• Journal of Food Hygiene and Safety
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• v.37 no.4
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• pp.271-276
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• 2022

This study aimed to investigate microbial contamination of Dutch coffee in Gyeonggi province, South Korea. A total of 70 different Dutch coffee were purchased from an offline market (food service business operator). Two types of coffee were considered: "coffee made from food service business operator" and "coffee made from food manufacturer." The levels of total aerobic bacteria were 0.74-6.21 log CFU/mL in 15 samples and fungi were 0.70-4.00 log CFU/mL in 21 samples. Total aerobic bacteria was detected at higher levels in "coffee made from food service business operator" than in "coffee made from food manufacturer," and the difference was not significant. Three samples in "coffee made from food manufacturer" exceeded the standard for total aerobic bacteria. Escherichia coli, Coliform, and 12 types of foodborne bacteria were not detected in all samples. The extraction method detected no difference in cell counts of total aerobic bacteria and fungi. Therefore, to reduce microbial contamination of Dutch coffee, managing hygiene while maintaining the refrigeration temperature from the bean management stage to the sale process is crucial.

• Korean Journal of Veterinary Research
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• v.15 no.1
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• pp.83-91
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• 1975

A total of 119 raw milk samples from ten dairy farms were examined for total bacterial count, and 739 quarter milk samples of 118 dairy cows of 14 herds were examined for mastitis. The results obtained were as follows: 1. The mean of total bacterial counts of the 119 raw milk samples was 132,000 per ml. The total bacterial counts of 81 samples (68.1%) were under the standard of 100,000 per ml and those of the 38 samples (31. 9%) were over the standard. The number of bacteria showed a tendency to increase in summer. 2. One hundred and ninety five quarters (26.4%) of 98 cows (52.7%) were proved to be infected with mastitis. Clinical mastitis was found at 7 qtarters (3.5%) of 5 cows (5.0%). 3. Staphylococcus (44.9%) and Streptococcus (26.7%) were two main causative organisms of mastitis. Coliform bacteria (4.6%), Pseuedomonas spp. (4.6%), yeasts (1. 3%) and corynebacterium sp. (0.7%) were also isolated from the infected quarters. 4. The isolates were more sensitive to chloramphenicol ((96.1%), leukomycin (78.8%), streptomycin (75.5%) and tetracycline (72.4%). On the other hand, they were less sensitive to colistin (11.0%), oreandomycin (18.1%), sulfisoxazole (24.6%), penicilline (27.6%), kanamycin (43.3%) and erythromycin (49.7%). Especially the strains of Pseudomonas spp. isolated from the infected quarters were resistant to almost all the drugs examined.

• Fisheries and Aquatic Sciences
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• v.17 no.2
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• pp.197-201
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• 2014

This study was performed to identify and assess food hazards during dry laver processing. Samples including raw materials, intermediates, and finished products during dried-laver processing were collected from seven dried-laver processing facilities, and microbial analyses were conducted. Microbial levels such as total coliforms and total viable cell count (TVC) increased as the processing steps progressed. TVC and total coliforms ranged from <30 to $9.1{\times}10^7$ CFU/g and <18 to 27,600 MPN/100 g for intermediates and finished products obtained during dried-laver processing, respectively. However, no fecal coliform was detected in the samples. Additionally, food-borne bacteria including Bacillus cereus, Listeria monocytogenes, Salmonella sp., Staphylococcus aureus, and Vibrio parahaemolyticus were not identified in finished products. For heavy metal content, arsenic ranged from 30.18 to 39.05 mg/kg, mercury from 0.005 to 0.009 mg/kg, and cadmium from 0.076 to 0.318 mg/kg dry mass in all finished products. However, lead was not detected in samples tested in this study. In conclusion, dried-laver products were safe based on the levels of food-borne bacteria and heavy metal contents. However, it is important to reduce total viable cell counts and total coliforms during dried-laver processing.

• Journal of Food Hygiene and Safety
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• v.19 no.4
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• pp.209-216
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• 2004

Dry rehydratable film methods were compared to conventional methods for the enumeration of microorganisms in Korean traditional foods. Kimchi, doenjang, kochujang, kanjang, takju, sujeongkwa and sikhe were used as Korean traditional foods. $Petrifilm^{TM}$ aerobic count plate, $Petrifilm^{TM}$ coliform count plate, $Petrifilm^{TM}$ E. coli/coliform count plate, $Petrifilm^{TM}$ yeast and mold count plate and $Petrifilm^{TM}$ staph express count plate were compared to plate count agar, most probable number (MPN) for coliform, MPN for E. coli, potato dextrose agar and coagulase test, respectively. Regression analysis indicated that correlation coefficient values were 0.974-0.998, 0.913-0.995, 0.955-0.978, 0.968-0.986 and 0.998-0.999 for total aerobic bacteria, yeast and mold, coliform, E. coli and S. aureus, respectively. There were no significant differences between two methods, suggesting that $Petrifilm^{TM}$ plates can be used as an alternative to conventional method for the determination of microorganisms in Korean traditional foods.

• Journal of the Korean Applied Science and Technology
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• v.35 no.3
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• pp.807-815
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• 2018

This study was investigated the effect of dietary probiotic mixture on blood biomarkers, immune responses, caecal microorganism and productivity in broiler chickens under heat stress (HS). A total of 400 broiler chick males (Ross 308) were divided into four groups of 100 heads each, group C (control, room temperature $25^{\circ}C$), HS (heat stress $33^{\circ}C$) and HSP (HS plus probiotic mixture 500, 750 mg/kg of diet), respectively. Broiler body weight gain, feed intake, feed conversion ratio and immune organ weight increased in the HSP group compared to the HS group. The concentrations of blood IgG and lymphocyte were increased in the HSP group compared to the HS group, and the heterophil:lymphocyte (H:L) ratio, corticosterone concentration and mortality were low. Lactobacillus in the cecum increased in the HSP group compared to the HS group, but was lower in Escherichiacoli (E. coli), coliform bacteria and aerobic bacteria. These results indicate that feeding probitic mixture including three strains such as B. subtilis, S. galilaeus and Sphingobacteriaceae to broiler exposed to heat stress can improve production with lowering mortality by improving immune response and microbial balance.

• Journal of the Korean Applied Science and Technology
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• v.35 no.3
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• pp.787-796
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• 2018

This study was conducted to investigate the effects of probiotic mixture on fecal ammonia, caecal microorganism, immune response, egg quality and production in layer under heat stress (HS).A total of four hundred 50 week olds Hy-Line Brown layers were randomly divided into four groups of 100 heads each: C (control, room temperature $25^{\circ}C$), HS (heat stress $33^{\circ}C$), PM (HS plus probiotic mixture 500, 750 mg/kg of diets). Egg production, egg quality, spleen weight, blood IgG and lymphocyte concentrations were increased in the PM group compared to the HS group, while mortality, the heterophil:lymphocyte (H:L) ratio, and corticosterone levelswere significantly decreased. Lactobacillus was increased in the PM group compared to the HS group, but E. coli, coliform bacteria and aerobic bacteria were significantly reduced. Fecal ammonia production was significantly increased in the HS group compared to the PM group. In conclusion, the results of this study that these mixed probiotics can reduce the heat damage of the summer laying hens and can be an effective nutritional strategy to reduce odor generation from feces, and to improve egg quality and laying production through immune response and caecal microbial balance.

• Food Science of Animal Resources
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• v.35 no.4
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• pp.441-448
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• 2015

Blanching beef for use in home meal replacements (HMR) is an important process that determines the final quality of the beef after the cooking process. Thermal pretreatment also minimizes the change in quality during the main cooking process or storage. In this study, beef samples were washed and sliced, then treated by immersion in boiling water (1-10 min), steaming (1-10 min), or pan-frying in oil (30-240 s). The color after each thermal treatment showed higher L* and b* values and lower a* values compared with the raw beef, except for the pan-frying thermal treatment. The total color difference (∆E) and pH value were significantly increased by panfrying (p<0.05). There was no significant difference in the shear force of the beef samples, except for the sample pan-fried for 210 s. The nutritional content of beef was measured as the moisture, protein, fat, and ash contents, which were 69.96, 16.64, 3.49, and 1.13%, respectively, in raw beef. After thermal treatment, the crude protein and fat contents were increased, whereas the moisture and ash contents decreased. The mineral content, including Na, Mg, Fe, and Ca was highest after pan-frying. The heat treatment decreased microorganisms in all the samples. The total bacteria count in raw beef was 4.5-4.7 Log CFU/g, whereas the bacteria count decreased to 2.2-2.8 Log CFU/g after blanching. Thermophilic bacteria, coliform, mold, and yeast not detected in any thermally treated sample.

• Food Science of Animal Resources
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• v.38 no.2
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• pp.338-349
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• 2018

The objective of this study was to investigate comparison of physicochemical, microbiological, and sensory characteristics of Hanwoo eye of round by various packaging methods [wrapped packaging (WP), modified atmosphere packaging (MAP), vacuum packaging (VP) with three different vacuum films, and vacuum skin packaging (VSP)] at a small scale. Packaged Hanwoo beef samples were stored in refrigerated conditions ($4{\pm}1^{\circ}C$) for 28 days. Packaged beef was sampled on days 0, 7, 14, 21, and 28. Physicochemical [pH, surface color, thiobarbituric acid reactive substances (TBARS), and volatile basic nitrogen (VBN) values], microbiological, and sensory analysis of packaged beef samples were performed. VP and VSP samples showed low TBARS and VBN values, and pH and surface color did not change substantially during the 28-day period. For VSP, total viable bacteria, psychrotrophic bacteria, lactic acid bacteria, and coliform counts were lower than those for other packaging systems. Salmonella spp. and Escherichia coli O157:H7 were not detected in any packaged beef samples. A sensory analysis showed that the scores for appearance, flavor, color, and overall acceptability did not change significantly until day 7. In total, VSP was effective with respect to significantly higher $a^*$ values, physicochemical stability, and microbial safety in Hanwoo packaging (p<0.05).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.5
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• pp.489-494
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• 2014

This study determined the effect of packaging and electron beam irradiation on the quality of dried Undaria pinnatifida. Samples were air or vacuum packaged and irradiated at 7 kGy. The dried Undaria pinnatifida had total viable cells and coliform counts of 5.51 and 4.40 log CFU/g in total, respectively, and counts of 5.56 and 4.19 log CFU/g in surface. These counts were reduced by 2-4 log cycles after irradiation. Irradiation increased the lightness and yellowness of the dried Undaria pinnatifida, but not the redness. In the sensory evaluation, there were no significant differences among samples. Therefore, electron beam irradiation improves the microbial safety and quality of dried Undaria pinnatifida.

• Journal of environmental and Sanitary engineering
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• v.1 no.1 s.1
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• pp.59-67
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• 1986

This sanitary survey was carried out to investigate the bacteriological contamination of cooking utensils and foods of moving tavern in eight sample sites of Seoul area. The results of survey were as follows: 1. The counts by means of total bacteria in cooking utensils and food samples by standard plate count method were as follow: $5.6\times10^5$ per gm in dishcloth, $3.1\times10^6$ per ml in dishwater. In food samples, $5.4\times10^5$ per gm in meat was higher than other samples. 2. The average counts total coliform and fecal coliform in samples by MPN method were as follow: $3.4\times10^4$ MPN per 100ml, and $1.3\times10^2$ MPN per 100ml in chopping board, $6.1\times10^4$MPN per gm and $1.0\times10^2$ MPN per gm in dishcloth, $1.8\times10^5$ MPN per 100ml and $6.1\times10^2$ MPN per 100ml in dishwater. In food samples, $3.1\times10^4$MPN per gm and $2.0\times10^2$ MPN per gm in meat was higher than other samples. 3. The counts by means of Pseudomonas in samples by MPN method were as follow: $2.8\times10^3$ MPN per 100ml in chopping board, $4.7\times10^3$ MPN per gm in dishcloth $5.6\times10^3$ MPN per 100ml in dishwater. In food samples, $2.4\times10^3$ MPN per gm in shellfish was higher than other samples. 4. Isolation cases of Food poisoning organisms from samples were as follow: Staphylococci was detected 9 cases $(17.6\%)$ in chopping board, 7 cases $(13.6\%)$ in dishcloth. In food samples, 9 cases $(25.7\%)$ in meat, 1 case $(4\%)$ in fish samples. Salmonella was detected 2 cases $(3.9\%)$ in dishwater, 1 case in meat samples.