• Proceedings of the KSME Conference
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• 2000.11b
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• pp.309-313
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• 2000

An experimental study was conducted to analyze the characteristics of the showcase refrigeration system during frosting and defrosting process. Test showcase was constructed with a cooling capacity of 3RT including 3 evaporators. The dynamic characteristics of the system under frosting and defrosting conditions were investigated. Refrigerant temperature and pressure of the system, dry bulb and wet bulb temperature of air passing through the evaporator, air flow rate and compressor power were measured.

• Culinary science and hospitality research
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• v.7 no.3
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• pp.85-98
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• 2001

This study was performed to describe the overall sanitation of baking utensils and equipments, employees, and environment in 9 bakeries. Microbiological tests on employees, utensils and equipments, were done according to standard procedure and included total plate count, coliforms, fungi and Staphylococcus aureus.. Microbiological testing is a value in determining hazards for developing a HACCP plan but were not detected throat and employee's hands before use. Staphylococcus aureus was detected nasal cavity and employees's hands after use. Employee's apron after use was detected fungi and coliform and was risk factor of cross-contamination to bread or cookies et al. Generally hygienic conditions of pan, kitchen board, knife, brush, and wooden scoop were worse than those of other baking utensils such as tray, bread tweezers, dusting brush and dish cloth. And refrigerator, freezer and fermentation chamber were detected fungi and coliforms. Total plate count of heating table, working table, distribution table, washbowl and refrigerator was increased in 2nd period. Temperature of refrigerator was 10.43$^{\circ}C$ and strict temperature control of refrigerations needs. Therefore, baking utensils and equipments were reguraly need to sterilize and clean. Additionary, it need to practice the effective sanitation education and training program for the bakery managers and employees.

• Journal of the Korean Dietetic Association
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• v.19 no.3
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• pp.209-222
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• 2013

This study examined the hygiene practices of contract foodservice employees and investigated the influence of education and work environment on these hygienes practices. A questionnaire was distributed to 250 contract foodservice employees and a total of 232 responses were received and analyzed. The overall score for hygiene practices of contract foodservice employees was 3.89 based on a 5-point scale. Cross-contamination was prominent (highest score at 4.46) and the heating temperature was less prominent (lowest score at 3.49). The factors most affecting contract foodservice employees were their work period, the size of the contract foodservice management company, the number of meals served daily, the frequency of meal service per day and the frequency of hygiene education. Compared to small and medium-sized contract foodservice management companies, the major contract foodservice management companies showed higher scores for refrigerator/freezer control (P<0.001), vegetable/fruit disinfection (P<0.001), thawing (P<0.001), heating temperature (P<0.001), cleaning/disinfection (P<0.01), and personal hygiene (P<0.05). The frequency of hygiene education had a significant effect on the performance levels for refrigerator/freezer control (P<0.001), vegetable/fruit disinfection (P<0.001), thawing (P<0.001), heating temperature (P<0.001), cleaning/disinfection control (P<0.001), food supply control (P<0.05), and personal hygiene (P<0.05). From these results, to increase the sanitation quality of contract foodservice operations, hygiene practice levels need to increase and hygiene education systematically should be enforced for foodservice employees.

• Journal of the Korean Dietetic Association
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• v.30 no.1
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• pp.61-73
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• 2024

This report was prepared to introduce the developed Internet of Things (IoT)-based Smart Food Safety Management System (iMEAL) for children's foodservices registered in the Center for Children's Foodservice Management and report the results of hygiene monitoring through microbial analysis of two foods simulated and distributed based on this system. The program consisted of three menu screens: a foodservice management and meal inspection function, a refrigerator/freezer monitoring function, and a sanitary/safety inspection log function. Data such as cooking temperature, refrigerator and freezer temperature, salinity, and chlorine concentration were collected using IoT sensors or terminals, and hygiene safety inspection diary results (recorded by cooks) were transmitted to the Internet and stored. The APCs (3.78±0.07 log CFU/g) and E. coli (not detected) in stir-fried pork teriyaki sauce and the heating process met cooking standards. Similarly, the APCs (4.05±0.05 log CFU/g) and E. coli (not detected) in cucumber/chomuchim, which was not heated, also met cooking standards. APCs increased over time when cooked food was left for 1 hour, 1.5 hours, or 2 hours but remained acceptedable. Based on hygiene monitoring results of these two foods, using the i-MEAL system resulted in the safe production and distribution of children's food.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.1
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• pp.62-70
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• 2005

In this study, the air-side heat transfer coefficients of several types of evaporators in the household freezer/refrigerators are investigated. The types considered in this work are: discrete flat plate fin-and-tube type(in-lined tube array), continuous flat plate fin-and-tube type(staggered tube array), and spine fin-and-tube type(in-lined tube array). The heat transfer correlations obtained from this study for each heat exchangers could expect heat transfer coefficients less than $5\%$ of errors. The result indicates that the air-side heat transfer performance of spine fin-and-tube type evaporator shows the highest value under dry conditions, but discrete flat plate fin-and-tube type evaporator shows the highest value among these three evaporators under frosting conditions.

• Journal of the FoodService Safety
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• v.2 no.2
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• pp.59-66
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• 2021

The results of the inspection based on the sanitation checklist and the measurement of refrigerator/freezer temperature, illuminance, and ATP were conducted at 12 school foodservices in Daiyue-district, Taian-city, Shandong Province, China, at the same time, and the results were as follows. Five items of 'Use sterilized cutting boards', 'Use sterilized knives', 'Use worktable after sterilization', 'Use sink after sterilization', 'Sterilize the interior/exterior of the refrigerator regularly' in the checklist inspection were found not to be performed (0%). Two items of 'Disinfect hands after washing', 'Equipped with hand sterilizer' and 'Sterilize the kitchen areas regularly' were investigated as being performed only in one foodservice (8%). The average illuminance of the receiving stand were 373.08±106.35 Lux, 8% when the standard (540 Lux or higher) was complied with, the average refrigerator temperature were 7.06±0.82℃, 38.9% when the standard (-2 to 5℃) was observed 8% of cases complying with the standard (below -18℃) at -8.56±0.76℃ were investigated. As a result of ATP measurement, the surfaces of knife edge, cutting board, refrigerator door handle, worktable, and sink, which are not sterilized at all, were not suitable (accept ratio 0%), sterilized food plate (accept ratio 54.2%) and utensil for preserved food (accept ratio 75%) had a relatively high accept ratio. China's hygiene regulations should be revised in the direction of strengthening disinfection practices for facilities, equipment, and the environment, and hygiene measures such as education on disinfection and preparation of economical disinfection methods should be established.

• The Journal of the Acoustical Society of Korea
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• v.38 no.3
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• pp.344-351
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• 2019

In this work, the mechanism of contraction and expansion noise generation is investigated, and effective methods are proposed to reduce the occurrence frequency of noise during operation of the refrigerator. First, the frequency spectrum analysis was made by using the sound pressure signal measured in an anechoic chamber to investigate the characteristic of noise and the frequency of occurrence. Second, a thermal deformation analysis was conducted to predict the location of noise source. It is found from the analysis that the biggest thermal deformation occurs in the middle of the left inner case in the freezer room. Following the investigation made, a noise reduction method is proposed. The method is proposed to reduce the contraction and expansion noise by reducing the thermal deformation through increasing ABS (Acrylonitrile Butadiene Styrene) thickness in the center of refrigerator.

• Journal of Food Hygiene and Safety
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• v.23 no.4
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• pp.304-308
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• 2008

We investigated temperature management for refrigerated foods in large discount markets, department stores, and convenience stores. Eleven stores in the Seoul area were used to examine temperature maintenance for frozen and refrigerated foods, including soybean curds (tofu), fish surimi, mook, wet noodles, kimbab, and salads. The surficial and central temperatures of foods in a refrigerator and a freezer were examined. While the difference between the highest ($7.5^{\circ}C$) and the lowest ($6.4^{\circ}C$) temperature spaces in a refrigerator was $1.1^{\circ}C$, the corresponding difference between the highest ($8.9^{\circ}C$) and lowest ($7.5^{\circ}C$) food surface temperatures was $1.4^{\circ}C$. The average temperatures of both chilled food surfaces and refrigerator spaces were $7^{\circ}C$ (max. $22.9^{\circ}C$) and 8.2 degrees C (in. $-0.4^{\circ}C$), respectively. The temperatures of chilled food surfaces were $6.1{\times}10.6^{\circ}C$ for soybean curds, $6{\sim}12.3^{\circ}C$ for fish paste, $2.3{\times}18.2^{\circ}C$ for kimbab, $4.6{\times}12.2^{\circ}C$ for salads, $3.4{\times}12.6^{\circ}C$ for wet noodles, and $7.1{\times}19^{\circ}C$ for mook. Our results indicate that chilled foods require careful management for storage at temperatures below $10^{\circ}C$ with careful recording of the warmest area of the refrigerator.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.11
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• pp.974-980
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• 2005

The optimization of design factors on the frosting performance of a fin-tube heat exchanger is carried out using Taguchi method. The fin spacings of the heat exchanger are selected as design factors. Optimum values of the design factors under operating conditions of a household refrigerator/freezer are proposed. The average heat transfer rate and operating time of the optimum models, compared to those of a reference model, are increased at most by $6.5\%$ and $12.9\%$, respectively.

• Korean journal of food and cookery science
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• v.11 no.5
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• pp.494-502
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• 1995

The study was conducted to evaluate the characteristics of Nuhbiani qualities with the different cooking, reheating methods and storage conditions. Cooking and reheating methods were used with pan, microwave and their combinations. Precooked samples were stored for 0, 1, 4, 7, 15 days in the refrigerator and for 15, 30 days in the freezer. TBA value, shear value by rheometer and sensory attributes in rancidity, hardness, juiciness and overall acceptability were measured. There was no significant difference between cooking, reheating methods in TBA values. Lower values in TBA were noted in the Nuhbiani of frozen storage as compared with that of refrigerated storage. There is a tendency that TBA values were increased as the storage time extended during the refrigeration. Shear values were more increased by microwave cooking and microwave reheating than other methods showing harder texture. Results from sensory evaluation of rancidity, hardness, juiciness and overall acceptability show that there were no significant differences between storage methods, among storage periods and cooking, reheating methods.