• Korean journal of food and cookery science
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• v.17 no.5
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• pp.478-482
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• 2001

This experiment was carried out to clarify the effect of frying temperature and gelatinization method on the quality of popped rice for Salyeotgangjung. Frying at 220$^{\circ}C$ or 230$^{\circ}C$ gave a good expansion and score of sensory evaluation. But the frying oil began to smoke at 230$^{\circ}C$. There was no significant difference in the quality of popped rices between the treatments of minimum gelatinization after washing rice and moderate gelatinization after soaking for 80 minutes at 30$^{\circ}C$. In conclusion, frying washed rice with minimum gelatinization at 220$^{\circ}C$ would be considered as the best method for making Salyeotganagjung.

• The Korean Journal of Food And Nutrition
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• v.7 no.4
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• pp.318-322
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• 1994

Aluminium alloy, comprising water, silicone manganese and porous aluminium carrier added into soybean oil in order to investigated its effect on polar lipid content, polymer content, conjugated dienoic acid and free fatty acid value during deep-fat frying at 185$^{\circ}C$. Increase rates of polar lipid and polymer content of the frying ell were reduced about one thirds of the oil without aluminium alloy during deep-fat frying. The aluminium alloy, however, have no significantly effect to inhibit the increase of conjugated dienoic acid and free fatty acid value. Treatment of the frying oil with aluminium alloy was found to be able to inhibit polymer and polar lipid formation.

• 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.

• Korean journal of food and cookery science
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• v.18 no.3
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• pp.340-348
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• 2002

Changes in the physicochemical properties of frying oil after single or repeated use in foodservice establishments were studied. The experiment was designed to simulate the practical frying practice based on a survey from the dieticians in the food service establishments. Used oils came from the single frying of mackerel and the sequential frying of 1) potato and mackerel, 2) battered pork and mackerel, and 3) potato, battered pork, and mackerel. The used oil samples were analyzed and compared with the fresh one. Oil quality parameters such as acid value, peroxide value, thiobarbituric acid value, iodine value, viscosity, and color were measured at each step of deep-fat frying. The physicochemical properties of the frying oils have been more or less affected by the frying conditions. However, the used oils resulted from the experimental trials were within the range of acceptance as indicated by the acid and peroxide values.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.2
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• pp.181-189
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• 2008

In this study, changes in total trans fatty acid (tFA) and fat contents were determined in soybean oil, shortening, and olive oil after potato sticks were fried 30 consecutive times, respectively. Prior to frying, the potato sticks contained 3.8% fat, with 43.2% tFAs, After the first frying in soybean oil, the total tFA content of the potato sticks sharply decreased to 3.2%, and then it gradually increased to 8.1 % after 30 consecutive times of frying. However, the total fat content of the potato sticks, fried in soybean oil increased to 15.2% after the first frying and thereafter it decreased to 9.75% with 30 repeated episodes of frying. When the potato sticks were fried in olive oil, similar changes in tFA and fat contents were shown; while such changes were not observed when shortening was used. After 30 consecutive frying events, the tFA contents in the soybean oil and olive oil increased to 4.15 and 5.75%, respectively; however, such an increase was not observed in the shortening. One can assume that most of the tFAs in the fried oils were from the potato sticks, which contained relatively high tFA content during the repeated deep-frying process.

• Journal of the Korean Dietetic Association
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• v.4 no.1
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• pp.99-108
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• 1998

The purpose of this study was to investigate the effect of frying methods of chickens ; deep-fat frying with raw chickens(A), with pre-cooked chickens(B) on the physicochemical properties of frying oil and fried chickens in the school foodservice. Acid, peroxide and TBA value of frying oil were significantly increased by increasing the number of frying times and those of method A were higher than those of method B. On the contrary, Iodine value was decreased significantly with increasing the number of frying times but there is no significant difference between method A and B. In fatty acids, the content of saturated fatty acid increased while that of unsaturated fatty acid decreased as the frying times increased. Also viscosity, yellowness and redness increased significantly by increasing the number of frying times. The content of vitamin $B_1 $, of fried chicken by the frying methods was not significantly different, but vitamin $B_2 $the method A was higher than by the method B. Ca, P, Na, K and Fe contents of fried chickens by the method A were higher than those by the method B.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.1
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• pp.121-125
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• 1998

The effects of various cooking methods (blanching, microwave heating, and deep-fat frying) on biologically active components of Angelica keiskei were determined by HPLC. Cynharoside, the biologically active component of Angelica keiskei leaves was 4.82%, which was rapidly decreased by blanching, showing 3.79%, 2.59% and 1.74% at 1 min, 2min and 3min, respectively. Microwave heating also decreased the cynaroside contents slowly by 2 min and rapidly by 3min, respectively. Microwave heating also decreased the cynaroside contents slowly by 2min and rapidly by 3 min, showing 4.25% at 1 min, 3.38% at 2 min, and 1.49% at 3 min. Among the cooking methods tested, deep-fat frying was shown to preserve the cynaroside most. Only 3.90% of cynaroside was lost by 5 min frying. The decrease in cynaroside in each cooking method was supposed to be due to the conversion of cynarside, a glycoside of flavonoid, into luteolin through lysis of glucose at C-7 position on cynaroside.

• 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.

• 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.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.12
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• pp.1784-1791
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• 2016

Garlic was subjected to eight different cooking methods (raw, boiling, steaming, microwave cooking, deep-frying, oven-roasting, pan-frying, and pan-roasting) utilized for typical Korean cuisine. Garlic was analyzed for antioxidant activities and physicochemical properties to elucidate effects of cooking. Garlic cooked at higher temperatures showed significantly lower lightness and higher yellowness (P<0.001). In particular, deep-frying and pan-frying resulted in lowest lightness and soluble solid content, indicating that non-enzymatic browning reactions were more facilitated. Compared with raw garlic, all cooked garlic tended to have lower thiosulfinates, presumably due to decomposition into polysulfides and/or leaching into cooking water and oil. Microwave cooking retained organic acids, total reducing capacity, and flavonoids, which can be attributed to low microwave intensity and shorter cooking time under which heat-labile bioactive components might have undergone less decomposition. Cooking significantly increased metal-chelating activity (P<0.001). In addition, oven-roasting and pan-roasting enhanced total reducing capacity and flavonoid content, indicating that thermal treatments increased the extractability of bioactive components from garlic. However, boiling, deep-frying, and pan-frying, in which garlic is in contact directly with a hot cooking medium, reduced antioxidant activities. Deep-frying resulted in largest reduction in DPPH radical scavenging activity of garlic, which correlated well with reduction of total reducing capacity and flavonoid content. The results show that the antioxidant activity of garlic could be affected by cooking method, particularly heat intensity and/or direct contact of the cooking medium.