• 한국식품저장유통학회지
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• 제11권4호
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• pp.522-529
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• 2004

In the grilled fish paste stored at $5^{\circ}C$, the total aerobic bacterial counts were effectively reduced by 2.5 kGy or more. In the samples stored at $30^{\circ}C$, the total aerobic bacterial counts of the samples irradiated at 7.5 kGy were below to the limit of detection (2 log CFU/g). The TBA values of the irradiated samples were considerably higher than those of the controls but not proportional to the irradiation dose. It is apparent that an irradiation treatment causes very little textural degradation and the sensorial quality of the sample was maintained by an irradiation at 7.5 kGy or more.

• 한국환경과학회지
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• 제10권3호
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• pp.239-245
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• 2001

This research was performed to investigate the dynamics of microbial community by RBC (Rotating Biological Contactor) using Rhodococcus sp. EL-GT and activated sludge. Cell counts revealed by DAPI were compared with culturable bacterial counts from nutrient agar. Colony counts on nutrient agar gave values 20~25% and 1~15% of cell counts (DAPI). The cell counts for the dynamics of bacterial community were determined by combination of in situ hybridization with fluorescently-labelled oligonyucleotide probes and epifluorescence microscopy. Around 90~80% of total cells visualized DAPI were also detected by the bacteria probe EUB 338. For both reactors proteobacteria belonging to the gamma subclass were dominant in the first stage (1 and 2 stage) and proteobacteria belonging to the gamma subclass were dominant in the last stage (3 and 4 stage).

• Preventive Nutrition and Food Science
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• 제9권3호
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• pp.232-235
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• 2004

Since ready-to-use (RTU) products are not fully cooked, the shelf-life of the product is comparably short and the products are easily spoiled when contaminated with food-borne pathogens. Low-dose gamma irradiation of 0.5, 1, or 2 kGy effectively reduced the total aerobic bacterial counts in 2 Korean manufactured RTU products by 1.63 to 2.95 log CFU/g during cold storage. Irradiation at 2 kGy reduced the psychrotrophic bacterial counts in most of the samples to below the limit of detection (< log CFU/g). Irradiation at 0.5 kGy completely eliminated Escherichia coli from the commercial RTU samples.

• Asian-Australasian Journal of Animal Sciences
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• 제27권11호
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• pp.1623-1629
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• 2014

Dry-cured pork neck samples were stored at $10^{\circ}C$ for 90 days under vacuum packaging (VP) or modified atmosphere packaging (MAP; 25% $CO_2$+75% $N_2$) conditions. The pH, moisture, water activity, total aerobic bacteria, and Enterobacteriaceae counts of dry-cured pork neck products with MAP were significantly lower than those with VP (p<0.05) after 90 days of storage. However, CIE $b^*$ and 2-thiobarbituric acid reacted substance (TBARS) values of the pork product with MAP were significantly higher (p<0.05) than those with VP. Total aerobic bacterial counts and Enterobacteriaceae counts of samples with MAP were lower than those with VP after 30 days of storage. Sensory results indicated that aroma, flavor and tenderness scores of the samples with both VP and MAP decreased during storage and the scores after >60 days of storage were lower than those at Day 1. In conclusion, despite presenting higher lipid oxidation, the samples stored in packages containing 25% $CO_2$ for 90 days at $10^{\circ}C$ have lower bacterial counts than vacuum-packed samples. Therefore, further studies should be performed on the packaging of dry-cured meat at adjusted concentrations of $CO_2$.

• Journal of Applied Biological Chemistry
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• 제51권3호
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• pp.128-135
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• 2008

A total of 142 samples comprising vegetables, soil, and water collected from different agricultural farms (five provinces) were analyzed for total aerobic bacteria (aerobic plate count [APC]), Bacillus cereus, Escherichia coli, Listeria monocytogenes, Salmonella spp., and Staphylococcus aureus. The average of total APC in all the samples ranged from $4.72{\times}10^5$ to $8.62{\times}10^8\;CFU/g$ (mL). The prevalence of B. cereus, E. coli, L. monocytogenes, S. spp., and S. aureus for all samples was 17.60%, 2.11 %, 1.4%, 0%, and 2.11 % respectively, and their counts averaged to $4.87{\times}10^4\;CFU/g$ (mL), $4.34{\times}10^3\;CFU/g$ (mL), $2.15{\times}10^2\;CFU/g$, 0 CFU/g, and $3.12{\times}10^3\;CFU/g$ respectively. Among the 3 different types of samples, 6 vegetables (10.34%), 24 soil (38.70%), and 3 water (13.64%) samples were found to be positive for bacterial pathogens. The result showed that the occurrence of bacterial pathogen in the samples analyzed was low. Further time to time monitoring and need to wash of raw agricultural products is recommended.

• 한국축산식품학회지
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• 제30권1호
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• pp.141-147
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• 2010

극한 환경에서 취식이 가능하도록 안전성 및 기호성이 확보된 덮밥 소스류 개발을 위한 기초연구로 많이 소비되고 있는 화닭 덮밥소스의 위생화를 위해 감마선 조사 기술을 적용하고 레토르트 살균과의 비교연구를 진행하였다. 화닭 덮밥 소스의 미생물 오염도 평가 결과 레토르트 비처리군은 총세균수가 4.5 log CFU/g 검출되었고 레토르트 처리군은 2.1 log CFU/g의 총 세균이 검출되었다. 반면 3 kGy의 감마선 처리군 에서는 검출한계 이하의 세균이 검출되었다. 검출된 미생물을 동정한 결과 Bacillus spp.로 확인되었으며, B. cereus 및 B. subtilis에 대한 방사선 감수성 측정 결과 각각 0.39 및 0.28 kGy로 확인되었다. SOS chromotest를 이용한 유전독성학적 안전성 평가 결과 감마선 조사에 의한 돌연변이원성은 관찰되지 않았다. 이상의 결과를 종합하여 볼 때, 화닭 덮밥 소스의 효과적인 위생화를 위하여 3 kGy의 감마선 조사처리가 레토르트 처리보다 효과적으로 미생물을 사멸하는 것으로 확인되었다.

• 한국패류학회지
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• 제24권1호
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• pp.25-32
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• 2008

In order to estimate the necessity of refrigerated storage of fresh seafood for short-term storage, and evaluate the effect of refrigerated storage on pen shell Atrina pectinata and clam Ruditapes philippinarum collected from Jang-su of Deukryang Bay and I-mok of Sunchen Bay in South Korea, the counts of coliform, Escherichia coli and total aerobic bacteria in A. pectinata and R. philippinarum under non-refrigerated $(28{\pm}1^{\circ}C)$ and refrigerated storage conditions $(4{\pm}1^{\circ}C)$ were determined. The results indicated that the storage at temperature of $4^{\circ}C$ possessed significant effects on inhibiting bacterial growth in live seafood. And refrigerated storage had different effect on A. pectinata and R. philippinarum. Different species and culture environments significantly influenced the initial and ultima bacteria counts. This study confirmed that refrigerated storage for short-term storage of live seafood was necessary, and indicated that the effect of refrigerated storage was influenced by comprehensive effectors.

• 한국축산식품학회지
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• 제34권1호
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• pp.73-79
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• 2014

This study was performed to evaluate the quality characteristics of three deboned categories of chicken thigh meat: one which was slaughtered and deboned in the same plant (fresh); one which was slaughtered, deboned, frozen, and thawed in the same plant (frozen-thawed); and the last which was slaughtered in a plant, deboned in a different plant, but then transferred to the original plant (fresh-outside). Surface color, drip loss, 2-thiobarbituric acid reactive substances (TBARS) value, sensory evaluation, and total aerobic bacterial counts of the chicken samples were determined. Moreover, the torrymeter was used to measure the differences in freshness of the chicken meat. The surface color and the TBARS values did not show significant differences among the three categories. However, the total aerobic bacterial counts of fresh-outside and frozen-thawed chicken meat were significantly higher than the fresh chicken meat on the first storage day, and the drip loss of frozen-thawed chicken meat was significantly higher than the fresh-outside and fresh chicken meat. In addition, the sensory evaluation of frozen-thawed chicken meat was significantly lower than the fresh-outside and fresh chicken meat. Torrymeter values were higher in fresh chicken meat than fresh-outside and frozen-thawed chicken meat during the storage period. These results indicate that the quality of frozen-thawed chicken meat is comparatively lower than the fresh chicken meat, and the torrymeter values can accurately differentiate the fresh-outside and frozen-thawed chicken meat from the fresh ones.

• 한국축산식품학회지
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• 제37권4호
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• pp.494-501
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• 2017

This study investigated the effect of injecting pineapple concentrate and honey into low marbled beef in order to enhance its sensory qualities, particularly tenderness and flavor, without compromising its fresh appearance. Beef loin was injected with a solution of 6.0% pineapple concentrate, 2.5% honey, 0.5% monosodium L-glutamate, 0.5% phosphate, and 0.3% salt (w/w) to 120% (w/w) of initial meat weight and stored for 14 d. Non-injected beef loin served as a control. Total aerobic bacterial counts, surface meat color, shear force, reducing sugar content, and sensory evaluation of the beef were analyzed at 0.5, 7, and 14 d of storage. Injection did not affect the total aerobic bacterial counts or color of the beef. However, injection increased the stability of meat color, compared with that of the control, during storage. The shear force value was significantly lower in the injected beef than that in the control. The injected beef had a significantly higher reducing sugar content compared with that of the control. In sensory evaluation, tenderness, juiciness, flavor, and overall acceptance of the injected beef were significantly higher than those of the control at 0.5 d. In conclusion, injection of pineapple concentrate and honey can improve the sensory qualities of low marbled beef, during short storage periods, without changing the fresh appearance of the beef.

• 한국축산식품학회지
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• 제34권4호
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• pp.525-532
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• 2014

This study was designed to elucidate the effect of ozone exposure on the bacteria counts and oxidative properties of ground Hanwoo beef contaminated with Escherichia coli O157:H7 at refrigeration temperature. Ground beef was inoculated with 7 Log CFU/g of E. coli O157:H7 isolated from domestic pigs and was then subjected to ozone exposure ($10{\times}10^{-6}kg\;O_3h^{-1}$) at $4^{\circ}C$ for 3 d. E. coli O157:H7, total aerobic and anaerobic bacterial growth and oxidative properties including instrumental color changes, TBARS, catalase (CAT) and glutathione peroxidase (GPx) activity were evaluated. Ozone exposure significantly prohibited (p<0.05) the growths of E. coli O157:H7, total aerobic and anaerobic bacteria in ground beef samples during storage. Ozone exposure reduced (p<0.05) the CIE $a^*$ value of samples over storage time. The CIE $L^*$ and CIE $b^*$ values of the samples fluctuated over storage time, and ozone had no clear effect. Ozone exposure increased the TBARS values during 1 to 3 d of storage (p<0.05). The CAT and GPx enzyme activities were not affected by ozone exposure until 2 and 3 d of storage, respectively. This study provides information about the use of ozone exposure as an antimicrobial agent for meat under refrigerated storage. The results of this study provide a foundation for the further application of ozone exposure by integrating an ozone generator inside a refrigerator. Further studies regarding the ozone concentrations and exposure times are needed.