• 한국축산식품학회지
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• 제32권4호
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• pp.448-457
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• 2012

The predictive ability for off-flavor development and quality change of ground beef was evaluated using a microbial time temperature indicator (TTI). Quality indices such as off-flavor detection (OFD) time, color, pH, volatile basic nitrogen (VBN), aerobic mesophilic bacteria (AMB) counts, and lactic acid bacteria (LAB) counts were measured during storage at 5, 10, 15, and $25^{\circ}C$, respectively. Arrhenius activation energies (Ea) were estimated for temperature dependence. The Ea values for TTI response (changes in titratable acidity (TA)), VBN, AMB counts, LAB counts, and freshness, which is defined based on OFD time for quality indices of ground beef, were 106.22 kJ/mol, 58.98 kJ/mol, 110.35 kJ/mol, 116.65 kJ/mol, and 92.73 kJ/mol, respectively. The Ea of microbial TTI was found to be closer to those of the AMB counts, LAB counts, and freshness. Therefore, AMB counts, LAB counts, and freshness could be predicted accurately by the microbial TTI response due to their Ea similarity. The microbial TTI exhibited consistent relationships between its TA change and corresponding quality indices, such as AMB counts, LAB counts, and freshness, regardless of storage temperature. Conclusively, the results established that the developed microbial TTI can be used in intelligent packaging technology for representing some selected quality indices of ground beef.

• Food Science and Biotechnology
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• 제16권2호
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• pp.325-328
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• 2007

Mesophilic aerobic bacterial counts were measured and compared for seasoned soybean sprouts produced in different seasons and sold in different market types. Very significant differences in microbial counts were found among seasoned soybean sprouts produced in different seasons (winter, spring, and summer) and among different market types (a traditional market, discount store, and department store). However, there was no significant difference among the stores within each market group. The interactions were significant at a 1% significance level. The variance of summer counts was much lower than spring and winter counts. Discount and department stores showed a higher variation in microbial counts than traditional markets. The microbial counts differed substantially from season to season in the same market group (summer > spring > winter) except between spring and summer in traditional markets. The microbial loads in the winter and spring seasons of seasoned soybean sprouts in traditional markets were clearly higher than in other market groups, while discount stores had the highest microbial count in summer.

• 한국식품위생안전성학회지
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• 제18권4호
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• pp.237-242
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• 2003

식품산업체에서 검사한 자료의 일반세균수는 대부분 불규칙 분포를 나타낸다. 최근 이러한 불규칙적인 경향에 대하여 미생물수의 lognormal 분포 특성을 이용하는 확률분포 모델을 적용함으로써 좀더 정확한 변화의 특성을 밝히고 있다. 확률분포 모델을 이요하면 일반세균수와 대장균군 등의 분석결과에 대해 과거의 단순한 경향분석을 벗어나, 유용한 분석이 가능한 것으로 나타나고 있다. 본 여구는 냉동만두류를 생성하는 2개 업체의 각각 1년 동안 실험된 일반세균 자료를 갖고, 확률분포 모델 활용의 타당성과 업체간의 위생수준 상호비교 그리고 예상되는 위해발생 예측에 적용 검토하였다. 그 결과 정량적인 미생물 자료에 대한 확률분포 모델의 적용은 식품산업체에서 일반세균수에 의한 위해발생 가능성을 예측하고 안전관리 수준을 결정하는데 유용한 것으로 판단된다.

• Asian-Australasian Journal of Animal Sciences
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• 제19권2호
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• pp.292-296
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• 2006

Meat marination has been applied to improve product's physical and sensory attributes for years, but usually it is not intended to improve microbial quality of the product. Tumbling, which helps the distribution of marinade solution during processing, should enhance the action of antimicrobial agents. The objective of this study is to evaluate the combined effects of nisin, tumbling and storage time on total microflora and psychrotrophs counts on poultry. A marinade that contained acetic acid (1%) and salt (3%) with pH adjusted to 4 was developed as a standardized marinade. Drumsticks were marinated with various nisin levels (0, 50, or 100 IU/ml) combined with tumbling (0, 10, or 20 min), and then stored at $4^{\circ}C$ for 18 h. The total microflora and psychrotrophs counts of the samples were evaluated after 0, 2, 4, and 7 days of storage. The results indicated that at a given storage time, the samples tumbled for either 10 or 20 min had significantly (p<0.05) lower microbial counts when compared with the samples without the tumbling treatment. The microbial counts of the tumbled samples increased as storage time increased. Microbial counts significantly (p<0.05) decreased when more nisin was increased up to the level of 100 IU/ml. In conclusion, adding of nisin at the level of 50 IU/ml with tumbling for 10 min decreased the total microflora and psychrotrophs counts of the marinated chicken broiler drumsticks.

• 한국식품조리과학회지
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• 제21권5호
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• pp.557-566
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• 2005

The purpose of this study was to estimate the microbial quality of some raw vegetables and to suggest a safer method of sanitization and pre-preparation in foodservice operations. The production of Dotori-muk muchim was monitored from ingredient preparation to final product and during holding at different temperatures. Three sanitization methods were performed during the preparation with crown daisy (tap water, chlorine water, electrolyzed water). The largest reduction of microbial counts was for electrolyzed water (after treatment, total plate counts were decreased to $2.76{\sim}3.76$ Log CFU/g, coliform counts were not detected). In the case before immersed in chlorine water, Performed first washing is larger the effective reduction of microbial counts than or not.

• 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).

• Advances in environmental research
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• 제2권1호
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• pp.61-80
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• 2013

Quantification of viable forms of microbial community (bacteria and fungi) using culture-dependent methods was done in order to characterize the indoor air quality (IAQ). Role of those factors, which may influence the concentration of viable counts of bacteria and fungi, like ventilation, occupancy, outdoor concentration and environmental parameters (temperature and relative humidity) were also determined. Volumetric-infiltration sampling technique was employed to collect air samples both inside and outside the schools. As regard of measurements of airborne viable culturable microflora of schools during one academic year, the level of TVMCs in school buildings was ranged between 803-5368 cfu/$m^3$. Viable counts of bacteria (VBCs) were constituted 63.7% of the mean total viable microbial counts where as viable counts of fungi (VFCs) formed 36.3% of the total. Mean a total viable microbial count (TVMCs) in three schools was 2491 cfu/$m^3$. Outdoor level of TVMCs was varied from 736-5855 cfu/$m^3$. Maximum and minimum VBCs were 3678-286 cfu/m3 respectively. Culturable fungal counts were ranged from 268-2089 cfu/$m^3$ in three schools. Significant positive correlation (p < 0.01) was indicated that indoor concentration of viable community reliant upon outdoor concentration. Temperature seemed to have a large effect (p < 0.05, p < 0.01) on the concentration of viable culturable microbial community rather than relative humidity. Consistent with the analysis and findings, the concentration of viable cultural counts of bacteria and fungi found indoors, were of several orders of magnitude, depending upon the potential of local, spatial and temporal factors, IO ratio appeared as a crucial indicator to identify the source of microbial contaminants.

• 한국식품저장유통학회:학술대회논문집
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• 한국식품저장유통학회 2003년도 제23차 추계총회 및 국제학술심포지움
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• pp.188.1-188
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• 2003

To examine the effect of vacuum packaging on the quality of chicken during storage, microbial (total bacterial counts, mold and yeast, E. coli, and Pseudomonas) changes and drip loss were determined. fresh chicken breasts were prepared and packaged using polyethylene film under vacuum and normal atmosphere, respectively. Samples were then stored at 4$^{\circ}C$ for two weeks. At various time intervals during storage, sample was taken homogenized, and diluted with 0.1% sterile peptone water, and followed by microbial counts. Microbial changes of total bacterial counts, mold and yeast, E. coli, and Pseudomonas during storage of chicken were significantly decreased by vacuum packaging. Drip loss was also significantly decreased. These results indicate that vacuum packaging of chicken should be recommended as a suitable storage method in terms of microbial safety as well as quality of chicken.

• 한국식품조리과학회지
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• 제20권6호
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• pp.667-676
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• 2004

The purpose of this study was to estimate the microbial quality of some raw vegetables, and suggest a safer method for their sanitization and pre-preparation in foodservice operations. Baechu-geotjeori was monitored from the ingredient to the final product, during different holding temperature. Three sanitization methods were performed during the pre-preparation (tap water, chlorine water and electrolyzed water). The largest reduction in the microbial counts was shown with the electrolyzed water pre-preparation (after treatment; the total plate counts decreased to 3.34-4.06 Log CFU/g, coliform counts decreased to 1.40-1.45 CFU/g). Prior to immersion in the chlorine water, washing was first peformed to see if the was a larger effective reduction in the microbial counts.

• 한국동물위생학회지
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• 제30권2호
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• pp.191-196
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• 2007

The slaughter process for cattle will inevitably transfer some bacteria onto the carcasses. The goal of food safety programs is to minimize and effectively remove this contamination. This study was attempted by the Verif $EYE^{TM}$ machine-vision technology that might be useful for reducing microbial indicator counts and could reduce the contamination chance of E coli O157:H7 and Salmonella spp on beef carcasses. For the evaluation of the effectiveness of the Verif $EYE^{TM}$ technology, 80 samples were examined by the inspection device over 15 days. On an examination of FDS-positive samples compared to negative controls from the same carcasses, aerobic plate counts were bigger than the negative control samples (5.26 vs 4.60 log). Enterobacteriaceae counts were greater on the positive samples than the corresponding negative control samples (2.07 vs 1.17log). There was a consistent correlation between samples detected by the Verif $EYE^{TM}$ system with detectable counts. For example, 100% of positive samples had detectable APC and 91.2% of positive samples had detectable TCC. Therefore, if areas detected as positive for contamination by the Verif $EYE^{TM}$ system were removed from the carcasses, significant sources of microbial contamination will be reduced for objective compliance with HACCP. This results suggest that the use of Verif $EYE^{TM}$ machine-vision technology might be useful for reducing microbial indicator counts (APC, TCC) and could help reduce the risk of presence of E coJi O157:H7 and Salmonella spp on Beef carcasses.