• Journal of the Korean Society of Food Science and Nutrition
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• v.18 no.3
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• pp.247-254
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• 1989

In deep-fat frying, the fats and oils are used over and over again, and moisture and air are mixed in to the hot oil. Many reports related to these fats and oils have been established that thermal and oxidative decomposition products and polymers formed under the conditions of deep fat frying are harmful to health. This work was carried out with 3 domestic frying oils and 6 used oils commercially, and that there were difficulties in finding a good definition between fresh oil and used oil with adding unheated oil. As starting materials, commercially used soybean oil and rapeseed oil already passed over induction period in the lipids oxidation standard. From the qualitative point of view, they were inferior to domestic frying oils. Free fatty acid and peroxide value of heated oils were increased gradually by the time pass whereas iodine value were decreased. After adding unheated oil to the heated oil, these values were restored to that of initial levels. On the other hand, content of polar components in the heated oil were directly related to the heating time. This result showed that polar compounds may be a clear indicator of used oils. Fatty acid composition in the used oils, unsaturated fatty acids such as linoleic and linolenic acid decreased while saturated fatty acid content increased with heating.

• 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$^{\circ}C$.

• Korean journal of food and cookery science
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• v.27 no.6
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• pp.671-680
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• 2011

In this study, frying mix was prepared containing 0.5, 1.0, 1.5 or 2.0% brown rice fiber(BRF). The samples along with a control were then compared regarding their quality characteristics, including pasting properties, spreadability, pick-up ratio, color, textural characteristics, moisture and oil contents, and sensory qualities, all to determine the optimal ratio of BRF. For the pasting properties of frying mix, the control group was evidenced by a significantly higher peak viscosity, through viscosity, and final viscosity than that observed in the BRF samples. Breakdown was the highest at the 1.0% addition level, and time to peak viscosity and pasting temperature were maximal with the 0.5% addition. There was no significant difference in setback among the experiments. Spreadability and pick-up ratio of frying batter were not significantly different among the samples. As the BRF content increased, the lightness, greenness decreased, whereas yellowness increased. The BRF samples presented significantly higher hardness of fried batter than the control group and there was no significant difference in crispiness among the samples. Moisture content of fried sweet potato decreased with increasing BRF and oil content was the maximum on the control group. In the sensory evaluation, appearance, color, flavor, savory taste, yellowishness, coating thickness, off-flavor, and oiliness were not significantly different among the fried sweet potato samples. Bindingness, crispiness, and chewiness were highest in the control samples but minimal at a addition level of 2.0%. The control group evidenced significantly higher overall acceptability than were observed in the BRF samples. In conclusion, the results demonstrated that 0.5~1.0% BRF may prove quite useful as a additive for frying mix in the preparation of fried sweet potato and may provide favorable textural and functional properties.

• Korean Journal of Food Science and Technology
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• v.50 no.1
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• pp.8-13
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• 2018

The textural and antioxidant properties, as well as the changes in functional constituents of shiitake mushrooms cooked by three different methods (boiling, steaming, and frying) were analyzed. The hardness of the mushrooms did not change significantly at the end time of cooking for each method. The antioxidant properties determined by measuring the free-radical scavenging activity and total phenolic content were the highest in the control (uncooked shiitake), and these properties were adversely affected after cooking, especially by boiling. Both the riboflavin and eritadenine contents were the highest in the control, but decreased upon cooking, in the following order: frying > steaming > boiling. The ergocalciferol content after frying was less than that in other samples. Although uncooked shiitake mushroom showed a higher concentration of functional constituents, it needs to be cooked adequately owing to its tough texture. If the hardness of the mushrooms cooked by different methods is the same, frying is considered the most acceptable method.

• Korean journal of food and cookery science
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• v.15 no.3
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• pp.264-271
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• 1999

This study was conducted to know the storage stability of Yackwa, a traditional Korean fried cookie, prepared by two different cooking methods; deep fat frying at 160$^{\circ}C$ for 8 min (DFF), and preheating Yackwa dough and then deep fat frying at 180$^{\circ}C$ for 2 min (MW/DFF). Soybean oil (SBO), hydrogenated soybean oil (HSBO) or hydrogenated palm oil (HPO) were used for frying Yackwa. Compared to Yackwa prepared by DFF, all MW/DFF Yackwa samples had low fat content and high moisture content. MW/DFF saved frying time 6 min compared with DFF. Non-hydrogenated soybean oil for frying fats was replaced with hydrogenated types of soybean oil and palm oil to improve the storage stability of Yackwa. To investigate the oxidation stability of Yackwa during the accelerated storage for 15 days at 60$^{\circ}C$, acid value, anisidine value, peroxide value and oxidation value of Yackwas were measured. Acid values of Yackwa made by MW/DFF were higher than those made by DFF through the whole storage periods, regardless of frying fats. Peroxide and anisidine values of Yackwa coated with syrup were much lower than those without syrup. MW/DFF cooking method, using hydrogenated soybean oil or hydrogenated palm oil for frying, showed lowering effects on peroxide value as well as anisidine value, resulting in improved oxidation stability of Yackwa during the storage. In sensory evaluation, the acceptability of MW/DFF Yackwa was higher than those of the commerical products. Yackwa prepared by MW/DFF cooking method using hydrogenated palm oil, showed the highest acceptability in color, taste and texture among the samples.

• Korean Journal of Food Science and Technology
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• v.49 no.5
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• pp.532-537
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• 2017

The purpose of this study was to examine the best cooking condition to decrease 4'-O-methylpyridonxine (MPN, ginkgotoxin) and increase the antioxidative effect. We also examined the change in color of ginkgo biloba seeds after different cooking methods and times. MPN content was decreased with an increase in the cooking time. For the reduction of MPN content, the most efficient cooking method was pan-frying. In particular, MPN content was largely reduced after 8 min of pan-frying. 1,1-Diphenyl-2-picrylhydrazyl radical scavenging activity and total flavonoid content were increased after 11 min of pan-frying and this level was maintained until 14 min. The total phenolic compound content was maintained for up to 30 min by steaming and 11 min by pan-frying. Therefore, the optimum condition was established by pan-frying from 8 to 11 min.

• The Korean Journal of Food And Nutrition
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• v.25 no.4
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• pp.1081-1085
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• 2012

This study was performed in order to determine the processing conditions (pre-drying at room temperature for 0 or 30 min, frying at $160^{\circ}C$ for 1 min or at $180^{\circ}C$ for 40 sec, and soaking for 0~24 h) of Sasambeong recorded in the "Sumunsasul". The Sasambeong was evaluated for crude lipid content, hardness, Hunter's color values, and sensory characteristics. After pre-drying at room temperature for 30 min, the crude lipid contents and hardness of Sasambeong were significantly increased. In addition, the crude lipid content and hardness of Sasambeong did not differ significantly according to the frying conditions. After pre-drying, the sensory characteristics of Sasambeong showed more improvement. The crude lipid content, hardness, Hunter's color values, and sensory characteristics of Sasambeong, which were prepared according to different soaking times (0, 6, 12, or 24 hr) were investigated. As soaking time increased, the crude lipid content and hardness of Sasambeong decreased with a range of 25.43~24.31% and 525.90~388.98 g, respectively. The sensory characteristics of Sasambeong showed no significant difference according to the soaking time. Overall, we think that the best processing conditions of Sasambeong were pre-drying at room temperature for 30 min and then frying at $160^{\circ}C$ for 1 min.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.4
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• pp.654-659
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• 1994

To elucidate the relationship between physical and chemical properties of frying vegetable oils, soybean oil and cottonseed oil were heated in air temperatures from $160^{\circ}C\;to\;220^{\circ}C$ for 60 hours. Acid value, carbonyl value, iodine value, viscosity and content of polymer were remarkably changed as higher heating temperature and/or longer heating time. Correlation coefficient of viscosity to acid value was 0.9843 for soybean oil and 0.9819 for cottonseed oil. In case of viscosity and carbonyl value, viscosity also showed good relationship to carbonyl value as 0.9779 for soybean oil and 0.9797 for cottonseed oil. And correlation coefficient of viscosity to iodine value of soybean oil was 0.9852 and cottonseed oil was 0.9948.

• Food Science and Preservation
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• v.8 no.3
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• pp.331-337
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• 2001

The oxidative stability of tallow heated was studied by different frying condition (temperature 130, 150, and 180$^{\circ}C$;heating time, each 10hours per day, total 240hrs). Changes of physicochemical parameters such as acid value, peroxide value, iodine value, dielectric constant, content of polar components and polymer, refractive index, smoke point, viscosity and color changes in tallow heated were also measured. Acid value, dielectric constant, refractive index, viscosity, and content of polar component and polymer increased as the tallow was heated longer, whereas iodine value and smoke point decreased and peroxide value was increased and decreased repeatedly. These parameters changed to a greater extent as the heating temperature went up. The color became darkened with the increase of red and yellow values during heating. The decree of coloration was proportional to heating temperature.

• Journal of the Korean Society of Food Culture
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• v.33 no.6
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• pp.473-488
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• 2018

The purpose of this study was to review literature on beef recipes, focusing on 20 recipe books published from the late 1800s to 1990s. A total of 119 beef dry-heat cooking were recorded. The most often used cooking were as follows: roasting 54 times, skewering 35 times, stir-frying18 times, pan-frying11 times and deep frying 1 time. The culinary book that the recipes was Hangukeumsik daegwan (1997). ribs, brisket, rump, bottom sirloin, sirloin and tenderloin were used but all beef cuts were marked as 'beef.' Thus, it impossible to figure out which beef cut was used in the recipe. Chili, green onion, egg, tofu and wheat flour were used together as, while soy sauce, salt, sugar, sesame oil, ground pepper, pear juice, honey, chopped green onion, chopped garlic, ginger juice, ground sesame used as. In addition, pine nuts or ground pine-nuts were often used for garnish.