• 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.

• Korean Journal of Poultry Science
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• v.32 no.3
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• pp.187-193
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• 2005

This study was carried out to investigate the effect of the bleeding times(30sec., 90sec., 150sec.) at slaughtering process on meat quality and storage properties of broiler. The redness$(a^{\ast}\;value)$ of skin, wing, leg muscle decreased at high bleeding time(150sec.). However, there was no significant difference in breast muscle. WHC(water holding capacity) of breast muscle decreased from $63.64\%$ at low bleeding time(30sec.) to $61.06\%$ at high bleeding time. TBARS(thiobarbituric acid-reactive substance) values were 0.18 mgMA/kg at the low bleeding time, 0.16 mgMA/kg at the middle bleeding time(90sec.) and 0.21mgMA/kg high bleeding time on 3 days of storage. Total aerobic plate counts(TPC) were $6.25logCFU/cm^2$ at the low bleeding time, $6.25logCFU/cm^2$ at the middle bleeding time and $6.53logCFU/cm^2$ at the high bleeding time. The TPC was increased as the bleeding time increased. In conclusion, meat color of chicken were acceptable when the carcasses were slaughtered at the high bleeding time.

• Korean Journal of Food Science and Technology
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• v.44 no.6
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• pp.743-749
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• 2012

Black soybean paste (BSP) is a bealmijang manufactured with barley flour and black soybeans. This study investigated the quality characteristics of BSP prepared with Bacillus subtilis HJ18-4 (HJ18-4). ${\alpha}$-Amylase and protease activities of BSP rapidly increased on day 6 and day 9, respectively, ($41.45{\pm}0.3-42.72{\pm}0.16$, $21.84{\pm}0.24-23.11{\pm}0.35unit/g$) after which the activities were constant or decreased slightly. Amino type nitrogen contents increased until day 23 ($173.78{\pm}3.51-195.63{\pm}1.51mg\;%$), whereas ammonia type nitrogen sharply decreased on day 9. On day 30, lactic acid bacteria counts were higher compared with the initial count ($7.91{\pm}0.05-8.17{\pm}0.02log\;CFU/g$). Meanwhile, B. cereus and total aerobic counts in HJ18-4 added BSP were lower than that in the control. These results implied that BSP could be edible after 30 days of fermentation, and the addition of HJ18-4 in meju could contribute to the safety of the black soybean paste by the inhibition of B. cereus growth.

• Journal of Bio-Environment Control
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• v.28 no.3
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• pp.265-272
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• 2019

The purpose of this study was to investigate the effects of LED and QD-LED (Quantum Dot) irradiation on seed germination, antioxidant ability, and microbial growth, during red radish (Raphanus sativus L.) sprouts cultivation. Irradiated light was blue, red, blue + red and blue + red + far red (QD-LED) lights, and the controls were a fluorescent lamp (FL), and dark condition. Germination rate of red radish was highest in the dark condition. The plant height and fresh weight of red radish sprouts that irradiated each light for 24 hrs after 7 days growing in dark condition, did not shown significantly difference among treatments. After 24 hrs of light irradiation, cotyledon green was best in blue + red light, and the red hypocotyl was excellent in blue light and QD-LED light. DPPH and phenol contents were high in dark and blue + red light treatment, and anthocyanin content was high in blue light and QD-LED light. Total aerobic counts were similar in all treatments and did not show bactericidal effect, whereas E. coli count was lowest in QD-LED light treatment, and yeast and mold counts were lowest in FL only treatment. Results suggest that when red radish seeds were germinated in dark condition and cultivated for 7 days as sprouts, and then treated with blue light or QD-LED light for 24 hrs, the seeds produced good quality red radish sprouts with greenish cotyledon, reddish hypocotyl, high anthocyanin content, and lower level of E coli contamination.

• Journal of Dairy Science and Biotechnology
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• v.24 no.1
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• pp.9-18
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• 2006

Total 150 packs of UHT milk and UHT-ESL milk, produced by different domestic milk companies, were compared at refrigerated and room temperature for 35 days in terms of microbiological qualities such as incidence date, number of incidence packs, and numbers of bacteria, and post-pasteurization contamination. Overall qualities of UHT-ESL milk were slightly better than that of UHT milk in relations to total bacteria in milk. No coliforms were detected in two groups of UHT milk samples after 35 days. Aerobic spores were more common in two brands of UHT milks stored in 20$^{\circ}$C than those in 7$^{\circ}$C, in which spores were broken out at 7 and 14 day. No incidences of thermoduric bacteria were founded until 14 days in two groups of UHT milks, but high level of counts (<300${\sim}$<3,000 CFU/ml) after 21 days at 20$^{\circ}$C and 40${\sim}$3,600 CFU/ml at 7$^{\circ}$C were detected, respectively. Psychrotrophic bacteria were higher in UHT milk than in UHT-ESL milk, in which began to detect at 28 days. No post-pasteurization contamination by salmonella spp. and staphylococcus aureus were found throughout the experimental periods. One may conclude that the shelf life of UHT milk under cold-chains system can be extended up to 21days, as long as UHT treated milk are filled in sterilized containers by aseptic packaging system.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.1
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• pp.65-71
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• 2007

Five different commercial chungkukjang powders (A$\sim$E) were compared based on their physicochemical, organoleptic and functional properties. The proximate composition of the five samples ranged from 6.07 to 8.54% in moisture, 15.31 to 27.07% in crude protein, 20.19 to 24.75% in crude lipid, 34.84 to 52.41% in carbohydrate, and 3.69 to 5.26% in ash. The pH of the samples ranged from 5.58 to 6.11, and Hunter's colors showed 70.01$\sim$77.22 for L value, 0.91$\sim$4.64 for a value and 23.72$\sim$31.00 for b value depending on the product. The microbial counts were 8.16$\sim$g.60 log CFU/g for aerobic bacteria, $\sim$4.16 log CFU/g for yeasts & molds, and 1.07$\sim$3.88 log CFU/g for coliforms. The contents of reducing sugars and amino-N were 1.89$\sim$2.41% and 2.83$\sim$7.31%, respectively. Free amino acids were mainly composed of glutamic acid, valine, leucine, phenylalanine, and lysine. The amounts of total phenolics and total flavonoids were 108$\sim$302 mg% and 2.73$\sim$9.41, respectively, with some variations in the products. However, the isoflavone contents, which were composed of genistein (63.26$\sim$217.16${\mu}g/g$), daidzein (58.24$\sim$166.65${\mu}g/g$), genistin (2.66$\sim$55.68${\mu}g/g$), and glycitein (12.26$\sim$17.82${\mu}g/g$), were apparently different per product. The sensory scores for color, smell, taste and overall preference for the five chungkukjang products, which were evaluated by panels in their 20's and 30's using 7-point scoring test, ranged from 3.20 to 4.05.

• Food Science of Animal Resources
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• v.32 no.3
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• pp.354-363
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• 2012

The study was conducted to determine bio-markers and establish shelf-life for eggs and egg products. The selected biomarkers were measured storage period according to samples (two months for table eggs and two weeks for whole liquid eggs) and five storage temperatures ($10^{\circ}C$, $15^{\circ}C$, $25^{\circ}C$, $35^{\circ}C$ and $45^{\circ}C$). The bio-markers for table eggs determined pH, acid value, VBN (volatile basic nitrogen), HU (Haugh unit), aerobic plate counts, coliform group, and Salmonella sp. The bio-markers for whole liquid eggs excluded HU in the bio-markers of eggs. The shelf-life of table eggs observed as 42 d at $10^{\circ}C$, 27 d at $15^{\circ}C$, 9 d at $25^{\circ}C$, 2 d at $35^{\circ}C$, and 1 d at $45^{\circ}C$ in sensory overall acceptability. The shelf-life of pasteurized whole liquid eggs observed as 7 d at $10^{\circ}C$, 3 d at $15^{\circ}C$, 2 d at $25^{\circ}C$, 1 d at $35^{\circ}C$, and less than one d at $45^{\circ}C$ in total plate count. The shelf-life of non- pasteurized whole liquid eggs observed as 4 d at $10^{\circ}C$, 2 d at $15^{\circ}C$, 1 d at $25^{\circ}C$, and less than 1 d at $35^{\circ}C$ and $45^{\circ}C$ in total plate count.

• Food Science of Animal Resources
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• v.28 no.2
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• pp.122-129
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• 2008

The antioxidant and antimicrobial activities of pork patties supplemented with medicinal herb extract mix were investigated. The medicinal herb extract powder was mixed at a ratio of 48.5:48.5:3.0 for Morus alba L, Lonicera flos, and Coptis chinensis, respectively. The pork was prepared and supplemented with medicinal herb extract mix (0, 0.5, 1, or 2%) and the antioxidant and antimicrobial activities were tested during storage at $4^{\circ}C$. The pH value decreased during cold storage at $4^{\circ}C$ for allsamples, however the pH of samples supplemented with herb extract mix rapidly decreased by days 5 and 10 ($p{\leq}0.05$). The total phenol content in the pork patties with herb extract mix was higher than in the control patties. The ABTS+ radical scavenging activities increased with increasing concentrations of herb extract mix from 0.5% to 2%. In addition, pork patties supplemented with herb extract mix showed an approximately 1 decimal reduction in total aerobic counts. Therefore, the addition of herb extract mix into pork patties increased the antioxidant activity and slightly improved the antimicrobial activity of pork patties during cold storage. However, the levels of added medicinal herb extract mix should be considered prior to its use in order to maintain proper sensory acceptance.

• Journal of Food Hygiene and Safety
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• v.21 no.1
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• pp.41-46
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• 2006

This study was carried out to survey the prevalence of foodborne pathogens in Sangshik products and their raw materials far the purpose of ensuring safety of those products in market, and establishing microbial regulatory standard. From 2002 to 2004, a total of 191 Sangshik products were purchased from market or mail-order sales, and major foodborne pathogens; E. coli, Salmonella, Staphylococcus aureus, Bacillus cereus, Clostridium perfringens, Listeria monocytogenes, Campylobacter jejuni, Yersinia enterocolitica, E. coli O157:H7, Vibrio parahaemolyticus were tested. B. cereus, C. perfringens and E. coli were detected from 29 samples (15.2%), 21 samples (11.0%) and 1 sample (0.5%), respectively. But other tested bacteria were not detected. For the identification of contamination source, 53 Sangshik ingredients were collected from 9 different manufacture factories. The results were similar with the Sangshik products. Aerobic plate counts were ranging from $1.0X10^3cfu/g\;to\;1.5X10^8cfu/g$. B. cereus was detected from 13 samples (24.5%), and counted as less than 100 cfu/g. C. perfringens were detected from 2 samples (3.8%), and counted as less than 100 cfu/g. Other foodborne pathogens were not detected except for B. cereus and C. perfringens. From the results, it was revealed that potential of microbial hazard by Sangshik was relatively low. However, it would be suggested that hygienic management and controling be needed for the prevention of growing contaminated pathogens and cross contamination during process and sale due to improper storage and management.

• Journal of Food Hygiene and Safety
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• v.31 no.5
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• pp.375-379
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• 2016

Atmospheric pressure plasma (APP) was applied to examine microbial safety and qualities of commercial Sunsik. APP was generated in a square-shaped plastic container (250 W, 15 kHz, ambient air) and dielectric barrier discharge plasma treatment was applied for periods of 0, 5, 10, and 20 minutes. The total aerobic bacterial count in the control was 4.44 log CFU/g. Under plasma treatment for 20 minutes, Sunsik samples inoculated with Bacillus cereus, B. subtilis, and Escherichia coli O157:H7 resulted in a reduction of bacterial counts by approximately 2.20, 2.22, and 2.52 log CFU/g, respectively. The pH of the sample was found to decrease after APP treatment. Although hunter color $L^*$ of Sunsik increased, $a^*$ and $b^*$ value decreased as a result of APP. Increasing the APP time also enhanced the peroxide value. Further, sensory evaluation revealed that APP decreased color, flavor, taste and overall acceptability. The results of this study indicated that APP treatment improved the microbial quality of Sunsik, although further studies should be conducted to reduce the deterioration of sensory quality induced by APP.