• Korean Journal of Food Science and Technology
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• v.17 no.3
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• pp.186-191
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• 1985

The effect of gamma irradiation on the physicochemical properties of chicken meat and its sensory quality were investigated during 41 days of storage at 3 to $4^{\circ}C$ following irradiation of 5 to 10 kGy. Immediately after irradiation, the water holding capacity of chicken meat decreased slightly with the increase of irradiation dose, whereas during storage, the water holding capacity of irradiated groups was superior to that of the nonirradiated ones. With increasing the irradiation dose and storage time, the TBA values of irradiated groups were higher than those of nonirradiated ones. The volatile basic nitrogen content of nonirradiated group markedly increased over 20mg% by microbial spoilage from the 10th day of storage, however, the irradiated groups of over 8 kGy showed only the 16 to 18mg% until 41 days of storage. The irradiated groups had a slight irradiation-odour that dissipated during up to 3 days of storage, and also they showed a slight pink discoloration in the carcasses and this tendency was much more pronounced with increasing irradiation dose. The nonirradiated group gave off an off-odour due to the spoilage around 5 to 7 days of storage and showed a change in meat appearance, while the irradiated groups of over 5 kGy maintained a fresh state during the 25 to 30 days of storage.

• Korean journal of food and cookery science
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• v.28 no.5
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• pp.515-530
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• 2012

This research aims to audit foodservice sanitation management practices and to assess microbiological quality of foods and their food contact environments in kindergartens. Sanitation auditing was conducted in 10 kindergartens in Seoul, Gyeonggi, and Incheon areas to assess the levels of safety practices. Results revealed that the surveyed kindergartens scored 41.4 out of 100 points, on average. The average scores of each category were 6.4/11 (58.1%) for facilities sanitation, 4.2/12 (35.0%) for equipment sanitation, 2.4/10 (24.0%) for personal hygiene, 5.1/10 (51.0%) for food ingredients management, 6.0/17 (35.3%) for production process, 5.4/10 (54.0%) for environmental sanitation, 2.0/6 (33.3%) for kitchen utensils sanitation, and 2.2/6 (96.7%) for safety management. Microbiological quality of raw, prepared foods, personal sanitation (hands), environmental sanitation, and drinking water were assessed. Total plate counts (TPC) of the following menus exceeded the critical limit: seasoned leek (5 log CFU/g), cucumber (5.0 log CFU/g), panbroiled fish paste (TNTC at $10^4$), tangpyeongchae (5.3 log CFU/g), egg rolls (6.1 log CFU/g), panbroiled sausage (TNTC at $10^4$), and soft tofu pot stew (TNTC at $10^4$). Coliform which exceeded the standard limit were detected from seasoned leek (2 log CFU/g), cucumber (2.5 log CFU/g), panbroiled fish paste (2.0 log CFU/g), egg roll (3.8 log CFU/g), tangpyeongchae (4.0 log CFU/g), panbroiled sausage (2.3 log CFU/g), and soft tofu pot stew (3.7 log CFU/g). For seasoned foods (muchim), S. aureus ranged 2.2~2.9 log CFU/g. In food workers' hands, microbial profiles ranged 3.8~7.9 log CFU/hand for TPC, ND~4.5 log CFU/hand for coliforms, ND~4.7 log CFU/hand for S. aureus, and ND~5.3 log CFU/hand for Enterobacteriaceae. Microbiological profiles of food contact surface of knives, cutting boards, dish-clothes, and trays showed possibilities of cross-contamination. General bacteria were 2.1~4.5 logCFU/ml in 4 purified water samples and E. coli were found in the kitchen of one kindergarten. These results suggested that environmental sanitation management practices need more strict improvement: effective sanitation education methods and practices were strongly required, and more strict sanitation management for cooking utensils and equipment were required.

• Journal of the Korean Dietetic Association
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• v.12 no.2
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• pp.172-184
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• 2006

This study was aimed to provide safety management guidance by evaluating the microbial quality of cooked dried-seafoods in school foodservice operations. Nineteen seafood items were collected from six elementary schools, those were dried-anchovy, dried-seaweed and dried-fish, which were classified as cooking process. The temperatures at receiving and after cooking were measured and the analyses of cooking processes and microbial quality were performed. The temperatures of all foods after cooking were higher than the temperature limit of $74\^circC$. The number of total aerobic bacteria and S. aureus in dried-anchovy over the limit of $10^5$ and even the level of S. aureus was found to be unsatisfactory. The count of total aerobic bacteria was 2.1x$10^8$ CFU/g and the number of total aerobic bacteria after cooking was over the limit in one school. The level of E. coli (3.1x$10^3$ CFU/g) was over the limit at one school and the number of S. aureus (1.2×$10^4$ CFU/g) was considered as unacceptable. Dried- tangle and green laver were contaminated with total aerobic bacteria showing the over the limit. The numbers of total aerobic bacteria in dried- filefish, pollack and squid were 4.3x$10^6$, 3.4x$10^6$-3.9x$10^7$ and 4.6x$10^5$-4.1x$10^7$ CFU/g, respectively, which were in acceptable or unsatisfactory level. The E. coli in dried- filefish and pollack were over the limit. The total aerobic bacteria levels, 4.6x$10^5$-1.5x$10^6$ CFU/g in dried-pollack and 8.0x$10^5$-2.2x$10^7$ CFU/g in dried-squid, were over the limit after cooking except dried-filefish. The E. coli levels, 4.3x$10^3$ CFU/g in dried-filefish and 2.5x$10^2$ CFU/g in dried-pollack, were over the limit of $10^2$ CFU/g. The numbers of Enterobacteriaceae were either acceptable (3.3x$10^3$ CFU/g) or unsatisfactory (1.6x$10^4$ CFU/g) level in dried-pollack. S. aureus was unsatisfactory level (6.5x$10^4$ CFU/g) in dried-filefish while unacceptable in dried-pollack both before and after cooking. Unacceptable levels of S. aureus, 2.4x$10^4$ and 1.3x$10^5$ CFU/g were found from two schools, respectively. These results suggest that the contamination of raw materials and the seasonings added after cooking should be controlled to manage the microbial safety of cooked dried-seafoods.

• Food Science and Preservation
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• v.13 no.1
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• pp.55-60
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• 2006

Two kinds of composite seasoning products (beef broth powder, polk bone extract powder) were used for a detection trial of gamma irradiation treatment up to 10 kGy by analyzing photostimulated luminescence (PSL), electron spin resonance (ESR) and thermoluminescence(TL). PSL results showed that the photon counts of non-irradiated samples were lower than 700, while those of irradiated samples were higher than 5000, which makes it possible to screen irradiated composite seasoning products at 1 kGy or over from the non-irradiated control. ESR signals measured for both irradiated samples were not irradiation-specific, even though they were dose dependent in the signal intensity. Radiation-induced TL glow curves were found in irradiated beef broth powder and furthernmore, TL ratio $(TL_4/TL_2)$ obtained by a re-irradiation step could verify the detection result of TL1 glow curves, showing ratios lower than 0.05 in the non-irradiated sample and higher than 1.00 in irradiated ones.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.1
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• pp.24-32
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• 1984

In order to process instant foods which hold appropriate moisture contents and soft texture, four kinds of retort pouched seasoned-oyster products were prepared as control, seasoned products, solid smoked and liquid smoked product after seasoning and their processing conditions and quality stability during 100 days of storage were investigated. The optimum processing conditions of retort pouched seasoned-oyster product were as follows ; namely, raw oyster was seasoned at $105^{\circ}C$ for 10 min with seasoning solution prepared from sugar, sorbitol, salt, monosodium glutamate and 5'-ribonucleotide and then dipped for 30 seconds in Smoke-EZ solution(Alpha Foods Co., Ltd.) after predried for 30 min in hot-air drier. After. smoking, the seasoned and liquid smoked oyster was dried at $40-42^{\circ}C$ for 2.5 hours, vacuum packed in plastic film bag, and sterilized in a hot water circulating retort at $120^{\circ}C$ for 16 min. Comparing their quality before and after sterilization, TBA value of all the products after sterilization slightly decreased and among texture profiles hardness, toughness and chewiness slightly decreased, while elasticity and cohesiveness were rarely changed. Color value (a value) of the product treated with solid smoke or liquid smoke increased after sterilization. During storage pH, VBM and water activity of all products changed little and TBA values of the solid smoked product and liquid smoked one were lower than that of the others. Viable cell count was negative and texture changed little during storage. As for color difference during storage, green meat appeared on the surface of control and seasoned product after 15 days storage, while the masking of green meat could achieved by solid and liquid smoking treatment. And liquid smelling treatment was more effective than solid smoking. As a conclusion, retort pouched seasoned-oyster product treated with liquid smoke kept their good quality during 100 days storage and it seemed to be consumed as one of the instant foods which hold appropriate moisture contents and soft texture.

• Korean Journal of Food Science and Technology
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• v.50 no.3
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• pp.331-338
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• 2018

The purpose of this study was to determine the optimum sterilization conditions for the production of retorted steamed egg using response surface methodology. Sterilization processes for eighteen conditions using varying sterilization temperature ($X_1$), time ($X_2$), and method ($X_3$) as the independent variables were carried out through a $3^2{\times}2$ experimental factorial design. Quality evaluations after sterilization included measurements of $F_0$ value ($Y_1$), peak stress ($Y_2$), pH ($Y_3$), color value ($Y_{4-6}$), and organoleptic test [preference for appearance ($Y_7$), overall acceptability ($Y_8$), and preference for texture ($Y_9$) and egg taste ($Y_{10}$)]. Dependent variables ($Y_{1-10}$) of eighteen conditions were more affected by temperature and time than by the sterilization method. Eight factors were selected among the dependent variables as significant factors related to the quality of the steamed egg. Finally, by establishing an optimum range of each dependent variable and contour analysis, the optimum sterilization conditions for the production of steamed egg were determined to be $120^{\circ}C$ for 25 min using a 2-step sterilization process.

• Journal of Dairy Science and Biotechnology
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• v.16 no.2
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• pp.90-97
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• 1998

This study was carried out to investigate changes of microbiological and sensory properties in various heat-treated market milks (LTLT, HTST, and UHT milks) stored at 10$^{\circ}C$ during 15d. Titratable acidity (TA) increased with storage, while pH tended to decrease. During the initial 9d, no difference was found in TA, however, after 9d, it was slightly higher in HTST and UHT milks than that in LTLT milk. In LTLT and HTST milks, total viable cells and psychrotrophs were dramatically increased during storage, In addition coliform and pathogenic bacteria were found at 12 and 15d. In UHT milk, total viable cells were found only at 15d. In sensory evaluation, LTLT and HTST milks developed a negligible off-flavor until 9d. At 12d, it became stronger in HTST milk than that in LTLT milk. In UHT milk, off-flavor was detected at 9d and increased rapidly there-after. The degree of off-flavor was little higher in HTST and UHT milks, compared with that of LTLT milk after 9d storage. These observations indicated that LTLT and HTST milks may not be microbiologically acceptable after 5d, while off-flavor was not detectable until 9d, In comparison, UHT milk keeps a good quality in microorganism until 15d, however, it may not be accepted in sensory aspect after 9d storage.

• Journal of the East Asian Society of Dietary Life
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• v.21 no.5
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• pp.706-712
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• 2011

This study was carried out to investigate the quality characteristics and microbiology of the simple preprocessed food julienne white radish and pear during storage at $4^{\circ}C$ and fordevelopment of a standard recipe. Total aerobic bacteria level were $3.20{\pm}0.08$ log CFU/g in julienne white radish and pear, and $3.00{\pm}0.14$ log CFU/g in julienne white radish (control). Coliform counts were $3.20{\pm}0.08$ log CFU/g in julienne white radish and pear and $1.84{\pm}0.17$ log CFU/g in julienne white radish. Low levels of coliform and total aerobic bacteria were detected. pH values of julienne white radish and pear increased significantly after 3days, whereas that of control increased significantly after 1day. Lightness and redness decreased during storage, whereas yellowness increased significantly during storage. During storage, hardness of julienne white radish and pear decreased after 3days, whereas that of julienne white radish decreased after 5days. According to sensory evaluation, 70% julienne white radish and 30% julienne pear showed higher score in term of taste, harmony of ingredient, harmony of sauce and overall preference. Consequently, 70% julienne white radish and 30% julienne pear was determined to the best formula and a maximum storage period of 3 days was showned to be optimal.

• Journal of Food Hygiene and Safety
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• v.13 no.4
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• pp.319-331
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• 1998

The purposes of this study were to develop Hazard Analysis Critical Control Point plan applicable to cook/chilled Pork Bulkogi (broiled sliced pork with sauces) in school foodservice operations and to establish reasonable shelf-life limits by assessing food quality during chilled storage period of 5 days. During the product flow, time-temperature profile was recorded and microbiological analyses including mesophilic and psychrotrophic total plate counts, coliform, and fecal coliform and qualitative analyses of Salmonella and Listeria monocytogenes were done. Chemical analyses (pH, acid value, total volatile basic nitrogen), sensory evaluation, and quantitative analysis of thiamin were conducted for 5 days of chilled storage. The number of mesophiles in raw pork ($4.26{\pm}0.11\;Log\;CFU/g$), seasoning mixture ($5.97{\pm}O.04\;Log\;CFU/g$) and marinated pork ($5.56{\pm}0.21\;Log\;CFU/g$) were below the microbial standards for "requires further cooking" food items. Listeria monocytogenes was detected in seasoning mixture. After heating, the number of mesophiles ($5.17{\pm}0.04\;Log\;CFU/g$) were slightly reduced but it did not meet the microbial guidelines of $5\;Log\;CFU/g$ for "ready-to-eat" foods. No other microbes including pathogens were detected. By reheating the menu item after chilled storage, the number of mesophiles were reduced in every phase of 1st day ($4.62{\pm}0.22\;Log\;CFU/g$), 3rd day ($4.55{\pm}0.20\;Log\;CFU/g$) and 5th day ($4.25{\pm}0.16\;Log\;CFU/g$) of chilled storage, and the number of microbes was below the standard limits for "ready-to-eat" foods. At the fifth day of chilled storage, pH (p<0.05), acid value (p<0.01) and TVBN (p<0.05) showed significant increases. Sensory evaluation results did not show any significant change for 5 days of chilled storage. Thiamin content showed a decrease for 5 days of chilled storage. Consequently, the ideal shelflife recommended for Pork Bulkogi was within 3 days of chilled storage. CCPs for Pork Bulkogi were purchasing and receiving of raw meat and some seasoning ingredients, heating, chilling, chilled storage, reheating, and distribution.

• Journal of Bio-Environment Control
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• v.21 no.4
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• pp.411-418
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• 2012

This study was conducted to investigate the effect of calcinated calcium (CC) alone or combination with heat treatment on storage quality and microbial growth in fresh-cut broccoli. Fresh broccoli samples were cut into small pieces and washed in normal tap water (TW), $50{\mu}L{\cdot}L^{-1}$ chlorinated water (pH 6.5), $1.5g{\cdot}L^{-1}$ CC, heat treatment in TW at $45^{\circ}C$, and CC dissolved in TW at $45^{\circ}C$ for 2 minutes separately. Samples were then packaged in $50{\mu}m$ polyethylene bags and stored at $5^{\circ}C$. Results revealed that like $50{\mu}L{\cdot}L^{-1}$ chlorine, washing in CC at normal water temperature was effective in reducing microbial population in fresh-cut broccoli samples. Washing with CC combined with heat treatment increased an electrical conductivity of fresh-cut broccoli. Combined heat treatments with TW and CC reduced aerobic plate count on fresh-cut broccoli, only in initial period of storage. But, later on heat treatment induced injury of fresh-cut broccoli resulting more microbial population compared to non heat treatment. However, samples treated with CC alone had good quality with low off-odor at the end of storage. Results suggest that CC, an environment-friendly sanitizer could be an alternative to chlorinated water for washing of fresh-cut broccoli without affecting sensorial quality.