• Korean Journal of Food Science and Technology
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• v.39 no.6
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• pp.663-668
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• 2007

This study evaluated the microbial, nutritional, and rheological changes in potatoes, during storage at room, low, and freezing temperatures for 6 months. No significant changes in total aerobic plate counts were observed for any of the samples in the assessment of microbiological quality changes. For the 4 types of frozen potatoes, yeasts and molds were not found until 24 weeks. The sugar contents of the potatoes stored at room and low temperature ($10^{\circ}C$) increased during the first 4 weeks of storage, but then decreased rapidly thereafter; while those in the frozen potatoes did not change significantly throughout the 48 weeks. The vitamin C, B1, and B2 contents of the potatoes stored at room and low temperature had decreased significantly after 4 weeks of storage, however, the levels in the frozen potatoes did not change rapidly. The weight, volume, and hardness of the frozen potatoes changed much less as compared to the potatoes stored at room and low temperature over the 48 weeks of storage. Finally, the cohesiveness of all the samples, except for the frozen mashed potatoes, did not change during storage.

• Korean Journal of Agricultural Science
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• v.25 no.2
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• pp.168-175
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• 1998

To evaluate the storage characteristics of pheasant meat products, contents of aerobic, anaerobic and food poisoning bacteria as well as VBN were measured during storage at various temperatures. 1. During the storage Escherichia coli and food poisoning bacteria including Salmonella, Shigella and Staphylococcus were not detected from any of the pheasant meat products. 2. Total plate counts of aerobic and anaerobic bacteria increased with storage temperature, showing more than $10^6CFU/g$ of most pheasant meat products within 5~10 days of storage at $20^{\circ}C$ and $30^{\circ}C$. However, frank sausage, loin ham, pressed ham and salad showed less than $10^5CFU/g$ in 20~30 days of storage at $20^{\circ}C$. 3. When stored at $10^{\circ}C$, smoked product, electric roasted product and pressed ham showed the bacterial counts of more than $10^4CFU/g$ within 10 days of storage. Frank sausage, loin ham and salad, however, showed less than $10^3CFU/g$ in 10 days of storage at $10^{\circ}C$. 4. VBN contents of smoked product, electric roasted product and frank sausage exceeded edible limit of 20 mg%, showing more than 40 mg% and 80 mg% within 5 days and 10 days, respectively, of storage at $10^{\circ}C$. In contrast, loin ham, pressed ham and salad had the VBN of less than 20 mg% in 10 days of storage at $10^{\circ}C$. In summary, while pheasant meat products in general appear to be prone to microbial growth, loin ham and salad are thought to have a longer storage period than others, showing about 10 days of preservation at $10^{\circ}C$. Products other than loin ham and salad are suggested to be stored frozen or refrigerated at below $10^{\circ}C$.

• Korean Journal of Veterinary Service
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• v.35 no.4
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• pp.313-319
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• 2012

Consumer's preference and microbial inspections on fresh raw beef were carried out to understand the actual market status in Gwanju, Korea. Over 15 questions on questionnaire by 1,111 randomly selected respondents between April and May in 2011, results showed 65.5% positive on eating fresh raw beef, 63.8% negative on good hygiene condition of fresh raw beef, and 72.5% positive on the secure of the hygiene-safety for priority program, respectively. For microbial inspections, a total of 302 samples were collected from fresh raw beef purchased from slaughterhouse (n=122), transport (n=69) and consumer (n=81) stage, from lettuce (n=30) at consumer stage. The aerobic plate count (APC), E. coli count and food borne bacteria such as Salmonella spp., Listeria monocytogenes, Staphylococcus(S.) aureus and E. coli O157:H7 were tested in the samples. As results, the level of count on APC of fresh raw beef ranged $6{\times}10^1{\sim}1.8{\times}10^5CFU/g$ from slaughterhouse, $2{\times}10^2{\sim}8.3{\times}10^5CFU/g$ from transport stage and $1{\times}10^2{\sim}4{\times}10^5CFU/g$ from consumer stage. The level of count on E. coli of fresh raw beef ranged $1{\sim}9{\times}10^1CFU/g$ from slaughterhouse, $1{\sim}7{\times}10CFU/g$ from transport stage and $1{\sim}5.5{\times}10CFU/g$ from consumer stage. In total, 26 S. aureus were isolated, 10 (14.5%) from fresh raw beef at transport stage, 12 (14.8%) from fresh raw beef and 4 (13.3%) from lettuce at consumer stage. Enterotoxin of S. aureus was not detected among 26 isolates. All S. aureus isolates were typed using a DiversiLab$^{TM}$ rep-PCR system for genetic similarity test, showing over 95% of genetic relationship amon isolates.

• Membrane Journal
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• v.15 no.2
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• pp.114-120
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• 2005

The purpose of this study is to obtain practical information about membrane coupled $ A_2O$ system for muncipal wastewater treatment. A flat-plate microfiltration (MF) module with a pore size $0.25\;{\mu}m$ was submerged into the aeration basin and treated water was filtrated through the membrane by continuous suction with low pressure. The system was operated with synthetic wastewater to find operational parameters of internal recycle ratio and maximum MLSS showing best water quality and long-term stability. The internal recycle was defined as type 1 for aerobic to anoxic tank and type 2 for anoxic to anaerobic tank, respectively When the flux was maintained at $0.015\;m^3/m^2/hr$ (15 LMH) with 2Q type 1 internal recycle ratio, the optimal operational setting were 10 internal recycle ratio for type 2 and maximum MLSS of 11,000 mg/L among tested conditions. At this condition, removal efficiencies of BOD, CODcr, T-N and T-P showed $97.3\%,\;94.2\%,\;64.0\%,\;63.0\%$, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.4
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• pp.637-642
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• 2010

Pre-treatment steps of fresh produce as Saengshik raw materials are followed by initial clean-up, dipping, primary washing, and cutting. Hypochlorous acid solution was applied in the dipping step to reduce natural microflora. Also, procedures were changed by cutting, dipping and then primary washing, and the efficacy of hypochlorus acid was evaluated. Potatoes, carrots, kales, and angelicas were submerged in water or 100 ppm of hypochlorous acid for 5 min. After initial clean-up, the aerobic plate counts of potatoes, carrots, kales and angelicas were 4.7, 5.3, 5.6, and 5.7 log CFU/g, respectively. When samples were submerged into water, it only reduced the population of natural microflora by 0.2 to 1.1 log CFU/g, whereas when treated with hypochlorous acid, it reduced the population by 0.5 to 2.8 log CFU/g. Reductions of natural microflora in green leafy vegetables were more highly achieved than bulbs such as potatoes and carrots. However, the numbers of natural microflora were increased after cutting step. To control the cross contamination at the cutting process, the process was changed as follows: initial clean-up, cutting, dipping in hypochlorous acid, and then primary washing. It showed effective reduction of the population by 2.3 to 3.2 log CFU/g. Hypochlorous acid solution could be useful as a sanitizer for surface washing of fresh vegetables.

• Culinary science and hospitality research
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• v.20 no.6
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• pp.200-210
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• 2014

The purpose of this study was to investigate the quality changes and contamination of microorganisms such as Escherichia coli, mold and yeast in cherry tomatoes during storage at different temperatures, gas composition and periods(7 and 14 days). This study determined pH, color change and the growth pattern of microorganisms in cherry tomato during storage at $5^{\circ}C$, $10^{\circ}C$ and $15^{\circ}C$. According to the results, pH level was a little raised with storage period. On average, $L^*$, $a^*$ and $b^*$ value of cherry tomato were irregular value of increase and decrease of all gas packaging with storage period. In regard of the types of microorganism, aerobic count plate, coliform count, mold and yeast were detected when cherry tomatoes were stored at $5^{\circ}C$, $10^{\circ}C$ and $15^{\circ}C$ during storage for 14 days. Equally, all microorganisms of cherry tomato were irregular with storage period and complex gas packaging. However, this study determined that packaging with a higher $CO_2$ concentration than $O_2$ concentration can reduce growth of microorganism. These studies can be used as primary data for determining the optimal complex gas to storage enlargement.

• Food Science of Animal Resources
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• v.24 no.1
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• pp.29-36
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• 2004

Changes in quality characteristics and shelf-life of two types of grill sausage manufactured by using pork hind leg and re-pasteurized after packaging were investigated during storage at 5$^{\circ}C$ and 10$^{\circ}C$ up to 30 days. The total aerobic plate counts(APC) of N rnberger style grill sausage(NGS) and vegetable added grill sausage(VGS) were initially 3.08 and 3.57 log$\sub$10/CFU/$\textrm{cm}^2$, respectively, and gradually increased during storage time. After 30 days, the APC of NGS stored at 5$^{\circ}C$ and 10$^{\circ}C$ maintained relatively low at the levels of 5.32 and 6.58 log$\sub$10/CFU/$\textrm{cm}^2$, respectively. However, the APC of VGS exceeded the level of 8 log$\sub$10/CFU/$\textrm{cm}^2$ after 30 days at 5$^{\circ}C$ and after 20 days at 10$^{\circ}C$. pH was decreased with storage period, however it tended to increase after 30 days. The values of TBA and VBN for both sausages tended to increase with storage time, and this trend was pronounced at 5$^{\circ}C$ rather than at 10$^{\circ}C$. The purge loss was apparently increased in the VGS compared to the NGS sample as the storage period extended. According to the sensory evaluation, the marketing values of grill sausages stored at 5$^{\circ}C$ and 10$^{\circ}C$ were maintained until day 20 for NGS and day 14 for VGS, respectively.

• Food Science of Animal Resources
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• v.28 no.3
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• pp.289-294
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• 2008

The influence of gamma irradiation with low doses (0.5, 1.0, and 1.5 kGy) on the meat quality of chicken breast was determined for 6 days of storage at $4^{\circ}C$. The pH of irradiated chicken was lower than that of the control at day 1 (p<0.05), while no difference was found among irradiation at different doses. Drip loss was higher in irradiated chicken with doses of 0.5 and 1.0 kGy compared to the control at day 1 and day 3 (p<0.05). Lightness (L) at day 1 and day 6 was increased due to irradiation (p<0.05). Redness (a) increased with irradiation doses of 1.0 and 1.5 kGy at day 1 and day 3 (p<0.05). However, no significant differences were found in yellowness (b). The number of aerobic plate count of irradiated chicken during storage was significantly lower than the control (p<0.05). E. coli and coliforms were not detected after irradiation at any dose. Also, irradiation doses of 1.0 and 1.5 kGy significantly reduced volatile basic nitrogen (VBN) and 2-thiobarbituric acid reactive substances (TBARS) values compared to the control during storage (p<0.05). These results suggest that low dose gamma irradiation can be useful to extend the shelf life of chicken breast during cold storage.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.16 no.2_3
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• pp.43-51
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• 2010

The changes in quality and shelf life of smoked pork belly according to packaging methods were investigated during storage at $5{\pm}1^{\circ}C$ up to 12 days. Three packaging treatments including air-containing packaging (AC), vacuum packaging (VP), and packaging incorporated with oxygen scavenger (OS) were applied in this experiment. In all treatments, the initial total aerobic plate count (TPC) was 2.4 log cfu/g which was increased with storage period. The rapidest increase of TPC was observed in the AC samples, followed by OS and VP. The VP samples showed inhibiting effects on the growth of Pseudomonas spp. and coliforms over the storage. The TBA values were increased in the order of AC-OS-VP. The VBN values of the VP and OS samples tended to be increased slower than the AC samples during the storage. According to the sensory evaluations, the point of losing marketability in the raw AC, OS, and VP samples was determined to be the day 8, 10, and 12, respectively. However, the evaluations for the cooked samples showed the AC and OS samples preserved the marketing value until the day 10 and 12, while the VP samples until the day 12 except in the parameter of texture. In conclusion, it was found that the most appropriate packaging method for preserving the quality and extending the shelf life of chilled smoked pork belly is vacuum packaging.

• Journal of Food Hygiene and Safety
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• v.26 no.2
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• pp.154-159
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• 2011

Inadequate food handling and poor hand hygiene playa major role in the occurrence of foodborne diseases. The objective of this study was to find out if the level of microbial contamination on the hands of food preparers varies by time during their working period. This study focused on the contamination of aerobic plate count, total and fecal coliforms, Escherichia coli, Staphylococcus aureus, and Salmonella spp. Sampling from left hand and right hand of twenty food preparers was done with glove-juice method at every two hours during their work. Microbiological testing was conducted according to the Food Code of Korea. The microbiological load on the hands was changed over time. Samples taken from their hands before work and at 8 hours showed higher levels of bacteria than those taken at 2, 4, and 6 hours during work and/or after work (p < 0.05). The contamination levels of microorganisms were consistently higher in right hand than in left hand. Poor hand hygiene practices were indicated by the positive results for total and fecal coli forms, E. coli, S. aureus, and Salmonella spp. on the hands of some food preparers. This study indicates food preparers' hands can be a vehicle of pathogen during their work. The results of this study emphasize the importance of hand hygiene education and training targeting the food preparers.