• Food Science of Animal Resources
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• v.29 no.1
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• pp.47-54
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• 2009

Predictive modeling was applied to study the growth of microorganisms related to spoilage in frankfurter sausage containing various levels of dietary fiber (0, 1, 2, and 3%) from rice bran and to estimate its shelf-life. Using the Baranyi model, total viable cells, anaerobic and psychrotrophic bacteria were measured during 35 days of cold storage ($<4{\pm}1^{\circ}C$). The lag times (LT) demonstrated by control and treatment groups were 6.28, 623, 6.24, and 6.25 days, respectively. The growth rate of total viable cells in each group were 0.95, 0.91, 0.92, and 0.91 (Log CFU/g/day), respectively. The anaerobic and psychrotrophic bacteria had lower initial ($y_0$) and maximal bacterial counts ($y_{max}$) than total viable cells. Also, the anaerobic and psychrotrophic bacteria possessed lower growth rate and longer lag time than total viable cells. The estimated shelf-life of frankfurter containing rice bran fiber by the growth rate of total viable cells was 7.8, 7.9, 7.9, and 7.7 days, respectively. There were no significant differences in shelf-life as a function of fiber content. In other words, the addition of dietary fiber in sausage did not show the critically hazardous results in growth of microorganism. The 12 predictive models were then characterized by high $R^2$, and small RMSE. Furthermore, $B_f$ and $A_f$ values showed a very close relationship between the predictive and observed data.

• Korean Journal of Veterinary Service
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• v.15 no.2
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• pp.215-225
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• 1992

To estimate pollution status of livestock wastewater on four piggeries and one abattoir in Taegu area, physicochemical water analysis such as pH, suspended solid(SS), biochemical oxygen demand(BOD) and chemical oxygen demand(COD), and bacteriological examinations such as number of total viable cells and number of coliform with or without antibiotic resistance were carried out. The results obtained were as follows : The pH values of raw sewage ranged from 9.0 to 7.2 that of the effluent treated was lowed to 5.6~7.7. The SS values of raw sewage ranged from 5,275ppm to 120ppm and those of the efflunet decreased to 162~30ppm. The BOD values of raw sewage ranged 6,200ppm to 120ppm and those of the effluent treated decreased to 111 ~80ppm. The COD values of raw sewage ranged from 5,725ppm to 298ppm and those of the effluent decreased to 137~76ppm. The total viable cells of raw sewage ranged from $8.5{\times}11^{11}$/ml to $9.9{\times}10^7$/ml, those of the effluent decreased to $5.6{\times}10^6{\sim}4.2{\times}10^8/ml.$ The total coliforms of raw sewage ranged from $5.5{\times}10^9$/ml to $1.3{\times}10^5$/ml, those of the effluent decreased to $3.6{\times}10^4ml{\sim}9.0{\times}10^6$/ml. The incidence of streptomycin resistant coliforms was the highest(1.8~66.7%), and followed by tetracycline(1.7~64%), kanamycin(9.3~50.l%), ampicillin(0.06~45.5%) and chloramphenicol(14.3~33.5%) to total coliforms of raw sewage. The incidence of antibiotic resistant coliforms of raw sewage in farms ranged from 3.4~66.7% and that of abattoir's was 0.06% to 14.3%. Antibiotic resistant coliform counts of raw sewage ranged from 1.3$\times$10$^{8}$ /ml to 3.9$\times$10$^3$/ml, those of the effluent decreased to $3.0{\times}10^1{\sim}2.3{\times}10^5/ml$.

• Journal of Food Hygiene and Safety
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• v.38 no.1
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• pp.19-25
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• 2023

Addition of spice for inhibition of bacterial growth in ground chicken meat was investigated. The ground chicken meat approximately contained 72.98±0.15% moisture, 23.37±0.46% crude protein, 1.00±0.03% crude fat, and 1.90±0.03% ashes. Addition of rosemary showed the maximum bacterial inhibition, followed by garlic and mustard. The inhibitory effect increased with the addition of a greater quantity of spices. The optimal added concentration of spices for inhibition of total viable cell and proliferation of Escherichia coli in ground chicken meat was 2%, 4%, and 1.2% for rosemary, garlic, and mustard, respectively. The growth inhibition of total viable cells and E. coli differed during storage period for MixA (97.4%) > rosemary (96.9%) > MixB (96.3%) > garlic (53.7%) > mustard (33.3%). The addition of sterilized garlic to ground chicken meat showed that the total viable cells was low at 2.6-3.0 log CFU/g on the 0-day and 2.4-3.2 log CFU/g on the 9-day, and the number decreased as the storage lengthened. Non-sterilized garlic treatment showed a higher number of total viable cells than the control group, and this increased with elapse of storage time. The number of E. coli, was low at 0.4-1.0 log CFU/g on the 0-day and 0.5-1.5 log CFU/g on the 9-day for the sterilized group, and the change during the storage showed a similar trend for the total viable cells. In conclusion, the microbial safety of ground chicken meat products was improved by various mixed applications of rosemary, garlic, and mustard.

• The Plant Pathology Journal
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• v.29 no.4
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• pp.374-385
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• 2013

Environmental stresses induce several plant pathogenic bacteria into a viable but nonculturable (VBNC) state, but the basis for VBNC is largely uncharacterized. We investigated the physiology and morphology of the copper-induced VBNC state in the plant pathogen Ralstonia solanacearum in liquid microcosm. Supplementation of $200{\mu}M$ copper sulfate to the liquid microcosm completely suppressed bacterial colony formation on culture media; however, LIVE/DEAD BacLight bacterial viability staining showed that the bacterial cells maintained viability, and that the viable cells contain higher level of DNA. Based on electron microscopic observations, the bacterial cells in the VBNC state were unchanged in size, but heavily aggregated and surrounded by an unknown extracellular material. Cellular ribosome contents, however, were less, resulting in a reduction of the total RNA in VBNC cells. Proteome comparison and reverse transcription PCR analysis showed that the Dps protein production was up-regulated at the transcriptional level and that 2 catalases/peroxidases were present at lower level in VBNC cells. Cell aggregation and elevated levels of Dps protein are typical oxidative stress responses. $H_2O_2$ levels also increased in VBNC cells, which could result if catalase/peroxidase levels are reduced. Some of phenotypic changes in VBNC cells of R. solanacearum could be an oxidative stress response due to $H_2O_2$ accumulation. This report is the first of the distinct phenotypic changes in cells of R. solanacearum in the VBNC state.

• The Korean Journal of Food And Nutrition
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• v.21 no.2
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• pp.176-183
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• 2008

This study examined the anti-microbiological effects of chlorine treatment on the surface of fresh fruits, in order to improve microbiological safety in school foodservice operations. Non-peeled fruit(strawberries) and peeled fruit(bananas) were treated with different concentrations of chlorinated water and rinsing numbers, followed by microbiological testing. The fruits were immersed at different concentrations of chlorinated water(0 ppm, 50 ppm, and 100 ppm) and durations(3 min and 5 min), and were then rinsed with tap water(one time, two times, or three times). The total viable cell counts of both the strawberries and bananas ranged from $10^3$ CFU/g to $10^4$ CFU/g, and coliform levels ranged from $10^2$ CFU/g to $10^3$ CFU/g. As the chlorine concentration, immersion time, and rinsing number increased, anti-microbiological activity increased. The largest microbial reduction was shown with immersion for 5 min in 100 ppm chlorinated water and three rinsings. In the strawberries, this treatment reduced the initial population of total viable cells and coliforms by 3.29 log CFU/g and to an undetectable level, respectively, no total viable cells or coliforms were detected on the banana surface following this treatment. However, after a sterilization treatment with immersion for 5 min in 50 ppm chlorinated water and three rinsings, the total viable cell counts and coliform counts of the strawberries and bananas decreased to acceptable levels, based on the microbiological standards for ready-to-eat foods. Overall, it was shown that the sterilization treatment of 50 ppm chlorinated water, soaking for 5 min, and three rinsings provided an effective reduction in surface microbes, and enhanced the microbiological safety of the fruit.

• Journal of Food Hygiene and Safety
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• v.1 no.1
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• pp.47-50
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• 1986

Sanitary condition for raw milk in Korea was investigated in this study. It is hoped that the information will be used for reference in future endeavors of study in the field of public health and food sanitation in Korea. The results were summerized as follows: 1) The viable cell counts of bacteria in raw milk were tend to be increased under the various atmospheric temperature, and the correlation coefficient between temperature and total viable cells was r=+0.921(p<0.01). 2) The correlation coefficient between methylene blue reduction time test and viable cell counts of bacteria in raw milk was r=-0.799(p<0.01). 3) The relationship between total solid rate(%) and milk fat rate(%) was highly significant level as r=+0.745(p<0.01). 4) Highly significant correlation coefficient was r= +0.945(p<0.01) between milk fat and protein rate in raw milk.

• Korean Journal of Microbiology
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• v.52 no.3
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• pp.313-318
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• 2016

Bacteria in the viable but nonculturable (VBNC) state fail to produce colonies on routine bacteriological media, but are still alive in the state of very low metabolic activity. The aim of the present study was to induce the VBNC state of the Edwardsiella tarda using sea water microcosm under starvation conditions at $10^{\circ}C$ and to investigate resuscitation of the VBNC cells in temperatures changed from 10 to $25^{\circ}C$, with and without additives. E. tarda entered into the VBNC state within about 42-84 days of incubation in the microcosm. Throughout this period, the total cell counts as determined using acridine orange direct counting remained near the original inoculum level of ${\sim}10^8cells/ml$. The live cell counts measured with direct viable counting, on the other hands, declined to ${\sim}10^4cells/ml$. When the VBNC cells were incubated with addition of yeast extract, fish muscle extract or serum at $25^{\circ}C$, the ratios of resuscitated samples were 37%, 23%, and 37%, respectively. The characteristics of resuscitated E. tarda were consistent with those of the original E. tarda. When the resuscitated E. tarda were intraperitoneally injected into olive flounders, all fishes died within 5 days, indicating that the VBNC E. tarda might retain its pathogenic potential. Therefore, E. tarda under starvation conditions in the winter enter into the VBNC state and the VBNC E. tarda cells resuscitated at summer and autumn seawater temperature are considered to be pathogen continuously to olive flounder on the southern coast of Korea.

• International Journal of Oral Biology
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• v.35 no.1
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• pp.1-5
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• 2010

Human fibroblasts that maintain the structural integrity of connective tissues by secreting precursors of the extracellular matrix are typically cultured with serum. However, there are potential disadvantages of the use of serum including unnatural interactions between the cells and the potential for exposure to animal pathogens. To prevent the possible influence of serum on fibroblast cultures, we devised a serum-free growth method and present in vitro data that demonstrate its suitability for growing porcine fetal fibroblasts. These cells were grown under four different culture conditions: no serum (negative control), 10% fetal bovine serum (FBS, positive control), 10% knockout serum replacement (KSR) and 20% KSR in the medium. The proliferation rates and viabilities of the cells were investigated by counting the number of cells and trypan blue staining, respectively. The 10% FBS group showed the largest increase in the total number of cells ($1.09\;{\times}\;10^5\;cells/ml$). In terms of the rate of viable cells, the results from the KSR supplementation groups (20% KSR:64.7%; 10% KSR: 80.6%) were similar to those from the 10% FBS group (68.5%). Moreover, supplementation with either 10% ($3.0\;{\times}\;10^4\;cells/ml$) or 20% KSR ($4.8\;{\times}\;10^4\;cells/ml$) produced similar cell growth rates. In conclusion, although KSR supplementation produces a lower cell proliferation rate than FBS, this growth condition is more effective for obtaining an appropriate number of viable porcine fetal fibroblasts in culture. Using KSR in fibroblast culture medium is thus a viable alternative to FBS.

• Journal of the East Asian Society of Dietary Life
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• v.14 no.2
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• pp.131-134
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• 2004

This study was carried out to investigate the shelf life of Shepherd's purse(Capsella bursa-pastoris) Kimchi during fermentation at 1$0^{\circ}C$. Capsella bursa-pastoris was treated without or with blanching. The viable cells of lactic acid bacteria(LAB) of raw and blanched Kimchi after fermentation for 15 days at 1$0^{\circ}C$ were 7.91 log CFU/mL and 6.4 log CFU/mL, respectively. The viable cells of LAB of Capsella bursa-pastoris Kimchi at 1$0^{\circ}C$ were lower in the blanched one when compared to the raw one. The pH of raw Kimchi was lower than that of the blanched one during fermentation for 25 days at 1$0^{\circ}C$. The viable cells of total bacteria of the blanched Kimchi were lower than that of non-blanched one during fermentation at 1$0^{\circ}C$. The ascorbic acid and chlorophyll contents decreased more in the blanched Kimchi when compared to that treated without heat. The sensory quality of the blanched Kimchi was a little inferior to that treated without heat during fermentation.

• Korean journal of food and cookery science
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• v.20 no.6 s.84
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• pp.561-567
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• 2004

The purpose of this study was to investigate the effect of Paecilomyces japonica mycelia(PJM) on pH, titrable acidity and microbiological qualify of Jeungpyun(fermented rice cake). Jeungpyun prepared with $0\~\%$ of PJM stored at $5^{\circ}C\;and\;20^{\circ}C$ for 4 weeks and 7 days respectively. Before fermentation of Jeungpyun dough, viable cells of total bacterial counts(TBC), yeasts and lactic acid bacteria(LAB) were $6.0\~9.8\times10^6,\;5.3\~9.0\times10^6,\;5.4\~8.5\times10^6\;CFU/g$, respectively. During the fermentation of dough, viable cells of TBC, yeasts and LAB increased $0.3\~0.4$ log cycle and pH was decreased whereas acidity increased as the progress of fermentation. Total viable cells in Jeungpyun before storage were $5.0\times10^1\;CFU/g$. During storage of Jeungpyun, TBC, yeasts and LAB of control group increased 2.6, 2.4, 2.1 log cycle at $5^{\circ}C$ and 4.8, 4.6, 4.5 log cycle at $50^{\circ}C$, respectively, when reached at maximum level. Major microflora of Jeungpyun was composed of yeasts and LAB during fermentation of dough and storage at $5^{\circ}C\;and\;20^{\circ}C$. Addition of PJM, inhibited the growth of microorganisms, the changes of PH and titrable acidity of Jeungpyun during storage at both of $5^{\circ}C\;and\;20^{\circ}C$. From these results, the addition of PJM extended the shelf-life of Jeungpyun during storage at $5^{\circ}C\;and\;20^{\circ}C$.