• Title/Summary/Keyword: microbial counts

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Application of a Prototype of Microbial Time Temperature Indicator (TTI) to the Prediction of Ground Beef Qualities during Storage

  • Kim, Yeon-Ah;Jung, Seung-Won;Park, Hye-Ri;Chung, Ku-Young;Lee, Seung-Ju
    • Food Science of Animal Resources
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    • v.32 no.4
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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.

Seasonal and Market Group Variation in the Microbiological Quality of Seasoned Soybean Sprouts

  • Park, Jin-Pyo;Kim, Hyoun-Wook;Lee, Dong-Sun;Paik, Hyun-Dong
    • Food Science and Biotechnology
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    • v.16 no.2
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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.

Application of the Fluctuating Microbial Counts Using Probability Approaches in Food Industries (식품산업체에서 확률분포 모델을 이용한 불규칙적인 미생물 수 분포 활용)

  • Park, Gyung-Jin;Kim, Sung-Jo;Sim, Woo-Chang;Chun, Seok-Jo;Choi, Weon-Sang;Hong, Chong-Hae
    • Journal of Food Hygiene and Safety
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    • v.18 no.4
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    • pp.237-242
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    • 2003
  • Sequences of industrial microbial counts of foods shows irregular fluctuating patterns as adeinition of fluctuating microbial counts(FMC). Recently, it beame clear that the FMC was considered as having a lognormal distribution as a first order approximation. Application of lognormal distribution to the industrial microbial counts could produce useful information in practice. This study is intended to verift the application method of lognormal idstribution in FMC. The one year's records for microbial counts of frozen dumplings from two companies were obtained, and the statistical analysis was carried out to estimate the frequencies of future events where counts exceeding selected levels and to compare the sanitation level of the two companies. The results showed that this spplication method enable translation of irregular recourds of microbial counts into an useful information such as te actual probalities of outburst of a given level and the quantitative predictions of potential hazards in the processing.

Applicability of Nisin and Tumbling to Improve the Microbiological Quality of Marinated Chicken Drumsticks

  • Tan, F.J.;Ockerman, H.W.
    • Asian-Australasian Journal of Animal Sciences
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    • v.19 no.2
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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.

Quality Dependence on Sanitization method of Dotori-muk muchim in Foodservice Operations(II) (단체급식소에서 이용되는 도토리묵 무침의 전처리 시 소독방법에 따른 품질 연구(II))

  • Kim, Heh-Young;Ko, Sung-Hee
    • Korean journal of food and cookery science
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    • v.21 no.5
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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.

Dynamics of Microbial Community of Aerobic Biofilm Reactor using Rhodococcus sp. EL-GT and Activated Sludge for Phenol Wastewater Treatment (페놀폐수 처리를 위한 Rhodococcus sp. EL-GT와 활성슬러지를 이용한 호기성 생물막 반응기의 미생물 군집 동태)

  • 박근태;원성내;손홍주;남귀숙;이재동;이상준
    • Journal of Environmental Science International
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    • v.10 no.3
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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).

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Assessment of indoor air micro-flora in selected schools

  • Katiyar, Vinita
    • Advances in environmental research
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    • v.2 no.1
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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.

Effect of Vacuum Packaging on the Microbial Change of Chicken during Storage

  • Kim, Jiyoun;Song, Kyung-Bin
    • Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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    • 2003.10a
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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.

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A Study on the Quality Depending on Sanitization method of Raw vegetables in Foodservice Operations( I ) (단체급식소에서 이용되는 식재료의 전처리시 소독방법에 따른 품질 연구( I ))

  • Kim Heh-Young;Go Seong Hui;Jeong Jin-Woong;Kim Ji-Young;Lim Yaung-iee
    • Korean journal of food and cookery science
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    • v.20 no.6 s.84
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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.

Effectiveness of the Verif $EYE^{TM}$ machine -vision technology for complying with reducing microbial indicator counts on beef carcasses

  • Lee, Jeong-Ah;Kim, Sa-Hyun;Lee, Sang-Koan;Kim, Gi-Cheol;Oh, Hye-Won;Jung, Tae-Nam;Lee, Yang-Soo;Jung, Chang-Jin;Jang, Won-Hyuck
    • Korean Journal of Veterinary Service
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    • v.30 no.2
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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.