• Journal of Environmental Science International
• /
• v.25 no.11
• /
• pp.1459-1466
• /
• 2016

In this study, the concentrations of polycyclic aromatic hydrocarbons (PAHs) were investigated in meat process food and for cooking methods (pan-frying and charcoal fire). The methodology involved liquid-liquid extraction, silica gel cartridge clean-up and determination by gas chromatography/mass spectrometry (GC/MS). The recovery of 17 PAHs spiked into these samples ranged from 66.6 % to 98.0% and the coefficient of variation was less than 10%, but that of dibenz(a,h)anthracene was 16.39%. The mean concentration of total PAHs in processed samples was ND~7.2 ng/g, whereas that pan-fried and charcoal-fired samples were ND~22.1 ng/g and, 12.7~367.8 ng/g, respectively. Therefore, the concentrations of total PAHs in cooked samples were higher than in original samples and charcoal-fired samples had the highest total PAH levels.

• Journal of the East Asian Society of Dietary Life
• /
• v.8 no.4
• /
• pp.536-553
• /
• 1998

Korea supposed the place of origin of soybean. Although it is speculated that it was edible in the era of the Three Kingdoms(A.D. 5-9C), there is no documentary evidence. The first record about the edibility of tofu was written down in the Goryeo dynasty, and there was several documents that tofu was exported to China and Japan in the Chosun dynasty due to excellent manufacture skills for tofu. Tofu has been a good source of protein as a food for the common people, though there were not many traditional kinds. Especially, tofu has been an important vegetarian foodstuff in a Buddist temple, and has been used for vegetable soup and skewered greens necessary for the sacrificial rites of the humbler class as well as of the royal court. We frequently made sliced raw tofu and fried tofu, and it was used for broil, stew, and casserole as well as stuffing. In addition, tofu and its bean-curd dregs were applied of making soy. In China it is assumed that tofu has been eatable since the time of the Han(AD. 1C). Chinese tofu and its products are various and generally 20 different varieties are used. There are many dishes applied of tofu. salted and plain tofu were used as Chinese appetizer dishes. Plain, salted, skinned or deep-fried tofu was stir-fried in an hot oiled pan with vegetables, meats and fishes. Additionally, there are a variety of tofu dishes utilized stewing, frying, steaming, and soup cookeries. Tofu first appeared in the era of the Nara(8C) of Japan and was come into wide use in the era of the Aedo(Tokyo). In Japan tofu and its products are various and introduced in Shojin cookeries prevalent in the Buddist temples. It is especially noticeable that frozen or skinned tofu was used for these. Japanese tofu cooking is more delicate than Korean and Chinese ones, and Japanese people do not use oil. Instead, they in general utilize steaming and broiling cookeries. In the western countries the history of tofu edibility is short. However, their practical application of tofu in the dietary life is very positive.

• Journal of the East Asian Society of Dietary Life
• /
• v.24 no.1
• /
• pp.143-155
• /
• 2014

The purpose of this study was to analyze adaptation for Korean foods and satisfaction for university foodservice by nationality and residence period of Chinese and Japanese university students in Daejeon, Republic of Korea. Among 330 questionnaires distributed to Chinese and Japanese students, 294 complete questionnaires (89.1%) were analyzed. The questionnaire included two 5-point scales for measuring levels adaptation of for Korean food and satisfaction with university foodservice, respectively. Japanese students' level of adaptation for Korean food (3.16) was significantly higher than that of Chinese students (2.96). As the length of residence in Korea increased, the frequency of using university lunch service per week significantly decreased. The main factor when selecting a menu item was food taste (39.8%, 22.8%) in both Chinese and Japanese students, whereas the next main factor was preference (16.4%) in Chinese students and nutrition (18.7%) in Japanese students. The preferred cooking methods for meat were stir-frying (31.6%) and roasting (25.9%). For fish, Chinese students preferred braising (32.7%), whereas Japanese students preferred roasting (26.8%). Both Chinese and Japanese students preferred sukchae (45.6%, 43.1%) for vegetables. Factor analysis grouped 17 items measuring university foodservice into four factors, 'sanitation & employee service', 'physical environment', 'food' and 'customized menu & information' and the mean scores were 3.56, 3.30, 3.20 and 3.00, respectively. Chinese students were significantly more satisfied than Japanese students with the 'physical environment', 'sanitation & employee service' and 'customized menu & information'. These results suggest that efforts such as developing a greater variety of menu items with mild tastes and somewhat less flavor, applying preferred cooking methods, offering special menus for foreign students, providing nutrition information on menus, and offering a description of menu items in the foreign languages could improve Chinese and Japanese students' levels of satisfaction with university foodservice.

• Food Science and Preservation
• /
• v.8 no.3
• /
• pp.338-344
• /
• 2001

The oxidative stability of cholesterol in tallow heated at different frying temperatures (130$\^{C}$, 150$\^{C}$, and 180$\^{C}$) was studied by identifying cholesterol oxides by thin layer chromatography(TLC). And fatty acid compositions in tallow heated were also measured and compared with cholesterol oxides. Unsaturated fatty acid contents slightly decreased as the heating time increased, whereas saturated fatty acid contents increased This phenomenon became excessive especially by heating to higher temperature. It was found that RF value and spot color of the nonsaponifiable lipids from tallow heated on TLC analysis accorded with the synthetic cholesterol oxides in this experiment. Four kinds of cholesterol oxides were detected in tallow heated for 24 hours at three different temperatures. The oxides were identified as 7-$\alpha$-hydroxycholesterol, 7-$\beta$-hydroxycholesterol, 7-ketocholesterol and cholesterol epoxide. It was found that there was a little difference in oxidative pattern of cholesterol between several heating temperatures.

• Journal of the Korean Society of Food Culture
• /
• v.10 no.3
• /
• pp.185-200
• /
• 1995

In this survey, we investigated the way of thinking about meal management of housewives including the sincerity to meal preparation, the eating practices and cronic degenerative diseases related dietary behaviors, and studied the effects of above factors on the real food intakes. We also investigated the trends of health-foods and nutrient supplements usage. The results obtained from 506 housewives in Seoul were summarized as follows. Although our subjects prepared their meals habitually without special concern, they did not prefer the use of convenient foods. The food prefrence of housewivess who had more child and refered higher life status was similar with other family members. The dietary attitudes were good in large family, the higher income and the more child group. The highly educated group skipped breakfast more frequently. The mealmanagers with better education career and good living status considered for the restriction of salty foods, sweet foods, animal fats and pungent foods, and for the nutritionally balanced diet. The high income group showed great concerns about weight gain at meal times. The nutritional qualities expressed by the frequency of food group intakes were high in the better educated and living status groups, and their eating frequencies of animal protein foods and calcium sources were significantly high. Mealmanagers who had no job intaked vegetable oils through frying foods frequently. The use of health-foods and nutrient supplements was influenced by age, educational and economic level and self-estimated living status, but the trends in prevalence of both were not consistent. Health-foods were prefered by the groups of high educational career, affluent income and advanced living status, and low educational career, low income and low living status groups favored the nutrient supplements. The restrictive intake of animal fat and the use of health-food were positively correlated, which seemed that the subjects used health-foods as supplements in compensation for nutritional unbalance caused by the avoidance of animal protein foods.

• Korean journal of food and cookery science
• /
• v.12 no.3
• /
• pp.367-371
• /
• 1996

Camellia oil refined under laboratory conditions had a lower content of linoleic acid, higher oleic acid and lower iodine value than soybean oil. The oxidative stability of camellia oil from POV and AV was much higher than that of soybean oil during autoxidation. The acid values of both oils increased with frequency of frying whereas iodine value decreased. The significant decrease of iodine value of soybean oil compared to camellia oil is thought to be because more double bonds are present in soybean oil than in camellia oil. The result of sensory evaluation for taste, color, odor and total acceptance of potato chips fried with camellia, soy-bean and corn oil revealed that the potato chips prepared from camellia oil was the most favorable.

• The Korean Journal of Food And Nutrition
• /
• v.27 no.2
• /
• pp.156-163
• /
• 2014

In order to develop tea by using the leaves of stevia, which is a herbal plant, and to solve the disadvantages of stevia dried leaf tea, we have manufactured the steamed tea, stir-fried tea and fermented tea by changing the manufacturing processes. As a result of the sensory tests, the steamed tea, stir-fried tea and fermented tea received higher evaluations than the dried leaf tea. In terms of efficiency, it is desired that the total number of steaming and stir-frying is only once, but the fermentation is found to be the most desirable for 2 days. There are no trends for changes in the general ingredients, mineral and free amino acid contents of stevia leaf teas by different manufacturing processes. As a result for the measurement of antioxidant activities, the steamed tea and dried leaf tea did not show significant differences, but the stir-fried tea and the fermented tea show significantly low antioxidant activities as compared to the steamed tea. The contents of stevioside in both the stir-fried tea and the fermented tea were less than that in the dried leaf tea, but in the steamed tea, there was no significant difference in the content of stevioside. Base on the present observations, this study supports high potentials of steaming process in order to produce new stevia leaf tea.

• The Korean Journal of Food And Nutrition
• /
• v.26 no.2
• /
• pp.155-162
• /
• 2013

The purpose of this study was to compare the preferences for seafood in school lunch menus among elementary school students in Gyeonggi-do. A survey was carried out on 303 male/female elementary school students. As for the preferences for seafood in school lunch menus, 'like (47.2%)', 'fair (30.7%)', and 'dislike (22.1%)' were observed in that order (p<0.01). Concerning the appropriateness of seafood serving frequency, '1~2/week (44.9%)', '3~4/week (33.7%)', and 'everyday (10.2%)' were observed in that order. When the preference of favorite seafood was evaluated using a Likert scale (strongly like 5-points, strongly dislike 1-point), 'crustacea (4.34)', 'mollusk (4.21)', and 'processed food (4.11)' were observed in that order. In terms of cooking methods for seafood, 5th grade students showed higher frequency of 'grilling' and 'frying' seafood compared to others (p<0.05). As for the occurrence of seafood leftovers, 4th and 6th grade students showed higher frequency of 'sometimes' than 5th grade students (p<0.001). As for certain desires for seafood in school lunch menus, 'improvement of taste (39.3%)', 'various kinds of seafood (20.1%)', and 'variable cooking methods (18.5%)' were observed in that order. Therefore, in order to increase the intake of seafood, students should attempt to achieve proper intake though nutrition education.

• Korean journal of food and cookery science
• /
• v.23 no.3 s.99
• /
• pp.369-377
• /
• 2007

The aims of this study were to develop and standardize the manufacturing procedures and ingredient formulation of non-fried, extrusion-puffed Yukwa. The quality and storage stability of the non-fried Yukwa (NF) were characterized and compared against a traditional deep-fried Yukwa (F). The moisture contents of both the NF and F were almost comparable at 5.12${\sim}$6.22% after the final product preparation. The textural hardness values of the NF samples were one-half to two times as hard as those of F, although no clear distinctions were reported between the two products by the sensory evaluation results (p<0.05). During storage, the acid value of F was 1.68 KOH mg/g on day 7, and then it rapidly increased to 5.52 KOH mg/g on day 14. In contrast, the acidity values of NF were 1.21 and 2.62 KOH mg/g on day 7 and 14, respectively. The peroxide values of the samples increased from 23.5 to 62.0 meq/kg (F) and from 2.0 to 2.5 meq/kg (NF) during the two weeks of storage after preparation, suggesting excellent fat stability for the NF product. Regarding the sensory evaluation results of the products, no significant (p<0.05) differences were noted between F and NF with scores of approximately 3.1 out of 5.0 points for the overall quality characteristics of the final products. Accordingly, we conclude that extrusion puffing technology could be adopted as an alternative to conventional deep fat frying as a partial manufacturing process of Yukwa.

• Korean journal of food and cookery science
• /
• v.23 no.3 s.99
• /
• pp.378-387
• /
• 2007

In this study, we investigated the application of HACCP for a prepared side dish of sweet potato stems, within a free meal service system for the elderly in the Sungnam area. Total bacterial counts (TBC) and levels of coliforms and Esherichia coli (E.coli) were analyzed through an eight step cooking process. The TBCs of the raw samples ranged between 3.30 and 1.37${\times}10^4$ CFU/g per 100 cm$^2$ The trimmed, blanched, and drained sweet potato stems showed a mean TBC value of 1.37${\times}10^4$ CFU/g, and the level of coliforms was 1.48${\times}10^3$ CFU/g. Among the eight samples, however, after stir-frying and serving, the TBC decreased to a standard satisfactory level, and a coliforms and E. coli were not found. A five step process was used and samples were taken to check the microbial quality of the cook and cooking equipment. Here we tested for TBC, coliforms, Staphylococcus aureus (S. aureus), and Salmonella. Specifically, the TBC and number of coliforms were examined on the cook's hand's, cutting board, and knife, as they represented hazards for cross-contamination. The three inspection steps of preparation of the trimmed, rinsed, blanched, and drained sweet potato stems, cook's' hands, cutting board and knife were all considered CCPs, and a manual of cooking process management was established to improve the risk factors in this study. In conclusion, this study reinforces that microbiological analysis is as a valuable tool for checking what points and stages of the cooking process must be controlled.