• Journal of the Korean Society of Food Culture
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• v.25 no.5
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• pp.598-606
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• 2010

Kimchi is the most well-known Korean traditional food, but it is also the main leftover of school lunch and dinner menus. This study aimed to familiarize teenagers with kimchi through school meals and to increase their daily kimchi intake, ultimately by appealing to the young generation's taste. A questionnaire survey was conducted in the Ansan area to examine student's acceptability of kimchi and their attitudes toward kimchi. Approximately 65% of males and 67% of female students liked the moderately fermented and pungent taste of kimchi. Kimchi served in school meals was regarded as nutritional but cheap. Approximately 72% of male and 82% of female students responded that they liked menu items using kimchi. Approximately 48% of students responded that menu items using kimchi in schools are not diverse. Students preferred meat as an ingredient in kimchi. The preferred cooking methods were stir-frying and frying, whereas boiling was the least favorite. Based on the survey results, ten kimchi menu items had been developed. The suitability of the menu was evaluated by students and cooks. Six kimchi items, including Kimchi mixed with rice, chicken, soybean sprouts, Kimchi cheese rice, stewed beef ribs with kimchi, rice topped with kimchi curry, kimchi cheese meat roast, and kimchi udong were considered appropriate for school meals, whereas kimchi kangchong, kimchi topokki, kimchi stew with surimi, and frozen Pollack kimchi soup were not suitable as menu items. Kimchi topokki was not accepted by students, while kimchi kangchong was not accepted by cooks. Cooks judged the suitability of a menu item by the cooking process and cooking times, whereas students judged an item by its sensory preference. Approximately 63% of students responded that kimchi intake has increased by participating in the development of kimchi dishes.

• Journal of the East Asian Society of Dietary Life
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• v.25 no.5
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• pp.893-901
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• 2015

This study investigated the effects of thawing conditions on physiological activities and quality of peeled garlic. Peeled frozen garlic was analyzed after thawing at low temperature ($4^{\circ}C$), room temperature ($20^{\circ}C$), tap water ($20^{\circ}C$), radio frequency of 27.12 MHz, and 2.45 GHz in a microwave. As a result, the time required to thaw garlic to $0^{\circ}C$ by various thawing methods was shortest at2.45 GHz in a microwave, followed by $20^{\circ}C$ tap water, radio frequency of 27.12 MHz, $20^{\circ}C$, and $4^{\circ}C$. Microwave thawing was faster than other methods, but it resulted in significant non-uniformity of heating. The hardness of peeled garlic significantly decreased upon freeze-thawing, whereas it showed improved hardness upon radio-frequency thawing. Total color difference in garlic increased upon freeze-thawing, and it was not improved by various thawing methods. Antioxidant activities were determined for DPPH radical scavenging ability, SOD-like activity, and reducing power. Total phenolic compounds and flavonoids in garlic extract were measured as $3.222{\pm}0.214{\mu}g$ GAE/g and $0.149{\pm}0.03{\mu}g$ QE/g, respectively. The content of total phenolic compounds was significantly reduced by 2.45 GHz microwave thawing ($1.90{\pm}0.02{\mu}g$ GAE/g); however, flavonoid contents were slightly reduced under freezing and thawing conditions. The DPPH radical scavenging ability of garlic extracts was not affected by thawing methods; however, SOD-like activity and reducing power were slightly reduced by freeze-thawing. These results indicate that physiological activities were not improved by radio-frequency thawing; however, thawing time and maintain hardness were reduced compared with conventional thawing methods.

• Journal of Bio-Environment Control
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• v.18 no.1
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• pp.60-66
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• 2009

This study was conducted to investigate into the effective drying method for three greens such as bang-a (Isodon japonicus), aster (Aster yomena) and lettuce greens (Ixeris dentata) Nakai. We have dried three greens using the different drying methods, have made methanol extracts and have also determined the physiological activities in $1,000mg{\cdot}L^{-1}$ extracts. Total phenolic compound contents were most increased by 65.1 and $60.2mg{\cdot}L^{-1}$ in the extracts of bang-a and aster which were frozen dried, however, that in lettuce greens were oven dried by $51.2mg{\cdot}L^{-1}$. Total flavonoid contents were extremely much more in bang-a extracts dried in the oven by $70.6mg{\cdot}L^{-1}$, however, aster and lettuce greens extracts frozen dried by 53.9 and $35.8mg{\cdot}L^{-1}$. DPPH radical scavenging activity in bang-a extracts were greatly increased by 78.8% when bang-a were frozen and dried, however, that in aster were not significant by $89.8{\sim}90.9%$. DPPH radical scavenging activities in lettuce greens extracts were became highest in the order f oven drying (91.9%), natural drying (91.0%) and freeze drying methods (90.9%). Nitrite radical scavenging activities in bang-a and aster extracts were most increased in the natural drying treatment by 73.3 and 78.2%, however, that in lettuce greens extracts were highest in freeze drying treatment by 75.1%.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.10
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• pp.8-14
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• 2017

Improvements in the standard of living and lifestyle have led to increased sales of frozen milk products, such as soft ice cream or slush. These frozen milk products are commonly made in a small refrigeration machine. In a soft ice cream machine, the freezer is composed of a concentric cylinder, where the refrigerant flows in the annul us and the ice cream is made in the cylinder by a rotating scraper. In this study, an optimization and performance evaluation were conducted on a soft ice cream machine having a freezer volume of 2.8 liters. The optimization was focused on the scraper rotation speed and the refrigerant path of the freezer. The measurements included the temperature, pressure and consumed power. At the optimized speed of 124 rpm, ice cream was produced in 6 minutes and 2 seconds, and the COP was 0.90. Through a flow visualization study using air-water, the refrigerant path was improved. The improved design reduced the ice cream making time significantly. The present results may be used for the optimization of other refrigeration cycles, including those of frozen food products.

• Food Science and Preservation
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• v.16 no.6
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• pp.824-829
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• 2009

Changes in pH, viable microbial count, chemical freshness, texture, and sensory qualities of Sing Sing Hoe (SSH, fresh-sliced raw fish) were measured over 15 days at $4^{\circ}C$, $-20^{\circ}C$, and $-80^{\circ}C$. The initial pH of SSH was 6.25 at all three storage temperatures, and pH increased slightly after 12 days to pH 6.48 and pH 6.55 at $-20^{\circ}C$ and $-80^{\circ}C$, respectively. The range in viable cell count was 104-106 CFU/g, regardless of storage temperature. The initial content of volatile basic nitrogen (VBN) was 5.8 mg/100 g and became 8.2 mg/100 g or less, and 7.9 mg/100 g or less after 15 days at $-20^{\circ}C$ and $-80^{\circ}C$, respectively. However, pH and VBN values increased significantly after 3 days of storage at $4^{\circ}C$. At this temperature, the K-value was 22.3% after 6 days and 40% or more after 15 days. At $-20^{\circ}C$, the K-value was 9.6% or less after 6 days and 21% or less after 15 days of storage. At $-80^{\circ}C$, the K-value was 8.5% or less after 9 days and 20% or less after 15 days of storage. Compared with the K-value of live fish muscle (10%), freshness similar to that of live fish was maintained for 6 days under both $-20^{\circ}C$ and $-80^{\circ}C$ storage conditions. There was no significant change in texture during storage of SSH at $-20^{\circ}C$ or $-80^{\circ}C$, but SSH stored at $4^{\circ}C$ showed a decrease in texture quality during storage. Sensory scores were high for material stored for up to 3 days at $4^{\circ}C$ and 6 days at $-20^{\circ}C$ or $-80^{\circ}C$. The overall freshness of SSH was maintained for up to 6 days, in comparison with fresh-sliced raw fish, under both frozen storage conditions.

• Food Science and Preservation
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• v.19 no.4
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• pp.611-618
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• 2012

This study was conducted to investigate the perception of the management of food service in schools. The subjects consisted of 271 school dietitians in the Daegu and Gyeongbuk areas. The questionnaire included the food temperature management and the frequency of the food quality confirmation. The sanitation performance of the delivery workers was evaluated with a 5-point Likert scale. The food items for which the proper temperatures while they were being received were difficult to maintain were as follows: ready-to-use vegetables, 49.8%; frozen foods, 30.3%; and fish paste, 27.7%. The frequencies of the food quality confirmation whenever the foods were received were as follows: for beef, 87.5%; pork, 84.5%; chicken, 84.1%; eggs, 73.4%; seafood, 59.4%; and processed foods, 52.8%. The total mean score of the dietitian-perceived sanitation management performance of the delivery workers was 3.86/5.00. The school dietitians said the percentage of the mixed delivery of food items in vans was 80.4%. The percentage of the dietitians who thought this mixed delivery influenced food sanitation and quality was 92.3%. Therefore, safe foods should be supplied to schools with a thorough inspection process and hygiene education, and professional research is required on the appropriate inspection process.

• Journal of Food Hygiene and Safety
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• v.1 no.1
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• pp.77-95
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• 1986

In 1962 the governing bodies of FAO and WHO approved the establishment of a joint FAO/WHO Food Standards Programme, the creation of a jointly sponsored body to be known as the Codex Alimentarius commission to implement the Programme. It can reasonably be claimed that the Commission has assumad the leading role in establishing internation food standards throughout the world. The Codex Committee of Food Hygiene has received much advice and assistance from other international organization which have been working in this field for a number of years. In particular, it has received valuable background documentation from the International Commission on Microbiological Specifications for Foods(ICMSF) which was set up by the International Association of Microbiological Societies(IAMS), and also from the International Organization for Standardization (ISO). Nevertheless, in spite of the information supplied by governments and research bodies in this field, microbiological standards have proved to be a highly controversial subject from the point of view of Codex standards. When it is decided to establish a microbiological standard for a food or class of foods, the following technical and administrative aspects must be considered: 1) The standard should be based on factual studies and serve one or more of the following objectives: (1) to determine the conditions of hygiene under which the food should be manufactured; (2) to minimize the hazards to public health; (3) to measure the keeping quality and storage potential of the food 2) The standard should be attainable under practicable operating and commercial conditions and should not entail the use of excessive heat treatment or the additions of extra preservatives. 3) The standard should be determined after investigation of the processing operation. 4) The standard should be as simple and inexpensive to administer as possible, the number of tests being kept to a minimum. 5) Details of methods to be used for sampling, examining and reporting should accompany all published microbiological standards. 6) In establishing tolerance levels for the permissible number of defective samples, allowance should be made for sampling and other variations due to differences in the laboratory methods. The following additional points should be kept in mind: 1) It is not satisfactory to establish one set of microbiological standards for a miscellaneous group of foods, such as“frozen foods”or“precooked foods”. 2) Microbiological standards should be applied first to the more hazardous types of food on the basis of experience of expected microbiological levels, taking into account variations in composition, processing procedures, and storage. 3) When a standard is established, there should be a definite relationship between the standard and the hazard against which it is meant to protect the public. 4) The sensitivity, reliability, and reproducibility of the sampling and analytical methods should be compared in different laboratories and the methods to be used should be specified in detail as part of the standard. 5) Tolerances should be included in the standard to account for inaccuracies of sampling and analysis. 6) Standards should be applied on a voluntary basis before compliance is made mandatory.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.1
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• pp.126-136
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• 2016

This study was performed to investigate menu preferences of adult customers for Korean food made from Korean traditional sauces. A total of 962 valid responses were used for data analysis. Statistical analyses were conducted using the SPSS package program (ver 20.0). The results of this study are summarized as follows: overall preferences were highest for braised spareribs, followed by braised short ribs, grilled beef ribs, and bulgogi. On the other hand, overall preferences were lowest in eggplant namul, followed by squid and radish soup, and grazed lotus roots and burdock. Female's overall preferences were significantly higher than male's for nine menu items, including japchae and seasoned acorn starch curd with vegetables, whereas male's overall preferences were significantly higher than female's for 19 menu items, including grilled deodeok and frozen pollack stew. Moreover, the menu item that was most significantly preferred was soybean sprouts soup in subjects aged under 20 years and Korean meatballs in subjects in their twenties. Subjects in their forties showed significantly higher preferences for 15 menu items, including braised hairtail, grilled deodeok, and seasoned and grilled yellow corvina compared to other age groups. Furthermore, menu preferences of production service workers were significantly higher than other groups for frozen pollack stew, loach stew, grilled dried pollack, steamed dry pollack, dried pollack soup, eggplant namul, and seasoned and grilled yellow corvina, whereas menu preferences of official professional workers and students were significantly higher than those of production service workers for braised short ribs, grilled beef ribs, seasoned and simmered chicken, mixed noodles, Korean meatballs, stir-fried rice pasta with vegetables, spicy soft bean curd stew, japchae, mung bean jelly mixed with vegetables and beef, bibimbap, and stir-fried squid. The results show that menu preferences of adults customers differed depending on gender, age, and occupation. In conclusion, the results of this study should provide foodservice managers with information about menu planning for target customers of commercial or non-commercial foodservice cafeterias and recipe development of low-sodium Korean foods.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.3
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• pp.325-337
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• 2003

This study was designed to determine the distribution of trans fatty acids (tFAs) isomers of Processed foods commonly consumed in Korea. The tFAs positional isomers were analyzed using GC/MS spectrometer with HP-23 cis/trans FAME, capillary column (50m $\times$ 0.20 mm, id., 0.2 ${\mu}{\textrm}{m}$ film thickness) for 41 food samples. TFAs isomers were identified by comparing retention time with standards and GC/MS spectrum. In margarines, the content of tFAs ranged from 4.0% to 25.16% and the most abundant positional isomer of tFAs was C18:1 $\Delta$9t. In oils and fats, lards contained higher levels of tFAs (5.70~16.54%) than shortenings (6.77~10.55%). Shortenings contained higher levels of C18:1 $\Delta$9t (3.1~5.1%) than lard (1.6~4.3%), but corn oils had no tFAs. In seasonings, mayonnaise had no C16:1 $\Delta$9t, whereas C18:3t was detected. The content of tFAs in confectioneries was wide (16.20~52.16%). Among them, instant popcorns contained the highest amount of tFAs. Milk and dairy products showed even distribution of tFAS such as C18:1t, C18:2t, and C18:3t. Predominant tFAS isomer of condensed milk and ice cream was C16:1 $\Delta$9t. Frozen french fries and fried chicken contained higher levels of C18:1$\Delta$9t (9.4%), whereas grilled pork (jowl) had no C18:1 $\Delta$9t. The amount of tFAs per serving size was the highest in popcorn, followed by frozen pizza, frozen french fries, fried chicken, and bakeries.

• Journal of Food Hygiene and Safety
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• v.37 no.6
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• pp.400-410
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• 2022

This study was performed to analyze the microbial contamination levels of three non-heated rice cake manufacturers in terms of seasonal manufacturing process and to investigate the effects of summertime soaking on contamination levels and temperature-controlled soaking in water on reduction in microbial levels. The total aerobic bacteria (TAB) ranged from 2.69 log CFU/g to 5.08 log CFU/g in the produce, but the microbial contamination increased sharply during soaking. The levels of TAB and coliforms during summer soaking were 7.01 and 3.96 log CFU/g, respectively, and this was significantly higher than those in other seasons. The contamination level was high in the subsequent freezing, with the TAB level (6.24 log CFU/g) exceeding the legal standard. The temperature of soaking water in summer increased from 19.1℃ to 26.8℃ after 12 h of soaking. The microbial contamination was significantly high commensurate with increased soaking time, and the TAB level in the frozen process exceeded the legal standard from 9 h of soaking. The use of ice packs to prevent the increase in temperature of the soaking water in summer resulted in maintenance of temperature at 20.1℃ for up to 12 h. The average TAB value in the freezing process was 4.42 log CFU/g after 12 h of soaking, and this is 1.77 log CFU/g lower than that before. Based on these results, it was determined that controlling the soaking time and water temperature are essential for the production of a safe unheated frozen rice cake. The safety of the HACCP system could be established by applying these preventive management standards.