• Journal of Food Hygiene and Safety
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• v.22 no.1
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• pp.57-62
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• 2007

Microbiological, pH, and sensory evaluations on pork tender-loins treated with potassium sorbate (PS) during storage at $4^{\circ}C$ were assessed. Treatments of 0.5-2.0% PS for 10 min effectively (P < 0.05) inhibited the growth of aerobic plate counts (APC) and gram-negative bacterial counts (GNC) compared to those of controls for 9 days at $4^{\circ}C$, respectively. Results of this investigation demonstrate that antimicrobial activity on APC and GNC in all treatments enhanced by increasing concentrations of PS during storage at $4^{\circ}C$. pH values of pork tender-loins treated with PS gradually increased by storage of 6 days at $4^{\circ}C$. Sensory data showed that 0.5-1.0% PS treatments were quite close in odor and appearance compared to fresh controls. Results indicated that pork tender-loins treated with 1.0% PS for 10 min could extend shelf-life to 9 days during refrigerated storage at $4^{\circ}C$ without adversely affecting sensory quality.

• Food Science of Animal Resources
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• v.22 no.1
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• pp.44-49
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• 2002

The effect of citric acid and sodium chlorite(NaClO$_2$) mixtures at 100, 200 and 500 ppd(w/v) on the growth of microorganisms from broiler thigh surface was investigated. Absorbance and aerobic plate counts(APC) of inoculated nutrient broth refrigerated storage at 4∼5$^{\circ}C$ were measured after each additive was added. APC on thigh surface after immersion in each selected solution was enumerated during storage at 4∼5$^{\circ}C$ Absorbance of all citric acid and sodium chlorite mixture(0:100, 25:75, 50:50, 75:25 and 100:0, w/w) except 200 and 500 ppm of 100:0 at Day 0 were lower than the control during storage (p<0.05). And higher concentration of mixture tended to have lower absorbance. APC on thigh surface treated with 500 ppm citric acid and sodium chlorite mixture at 50 : 50 and 75 : 25 ratio were lower than others (p<0.05). Similar antimicrobial activity of additives was found in nutrient broth and on broiler thigh surface.

• KSBB Journal
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• v.17 no.4
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• pp.350-356
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• 2002

Low density polyethylene(LDPE) film was fabricated with the addition of benzoic acid, or/and JP which contained water-soluble silica adsorbed a natural antimicrobial compounds. The used antimicrobial compounds were isolated from culture broths of methylotropic actinomycetes strains MO-16 and MO-17 which was newly isolated from soils. An antimicrobial compound retained antimicrobial activity after heat treatment at 121$^{\circ}C$ for 5 min. JP, which obtained from Japan as a antimicrobial agent, showed antimicrobial activity in the concentration of 100 mg/mL. The silica LDPE film revealed the growth inhibition of total aerobic bacteria in packaged minced pork compared with commercial film and of E. coil on a contained agar plate. In the storage testing of various packaged foods at room temperature for 30 days, the film showed excellent preservation compared with commercial film in case of small tomato and Agaricus bisporus.

• Food Science and Preservation
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• v.7 no.1
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• pp.12-18
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• 2000

As am economical and effective way of antimicrobial film fabrication , antimicrobial agents were coated on the LDPE film with a binder mediu. the fabricated films were then applied tomodified atmosphere packaging of fresh strawberries. A binder of polyamide was selected for the coating medium, based on the stability in water. 1% grapefruit seed extract-coated film showed the antimicrobial activity on the plate media against EScherichia coli, Staphylococcus aureus, bacillus subtilis , Bacillus cereus, Leuconostoc mesenteroides, Micrococcus flavus, Saccharomyces cerevisiae, while one with 10% Coptis chinesis extract inhibited only M. 림편 and one coated with 10% rheum palmatum extract did not inhibit any of 10 strains tested. The packages of fresh strawberries by using antimicrobial agents-coated films created the gas compositions of O2 1.4-5.5% and CO2 5.7-7.9%, and contributed to reduced growth of total aerobic bacteria and yeast/molds on the produced. However, their lower microbial count was not correlated directly with the reduced decay of the fruits.

• Food Science of Animal Resources
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• v.36 no.5
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• pp.594-600
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• 2016

This study aimed to examine the microbial contamination levels in livestock products at retail stores. Beef, pork, and chicken samples from raw materials and final products were obtained between January and December 2015. All homogenized meat samples (25 g) were tested for the aerobic plate count (APC), coliform count (CC), and Escherichia coli count (E. coli). The highest APCs in meat samples, by month, at retail shops were obtained in September, followed by July, May, and October (p<0.001). However, APC was the highest in summer and the lowest in winter (p<0.001). Average APCs for beef, pork, and chicken samples were 2.90, 3.19, and 3.79 Log CFU/g, respectively (p<0.05). A comparison between different months revealed that, CC levels in meat samples ranged from 0 to 1.13 CFU/g, and the highest CC was obtained in August (p<0.001). By season, the highest CC was found in the summer, followed by autumn, and spring (p<0.001). All meat samples were negative for E. coli. The average log₁₀APC and CC for all samples was 3.10 and 0.37 Log CFU/g, respectively. Furthermore, there was a direct correlation between the season and coliform presence (p<0.001). There was also a positive correlation between the APC and CC (r = 0.517, p<0.001). The microbiological APCs for livestock products were in most cases below 10⁶ CFU/g.

• Food Science and Biotechnology
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• v.15 no.1
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• pp.152-157
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• 2006

Enterobacter sakazakii, designated as an unique microbial species in 1980, may cause bacteremia, necrotizing enterocolitis and infant meningitis. The distribution and the thermostability of E. sakazakii in unprocessed ready-to-eat (RTE) agricultural products of 252 and in 25 powdered infant formulas (PIF) were analyzed. Eighty one, 50, 43, and 47% of brown rice, pumpkin, potato, and carrot samples, respectively, had aerobic plate counts (ARC) in the range of 5 log CFU/g or more. Almost all the other products sampled had APC of approximately 2 log CFU/g. Fifty three, 75, 67, and 68% of banana, pumpkin, soybean, and carrot had Enterobacteriaceae counts approximating 3 log CFU/g. Sixty six percent of the brown rice tested had Enterobacteriaceae counts approximating 5-6 log CFU/g. E. sakazakii was isolated from 3/25(12%), 4/23(17%), 1/24(4%), and 1/27(4%) of PIF, brown rice, laver, and tomato samples, respectively. D-values were 3.52-4.79 min at 60 and $D_{60}-values$ were similar as the isolates reported. Thermal inactivation of four thermovariant E. sakazakii strains during the rehydration of PIF with hot water were investigated. At $50^{\circ}C$, the levels of E. sakazakii decreased one log CFU/g for 4-6 min and thereafter the levels remained stable for 20 min. At $60^{\circ}C$, inactivation by about 2 log CFU/g occurred for 20 min. Therefore, the unprocessed agricultural products might be a source of contamination for PIF when used as an ingredient after drying and pulverization. Rehydration of PIF for infant feeding with a water temperature of $60^{\circ}C$ rather than $50^{\circ}C$, as recommended by the manufacturers, may be helpful in the reduction of potential E. sakazakii risk.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.5
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• pp.655-660
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• 2006

The purpose of this study was to analyze the microbiological hazards of prepared foods, raw materials, utensils and workers' hands and to evaluate cross-contamination of bacteria in foodservice establishments. Aerobic plate counts, coliforms, E. coli, E. coli O157:H7, Salmonella spp., Staphylococcus aureus and Listeria monocytogenes were tested. According to the microbiological evaluation, there were many cases of contamination of bacteria. Staphylococcus aureus was detected in chicken stew (Korean type), Japchae, Bibimbap and Kongnamul-muchim at the A foodservice establishment and Jwieochae-jorim at the B foodservice establishment. E. coli was detected in Ojingeochae-muchim at the C foodservice establishment. E. coli O157:H7, Salmonella spp. and Listeria monocytogenes were not detected in any of the tested samples. Critically, microbiological contamination of raw materials, utensils and workers' hands could result in contamination of prepared foods, thus, attention needs to be given to sanitation of raw materials, workers' hands and utensils to reduce or eliminate contamination of bacteria.

• Food Science of Animal Resources
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• v.18 no.2
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• pp.107-114
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• 1998

This study aimed for the examination of quality characteristics and safety of potassium sorbate-free meat products. Therefore, experiments were carried out on the frankfurter sausage and pressed ham, which were stored at 4 and 30$^{\circ}C$ for up to 40 days. The potassium sorbate concentrations of the frankfurter sausage and pressed ham obtained from local market ranged from 1.087 to 1.449g / kg, which were below the permitted value as prescribed in the Korean Hygienic Regulation. At the 0 day the total aerobic bacterial counts of frankfurter sausage and pressed ham were in the level of around 103.0 and 103.4 CFU / g, respectively. However, they were prominently increased after 20 days at 4$^{\circ}C$ and 10 days at 30$^{\circ}C$ to higher than 105 CFU / g. After 30 days the counts were increased to 106.5 and 107.2 CFU / g, respectively. The growth curve of lactic acid bacteria was shown to be similar with that of total bacteria. the counts of lactic acid bacteria of the products stored at 4$^{\circ}C$ were 101∼102 CFU / g lower than those stored at 30$^{\circ}C$. Coliform bacteria was not detected in both of the products stored at 4$^{\circ}C$ even after 40 days storage, but after 10 days at the 30$^{\circ}C$. No significant differences in the microbial counts examined in this study were observed between frankfurter sausage and pressed ham. The biochemical tests on the isolated colonies from Clostridein agar showed no presence of Clostridium botulinum and Clostridium perfringens in the meat products examined. The pH of frankfurter sausage and pressed ham at the beginning was about 6.6, which level was maintained relatively constant during the storage at 4$^{\circ}C$, but it was increased after decrease to about 5.5 during the storage at 30$^{\circ}C$. TBA value was increased slightly till 30 days, but after that time increased sharply. VBN value was increased slowly during the whole storage, but it was more than 30 mg% for the samples stored at 30$^{\circ}C$.

• Journal of Oral Medicine and Pain
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• v.18 no.1
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• pp.73-82
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• 1993

To investigate the changes in aerobic and facultative anaerobic oral microflora during remission-induction chemotherapy in patients with acute myeloid leukemia, 10 consecutive patients were studied during a period of 28 days. One day before, during and after the induction therapy, patients were given 10% Betadine solution for mouthrinses after breakfast and kept from eating and drinking. After 3 hours, paraffin-stimulated whole saliva was obtained for 2 minutes and transported to the laboratory. The samples were dispersed and homogenized by use of vortex mixer for 20 seconds. From these samples 10-fold serial dilutions (from 10-1 through 10-3) were prepared. Each dilution of 0.1 ml was plated on duplicate set of one nonselective medium (Blood agar) and four selective media (Sabourauds dextrose agar, Mannitol salt agar, Mac-Conkey agar, SF medium ) using applicator woods. All agar plate were incubated at 37$^{\circ}C$ for 48 hours. The total number of microorganisms was calculated and the percentage distribution of the various microorganisms from each specimen was drawn. 1. The salivary flow rate decreased by 66%, going from 5.38 ml/2min to 1.81 ml/2min over two days during the chemotherapy. 2. The total number of microorganisms in saliva increased by 22%, going from 4.88$\times$105/ml to 6.00$\times$105/ml over two days during the chemotherapy. 3. The salivary flow rate and the total number of microorganisms in saliva were recovered within 28 days after the chemotherapy. 4. The quantitative alteration in oral Enterobacteria, Enterococci, Staphylococci, Cndida during the chemotherapy had no statistical significance. 5. In saliva of the patients with acute myeloid leukemia who ahd intraoral ulcer, Enterobacteria was quantitatively predominent. Our study suggests that chemotherapy-induced transient xerostomia may induce acute oral infection. Consequently, the use of saliva substitute, the removal of intraoral infection source and the consistent oral hygiene care seem to be required to avoid the transmission of potential pathogenes in this group of patients.

• KSBB Journal
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• v.15 no.6
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• pp.600-604
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• 2000

Low density polyethylene(LDPE) film was fabricated with the addition of synthetic ceramic which contained a natural antimicrobial agents. The antimicrobial agents used were isolated from culture broths of methylotropic actinomycetes strains MO-16 and MO-17, and Streptomyces sp. No. 31, which was newly isolated from soils as an antifungal agent. Four-day old culture broth of Streptomyces sp. No. 31 showed strong antifungal activity against Aspergilus niger, a test strain, and retained antimicrobial activity after heat treatment at $121^{\circ}C$ for 15 min. The ceramic LDPE film reduced the growth of total aerobic bacteria in packaged minced pork compared with commercial film. The film revealed a 40 to 50% growth inhibition of E. coli on a contained agar plate. In the storage testing of various packaged foods at room temperature for 30 days, the ceramic LDPE film showed excellent preservation compared with commercial film.