However the highest value among oils was showed in rice bran oil and the lowest value was shortening. 3. For the classification of sampling sites, acid value and peroxide value of samples of the markets were found higher than them of environs of school and roadside, and the differences between them were significant (P> 0.01), while dinitrophenyl hydrazine value and thiobar bituric acid value were not showed the significant differences. 4. For the classification of foodstuffs for frying, there were not recognized significant differences among all kinds of them.

• Food Science of Animal Resources
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• v.40 no.5
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• pp.785-794
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• 2020

Food Codex regulations have set freshness limits for oils used to fry food, such as potato and fish products, and fried food itself; however, no such freshness limits have been set for meat products, such as sweet and sour pork. The freshness standard suggest that acid values (AVs) and peroxide values (POVs) for frying oil should be less than 2.5 and 50, respectively, whereas AVs and POVs for common fried food should be less than 5.0 and 60, respectively. Therefore, in this study, we investigate the effect of the number of frying cycles on oxidation-promoted changes in the oils used to fry sweet and sour pork and fried food itself during repeated frying over 10 d by determining their AVs and POVs, which were found to be highly correlated. Soybean, canola, palm, and pork lard oils could be reused approximately 37, 32, 58, and 87 times, respectively, to fry sweet and sour pork based on oil freshness, and 78, 78, 81, and 286 times, respectively, based on the freshness of fried food. Our data may help establish food-quality regulations for oils used to fry animal-based foods.