• Journal of Food Hygiene and Safety
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• v.8 no.3
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• pp.135-140
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• 1993

Dried fishes such as dried pollack, dried sliced squid, dried white bait, dried anchoy) and dried cod used to cook Korean traditional foods were airpacked in polyethylene tube and irradiated with 7 kGy of gamma-ray source. The effect of gamma irradiation on microbial growth in dried fishes was investigated during storage at ambient temperature for 12 months. The total aerobic bacteria in the control group were contaminated by $3.9{\times}10^{3}\;cells/g$ in dried pollack, $5.6{\times}10^{5}\;cells/g$ in dried sliced squid, $1.2{\times}10^{5}\;cells/g$ in dried white bait, $1.2{\times}10^{4}\;cells/g$ in dried anchovy and $1.2{\times}10^{4}\;cells/g$ in dried cod and 7 kGy irradiation could eliminate the bacteria and also reduce aerobic bacterial load to 1~3 log cycle and no apparent growth of microorganisms occurred during storage. Molds in the control group were contaminated by $4.0{\times}10^{2}\;cells/g$ in dried pollack, $$1.3{\times}10^{2}\;cells/g$ in dried sliced squid, $2.5{\times}10^{2}\;cells/g$ in dried white bait, 90 cells/g in dried anchovy and $2.0{\times}10^{2}\;cells/g$ in dried cod, respectively. 7 kGy irradiation could sterilize the molds and the growth of molds of nonirradiated samples were slightly decreased during storage. Yeasts in the control group were contaminated by $1.4{\times}10^{3}\;cells/g$ in dried poUack, 75 cells/g in dried sliced squid, $1.1{\times}10^{3}\;cells/g$ in dried white bait, 50 cells/g in dried anchovy, $1.6{\times}10^{2}\;cells/g$ in dried cod, respectively and irradiation could sterilize the yeasts and growth of yeasts was slightly decreased in dried pollack and dried white bait but increased in order of dried anchovy, dried cod and dried sliced squid. Coliforms in all sample were sterilized by irradiation and its growth was decreased during storage except dried anchovy.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.12
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• pp.1830-1841
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• 2012

We investigated the changes in microbial and physicochemical characteristics of the raw materials of Saengsk (brown rice, barley, carrot, potato, Angelica utilis Makino and kale) during storage after treatment with slightly acidic electrolyzed water (SAEW). To confirm the antimicrobial effects of the treatment washing solutions as well as the physicochemical changes in chromaticity, we stored the raw materials of Saengsik for 5, 10, 15, 20, 25 and 30 days at storage temperatures of 4, 10, 15, 20, 25 and $30^{\circ}C$ in a shelf-life study. The effects of microbial inhibition were higher in carrot treated with SAEW than in that treated with NaOCl, as indicated by a 1.75 log CFU/g reduction. Moreover, a 1.54 log CFU/g reduction of total coliforms was achieved in brown rice in response to SAEW treatment, which was higher than NaOCl treatment at all storage temperatures and periods. The lightness, redness and yellowness values of the raw materials of Saengsik were not significantly affected by SAEW treatments, except for Angelica utilis Makino and kale, whereas SAEW treatment resulted in decreased chromaticity values when compared to the NaOCl treatment. Overall, there was a significant difference (p<0.05) between the efficacy of the SAEW and NaOCl treatments. These results indicate that washing with SAEW is an effective method to reduce the microorganisms and enhance the shelf-life of raw materials of Saengsik; therefore, it can be effectively used to sanitize ingredients of Saengik without affecting the other properties during storage.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.10
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• pp.1343-1356
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• 2008

The evaluation of microbiological quality for school food samples collected from 19 selected middle and high schools located in Seoul was undertaken. Eighty-nine food samples consisting of 38 non-pretreated vegetables, 13 pre-washed and cut vegetables, 9 meats and poultry, 3 fish and shellfish, 7 dried fish, and shellfish and 20 processed foods were collected. Aerobic plate count, total coliforms, and Escherichia coli (E. coli ) were detected using $Petrifilm^{TM}$, and the food-borne pathogens were screened by multiplex PCR with species-specific primer sets. Sequentially, the quantitative and confirmative test of the food-borne pathogens were carried out with the selective media and biochemical kits. The contamination of coliform counts was observed on the pre-washed vegetables ($3.4{\sim}4.3\;log\;CFU/g$) and meats ($2.2{\sim}4.3\;log\;CFU/g$). Also, the cooked foods were heavily contaminated with coliform, ranging from 1.0 to $5.5\;log\;CFU/g$. E. coli counts were found in 16 raw and cooked food samples, exceeding the microbiological standards for the guideline of safety management for school foods. Through PCR detection, B acillus cereus was detected in 32 raw and cooked foods, and quantitatively found in pre-washed carrot, radish, and pan-broiled dried shrimp and filefish ranging from $2.3{\sim}3.6\;log\;CFU/g$, respectively. E. coli O157:H7 was detected on frozen pork sample and was confirmed with API kit. Campylobacter jejuni was found in 3 ready-to-eat type vegetables. Vibrio parahaemolyticus were found in 4 pre-washed vegetables and 2 cooked foods, indicating unsatisfactory quality based upon the microbiological standards of ready-to-eat vegetables and cooked foods by Korea Food and Drug Administration. Salmonella spp. was detected in frozen chicken sample and confirmed by API kit and latex antisera agglutination.

• Journal of Food Hygiene and Safety
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• v.4 no.2
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• pp.119-132
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• 1989

Gamma irradiation as a new physical treatment was applied to comparative investigates with a conventional ethylene oxide fumigant on the microbiological and physicochemical qualities of selected spices and dry vegetables such as powdered red pepper, black pepper, welsh onion, onion, garlic, carrot, korean cabbage and instant ramyon soup. The microorganisms contaminated in the sample, including total viable count, thermophilic bacteria, aerobic spore and fungi counts between the $10^4\;to\;10^6/g$ range. Coliforms were found only in black pepper and welsh onion powder as the $10^2\;to\;10^3/g$ level. A radiation dose of 7 to 10 KGy were sterilized completely to the contaminated microorganisms, while ehthylene oxide (E.O.) fumigation reduced of them to the $10^3/g$ level. An optimum dose of irradiation was less detrimental than E.O. fumigation to the physicochemical properties of the sample. Sensory evaluation after three months of storage at room temperatures showed that the overall acceptability of irradiated sample was higher than that of the non treated control as well as E.O. fumigated samples. Comparison gamma irradiation with E.O. gas treatment showed that E.O. treatment was less effective than radiation in cotrolling microbial contamination of spices and vegetables.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.2
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• pp.224-230
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• 2006

Microbial contamination levels and legal preservative appropriation in child foods sampled from the neighborhood of elementary schools were investigated. Contamination levels of total aerobic bacteria in seasoned dried fish slices, bread and snacks, sausages, sugar products and dumplings were $1.70\~6.91,\;1.40\~6.66$, 4.50, $3.48\~5.88$, and $4.79\~4.82\;log_{10}$ CFU/g, respectively. Coliforms in four kinds of foods except for dumplings were $2.30\~6.60,\;4.22\~~5.98$, 2.00, and $2.78\;log_{10}$ CFU/g, respectively. Yeasts and molds in those foods were $0.10\~4.23,\;1.66\~4.91,\;1.46\~1.91,\;1.56\~4.26$, and $1.12\~1.84\;log_{10}$ CFU/g, respectively. S. aureus was isolated in $18\%$ of seasoned dried fish slices ($1.00\~2.84\;log_{10}$ CFU/g), $33\%$ of bread and snacks ($1.70\~1.79\;log_{10}$ CFU/g), $50\%$ of sausages ($3.28\;log_{10}$ CFU/g), $22\%$ of sugar products ($2.16\~2.88\;log_{10}$ CFU/g), and $100\%$ of dumplings $(1.18\~3.31\;log_{10}\;CFU/g)$ B. cereus was isolated in $21\%$ of seasoned dried fish slices $(0.70\~2.48\;log_{10}\;CFU/g)$, $50\%$ of bread and snacks $(0.70\;log_{10}\;CFU/g)$, and $11\%$ of sugar products $(0.30\;log_{10}\;CFU/g)$. Both E. coli and Salmonella spp. were not isolated in all samples. Preservative was only labeled on four products among 15 products but preservative on 13 products including 4 products haying an indication of preservative were not detected. Moreover, $0.30\%$ of sorbic acid was detected in one of Squid products . The results of this study indicated that the hygienic level of child foods in Gyeonggi and Incheon was very poor and need to be improved.

• Food Science of Animal Resources
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• v.31 no.1
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• pp.100-106
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• 2011

The physicochemical characteristics of chicken breast were determined to identify the optimal ratio of $CO_2$ and $N_2$ to maintain chicken breast quality during cold storage for 6 d. The mixing ratios of $CO_2$ and $N_2$ were 20:80, 40:60, 60:40, and 80:20, respectively. The pH of the chicken breast packed with 80% $CO_2$ and 20% $N_2$ was lower than that of the control on day 1 (p<0.05). The lightness ($L^*$) of the breast increased with increasing $CO_2$ during storage (p<0.05), whereas no difference was found for redness ($a^*$) and yellowness ($b^*$). A lower volatile basic nitrogen level was found for chicken breasts exposed to higher $CO_2$ levels. Furthermore, lipid oxidation of the chicken breast packed with $CO_2$ decreased with increasing $CO_2$ level, and 40% $CO_2$ significantly reduced 2-thiobarbituric acid reactive substances (TBARS) values on days 1 and 6. The total number of microbes was reduced in chicken breast exposed to more than 40% $CO_2$ during storage days 3 and 6 (p<0.05); however, Escherichia coli was not affected by $CO_2$ level. Coliforms of chicken breast were reduced in the 40% $CO_2$ level on storage day 3. Moreover, tray-packed chicken breast exposed to 40% $CO_2$ did not collapse. These results suggest that 40% $CO_2$ and 60% $N_2$ were the optimal conditions for packaging chicken breasts during cold storage.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.10
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• pp.1225-1233
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• 2017

The aim of this study was to evaluate the microbial inhibitory activity and physicochemical quality of fresh carrot juice prepared with different environmentally-friendly washing methods during low temperature storage. Individual and combined treatments with sodium bicarbonate (baking soda, $NaHCO_3$) and citric acid were applied to carrots for 10 min. Tap water and 50 ppm of sodium hypochlorite (NaOCl) were used as the control. Combined treatment of 1% $NaHCO_3$ and 1% citric acid significantly reduced total aerobic counts and coliforms. In addition, combined treatment of 1% $NaHCO_3$ and 1% citric acid inhibited microbial growth for 7 days at $4^{\circ}C$ and $10^{\circ}C$ in a shelf-life study. There were no significant differences among the sanitizers in terms of $^{\circ}Brix$, acidity, pH, and color. Changes in physicochemical quality were not significantly different by sanitizer but were affected by storage temperature. These results indicate that washing with combined treatment of 1% $NaHCO_3$ and 1% citric acid is an effective method to inhibit the microbial population and maintain physicochemical quality. Therefore, combined treatment of 1% $NaHCO_3$ and 1% citric acid can be effectively used to sanitize and prepare carrot juice without affecting other properties.

• Korean Journal of Food Science and Technology
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• v.45 no.1
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• pp.104-110
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• 2013

This study assessed hazards at the harvest stage of strawberry farms which may cause risk to humans. A total of 216 samples were collected from 6 strawberry farms (soil culture farms: A, B, C; nutriculture farms: D, E, F) located in Western Gyeongnam. The collected samples were subjected for sanitary indicator bacteria (aerobic plate count, coliforms and Escherichia coli), major foodborne pathogens (E. coli O157:H7, Listeria monocytogenes, Salmonella spp., Staphylococcus aureus and Bacillus cereus), and fungi. The levels of APC and coliform in the soil culture farms were 1.0-6.9 and 0.4-4.6 log CFU/g (leaf, mL, hand or 100 $cm^2$), respectively. The samples obtained from the nutriculture farms were contaminated with the levels of 0.8-4.9, and 0.2-2.6 log CFU/g (leaf, mL, hand or 100 $cm^2$) of APC and coliform. However, E. coli was not detected in any samples. In major foodborne pathogens, S. aureus was detected at the level of ${\leq}$3.3 log CFU/hand in workers' hand samples and B. cereus was detected at the levels of 0.4-4.1 log CFU/g (hand or 100 $cm^2$) in soil, plants and workers' hygiene. L. monocytogenes, E. coli O157:H7 and Salmonella spp. were not detected. Fungi were detected at the levels of 1.0-5.2 and 0.2-4.4 log CFU/g (leaf, mL, hand or 100 $cm^2$) in soil culture and nutriculture farms, respectively.

• Korean Journal of Food Science and Technology
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• v.38 no.1
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• pp.121-127
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• 2006

Microbial and nutritional characteristics of Kwangchun shrimp Jeotgal (salt-fermented shrimp) were assessed. Total mesophilic bacteria, coliforms, and S. aureus counts in Kwangchun shrimp Jeotgal were 3.48-5.42, 2.22-2.95, and 0.58-2.51 $log_{10}CFU/g$, respectively. Yeast and mold were detected only in Ohjeot (1.99 $log_{10}CFU/g$) and Yookjeot (1.47 $log_{10}CFU/g$). B. cereus, L. monocytogenes, Vibrio spp. and E. coli were not detected in Kwangchun shrimp Jeotgal, which contained abundant macrominerals (Ca, Mg, Na, K), with Na showing highest content. Palmitic acid content was higher than those of other saturated fatty acids. Eicosapentaenoic acid and docosahexaenoic acid contents were higher than those of other poly unsaturated fatty acids. Results showed Kwangchun shrimp Jeotgal is safe microbiologically with abundant nutritional components.

• Food Science and Preservation
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• v.17 no.5
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• pp.586-594
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• 2010

We evaluated changes in the microbiological quality and safety of food items (vegetables, seaweed, and processed food) supplied to elementary school food services to evaluate the distribution/delivery system. Pretreated vegetables, seaweed, and processed food were delivered to schools in refrigerated (${\leq}10^{\circ}C$) vans that made several delivery stops before arriving at the schools. During the distribution stage, total plate and coliforms counts were: bellflower roots $7.6{\times}10^5-6.7{\times}10^6$ and $5.8{\times}10^4-5.2{\times}10^5$ CFU/g; blanched bracken $4.5{\times}10^3-2.1{\times}10^5$, $5.0{\times}10^3-1{\times}10^4$ CFU/g; onion $1.2{\times}10^4-1.4{\times}10^4$, $5.0{\times}10$ CFU/g; soybean sprouts $9.6{\times}10^4-6.3{\times}10^7$ and $1.1{\times}10^3-1.2{\times}10^7$ CFU/g; soybean curd < $10-9.7{\times}10^5$ and < $10-2.3{\times}10^5$ CFU/g; and starch jelly < $10-3.8{\times}10^3$ and <10 CFU/g. Bacillus cereus < $10-4.1{\times}10^2$ CFU/g, Escherichia coli $1.0{\times}10-2.0{\times}10$ CFU/g, and Staphylococcus aureus $1.3{\times}10^2-4.1{\times}10^2$ CFU/g were detected on peeled bellflower, whereas B. cereus < $10-4.1{\times}10^2$ CFU/g, Listeria monocytogenes $1.0{\times}10-4.5{\times}10^2$ CFU/g, and S. aureus $1.8{\times}10^2-4.5{\times}10^2$ CFU/g, were detected on soybean sprouts. Most food items were double-wrapped in vinyl and placed in corrugated cardboard boxes prior to delivery, but the boxes, when placed in vans, were not segregated from other food items being delivered to schools and other destinations.