• Korean Journal of Food Science and Technology
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• v.31 no.5
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• pp.1345-1348
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• 1999

The utility of a bioluminescence adenosine triphosphate(ATP) assay method for estimating bacterial levels in mackerel(Scomber japonicus) was investigated. Mackerel was stored at $1^{\circ}C$ throughout 10 days and its RLU(relative light unit) and APC(aerobic plate count) was determined. The ATP bioluminescence assay was validated during the storage of 32 samples, resulting in an agreement between the ATP assay and standard plate count methods of over 90% credibility. Therefore, ATP bioluminescence assay was considered as a rapid and near real-time means in estimating the microbial load on mackerel skin.

• Journal of Food Hygiene and Safety
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• v.12 no.1
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• pp.47-54
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• 1997

Fried vegetable mix, fried fish mix and fried chicken which prepared as convenient style at traditional market in Chonju were collected and evaluated their chemical composition, lipid and microbial changes during storage at different temperaturefor confirming those fried food stability. The POV and AV of oil in samples and total bacterial count during storage at 5, 15, 20 and 3$0^{\circ}C$ were monitered. The POV, AV and total bacterial count tested of each sample, shelf-life can be suggested as within 1 day at 3$0^{\circ}C$, 2~3 days at 15~2$0^{\circ}C$ and over 5 days at 5$^{\circ}C$.

• Food Science of Animal Resources
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• v.18 no.1
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• pp.27-34
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• 1998

This study was carried out to evaluate of the microbial and sensory quality of ready-made hamburger and sandwich. Initial total plate count of hamburger for establishment A and B were 1.2$\times$102 cfu / g and 3.4$\times$102 cfu / g, respectively, and for establishment C was 7.9$\times$104 cfu / g. After 48 hour storage at 1$0^{\circ}C$, total plate count of hamburger for establishment A and B increased to 1.2$\times$104 cfu / g and 6.8$\times$103, respectively, and for establishment C increased to 1.2$\times$107 cfu / g. Initial total plate count of sandwich for establishment A and B were 3.2$\times$102 cfu / g 7.9$\times$102 cfu / g, respectively, and for establishment C was 1.1$\times$105 cfu / g. After 48 hour storage at 1$0^{\circ}C$, total plate count of hamburger for establishment A and B increased to 8.1$\times$103 cfu / g and 2.3$\times$104, respectively, and for establishment C increased to 4.4$\times$108 cfu / g. No E. coli, Salmonella, Vibrio, and Staphylococcus aureus were detected under simulated storage conditions. There was no significant changes in pH, acid value, and volatile nitrogen number under simulated conditions. In sensory evaluation of hamburger and sandwich, sensory score was lowered by increase of total plate count.

• Food Science and Biotechnology
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• v.15 no.5
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• pp.773-777
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• 2006

Growth of Bacillus cereus was assessed during the storage of seasoned soybean sprouts at 0,5, 10, and $15^{\circ}C$. No lag time in its growth curve was observed and thus the specific growth rate of B. cereus in the exponential growth phase was estimated for bootstrapped microbial count data. The distribution of the specific growth rate could be explained by the BetaGeneral distribution function, and temperature dependence was described by the Ratkowsky square root model. The temperature dependence of the growth could be successfully incorporated into the differential equation of microbial growth to predict the B. cereus count on the seasoned soybean sprouts under fluctuating temperature conditions. Safe shelf lives with different probabilities to reach $10^5\;CFU/g$ were presented at four different temperatures, considering the variation in initial contamination and specific growth rate by the Monte Carlo method and 2-step bootstrapping, respectively. Safe shelf lives defined as the time with a probability of less than 0.1% of reaching the critical limit, were 13.4, 5.2, 3.6, and 2.8 days at 0, 5, 10, and $15^{\circ}C$, respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.5
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• pp.711-715
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• 2005

One of the prerequisites for the successful implementation of industrial-scale goat kefir production is to understand the effects of different kefir grains and culture conditions on the microbial and chemical properties of the goat kefir. Thus, the objectives of the present study were to evaluate the characteristics of kefir grains in Taiwan on the microbial and chemical properties of goat milk kefir, as well as to understand the influence of culture conditions on production of medium chain-length triglycerides (MCT). Kefir grains were collected from households in northern Taiwan. Heat-treated goat milk was inoculated with 3-5% (V/W) kefir grains incubated at 15, 17.5, 20 or 22.5$^{\circ}C$ for 20 h, and the microflora count, ethanol content, and caproic (C6), caprylic (C8), and capric acid (C10) levels measured at 4 h intervals. Our results indicate that incubation with kefir grains results in 10$^6$-10$^7$ CFU/ml microflora count and 1.18 g/L of ethanol content at 20 h of fermentation. Incubation with 5% kefir grain at 20-22.5$^{\circ}C$ produces the highest MCT levels.

• Proceedings of the Korean Society of Food Hygiene and Safety Conference
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• 1996.06a
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• pp.33-33
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• 1996

Interests in the field of rapid methods and automation in microbiology have been growing steadily on an international scale in recent years. International meetings concerned this problem have been held in elsewhere in the world countries since the past twenty years. But, unfortunately in the field of microbial examination in food hygiene, this problem have not yet been developed so much as in the field of clinical microbiology. Today, I would like to introduce you here present aspects of rapid and automation technologies, those which are manly carrying in milk and meats industries. My illustration will be given recent improved technologies using automatic apparatus and instruments along with process of microbial count procedure. Recent direct microbiological counting system (ChemeScan \ulcorner) as real time ultrasensitive analysis created by Cheminex Ltd., France is now most evolutional instrument to provide direct microbial counts, down to one cell, within 30 minutes. The results from these evaluations how a good correlation between the ChemScan system and the standard plate count method. This system will be successful application for not only in the field of pharmacology but also food microbiology. In addition, current identification of microbes by sophisticated instruments suitable for food microbiology, one of which Biology is manual system (BIOLOG\ulcorner), provides reference-level capability at a modes price. For the manual system, the color reactions in the microplate are read by eye and manually keyed into personal computer. Species identification appears on the computer screen within seconds, along with biotype patterns, a list of closely related species, and other useful statistics. In present this is useful application for microbial ecology and epidemiological survey. RiboPrinter system newly produced by DuPont is now focusing among microbiologists in the world, and is one of the biggest microbial characterization system using a DNA-based approach. The technology analyzer is bacterial culture for its genetic fingerprint or riboprint pattern. Finally Bio-cellTracer system for automatic measurement of fungal growth and Fukitori-Maseter, a Surface Hygiene Monitoring Kit by using swabe procedure in food processing environment are briefly illustrated in this presentation.

• Korean journal of food and cookery science
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• v.16 no.2
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• pp.99-111
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• 2000

The purpose of this study was to assess the qualities of cook/chilled soy sauce-glazed soybean curd with various packaging conditions as a trial to develop health-oriented convenience foods. The effects of three packaging methods, linear low density-polyethylene (LLD-PE), top sealing, and modified atmosphere packaging(MAP) on the shelf-life of HACCP-based cook/chilled soy sauce-glazed soybean curd were evaluated during 20 days of chilled storage in terms of time-temperature, microbiological (total aerobic plate count, psychrotrophic plate count, coliform, and fecal coliform count), chemical(pH and peroxide value(POV)), and sensory evaluation. The results of microbiological and chemical analyses were within the limits of the microbial and chemical standards for all phases after cooking. No significant differences were detected in microbial counts of the samples for all three packaging methods. However, sensory evaluation indicated that the top sealing and MAP methods showed a longer shelf-life than LLD-PE packaging. Recommended shelf-life of the product was 12 days for LLD-PE packaging, and 16 days for both top sealing and MAP. In conclusion, MAP was considered as the most effective packaging method for assuring microbial and sensory quality of this cook/chilled product.

• Korean journal of food and cookery science
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• v.20 no.6 s.84
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• pp.589-597
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• 2004

This study was conducted to investigate the effects of various kinds of electrolyzed and chlorinated waters on the sensory and microbiological qualities of fresh-cut lettuce and to determine the most suitable electrolyzed water for the vegetable dishes, without heat treatment, at institutional foodservices. The sensory evaluation resulted in higher scores on the 1st-day of storage for the EW-1 (diaphragm type 1) and EW-3 (non-diaphragm type) compared to that for EW-2 (diaphragm type 2), with regard to their appearance, discoloration, texture, taste and overall acceptability characteristics. However, over time, EW-3 ranked highest, with a score of 8.00 (very like), on the 4th-day of storage, which maintained the highest level up to the 7th-day of storage, at which time the score was 7.00 (fairly like). The CW (chlorinated Water) had a significantly lower score, due to the smell of chlorine, although there was no concern with relation to chlorine residue from the electrolyzed waters. Microbial examinations of the total plate count revealed that immersing lettuce into EW-3 brought about l/3,000 to 1/30,000 reductions in the microbial counts of the TW treatment or untreated samples for up to seven days of storage. The CW treatment gave a 1/10 reduction in the microbial counts compared with the TW (tap water) treatment. The coliform bacterial counts also showed similar trends to those of the total plate count values. With regards to the psychotropic bacterial count, EW-3 was able to result in as much as a 1/30,000 reduction in the initial counts. As vegetable dishes, such as salad, can not be heat-sterilized, the utilization of EW-3 for the preparation of vegetable dishes without heat treatment will be an excellent choice to improve the critical control point in production state as a new effective means for sanitizing management.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.1
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• pp.51-58
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• 2008

Four ruminally cannulated Nili-ravi buffalo bulls were used in a $4{\times}4$ Latin Square design to determine the influence of varying levels of ruminally degradable protein (RDP) on ruminal characteristics, digestibility, blood pH, blood urea nitrogen (BUN) and nitrogen (N) balance. Four isonitrogenous and isocaloric diets were formulated (NRC, 2001). The control diet contained 50% RDP. The medium (MRDP), high (HRDP) and very high (VHRDP) ruminally degradable protein diets had 66, 82 and 100% RDP, respectively. Increasing the level of dietary RDP resulted in a linear decrease in ruminal pH. A quadratic effect of RDP on ruminal pH was also observed with quadratic maxima at the 66% RDP diet. Dietary RDP had a quadratic effect on total bacterial and protozoal count with maximum microbial count at the 82% RDP diet. Increased microbial count was due to increasing level of ruminal ammonia nitrogen ($NH_3-N$). Increasing dietary RDP resulted in a linear increase in dry matter digestibility. Provision of an adequate amount of RDP caused optimum microbial activity, which resulted in improvement in DM digestibility. Increasing the level of dietary RDP resulted in a linear decrease in crude protein (CP) and neutral detergent fiber digestibility. Blood pH remained unaltered across all diets. A linear increase in ruminal $NH_3-N$ and BUN was noted with increasing level of dietary RDP. The increase in BUN was due to increased ruminal $NH_3-N$ concentrations. A positive N balance was noted across all diets. The results are interpreted to suggest that buffalo bulls can utilize up to 82% RDP of total CP (16%) with optimum results.

• Food Science of Animal Resources
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• v.34 no.6
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• pp.792-798
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• 2014

The distribution channel of meat by-products from the pig farm to the final consumer can include a meat processor, wholesale market, wholesaler, retailer, and butcher shop. Bacterial contamination at any of these steps remains to be a serious public health concern. The aim of this study was to evaluate the distribution channel and microbial characteristics of pig by-products in Korea. Upon evaluation of pig by-products in cold storage, we found that the small and large intestine were significantly (p<0.05) higher in pH value compared to the heart and liver. The total plate counts were not significantly different among offals until cold storage for 7 d. The coliform count after 1 d of cold storage was significantly (p<0.05) higher in small and large intestine than in the other organs. The coliform count of heart, liver, and stomach showed a higher coliform count than small and large intestine until 7 d of cold storage. As determined by 16S rRNA sequencing, contamination of major pig by-products with Escherichia coli, Shigella spp., and other bacterial species occurred. Therefore, our results suggest that a more careful washing process is needed to maintain quality and hygiene and to ensure the safety of pig by-products, especially for small and large intestine.