• Korean Journal of Food Science and Technology
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• v.48 no.6
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• pp.536-541
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• 2016

The purpose of this study was to evaluate changes in the quality characteristics of mackerel fish fillet under freezing storage conditions. The changes in product quality were determined by measuring pH, volatile basic nitrogen (VBN); thiobarbituric acid (TBA), lightness ($L^*$), redness ($a^*$), yellowness ($b^*$) values, shearing force, and microbiological evaluation (Total Plate Count, TPC) during 21 days of storage at -20, -5, and $-1^{\circ}C$, and their shelf-lives were established. TPC as an effective quality indicator was used to estimate the shelf-life via linear regression analysis. The TPC increased steadily with increasing storage periods at every temperature (p<0.05) and showed a significant relationship with temperature at $-1^{\circ}C$ (r=0.949), $-5^{\circ}C$ (r=0.919), and $-20^{\circ}C$ (r=0.905). Therefore, based on TPC, the shelf life of the mackerel fillet was noted to be 32 days when stored at $-1^{\circ}C$, more than 51 days when stored at $-5^{\circ}C$, and about 2 months when stored at $-20^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.26 no.3
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• pp.246-249
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• 1994

Shelf-life of pork packaged under $CO_{2}$ was observed and the optimal volume of $CO_{2}$ gas was determined. High gas barrier film, EVOH($CO_{2}$ permiability; 1 $cc/cm^{2}{\cdot}24\;h{\cdot}atm$) was used as packaging material and the volume ratios of sample to $CO_{2}$ of 1 : 1, 1 : 3 and 1 : 5 were tried using the control of vacuum packaged pork. To ev.3luate quality of pork cuts, total plate counts, TBA, color and sensory score were monitored during the storage at $4{\pm}1^{\circ}C$ for 31 days. TPC of vacuum packaged pork increased up to $4.6{\times}10^{6}\;CFU/cm^{2}$ in 24 days while that of $CO_{2}$ gas packaged pork $4.5{\times}10^{5}\;CFU/cm^{2}$ at the same storage period, and it took 7 days more for gas packaged pork to reach the same TPC count. There was no significant difference in TBA value between vacuum packaged and gas packaged pork. In the color L and a values were not affected by treatment but vacuum packaged pork cuts showed higher b value than gas packaged pork. According to sensory evaluation, gas packaged pork showed less off flavor, better flavor and freshness than vacuum packaged one (P<0.05).

• Food Science of Animal Resources
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• v.25 no.2
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• pp.121-126
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• 2005

The changes in quality characteristics and shelf-life of vacuum-shrink packaged Bierschinken after stuffing in fibrous casing and stored at 5 and $10^{\circ}C$ were investigated The total aerobic plate count (APC) of Bierschinken was initially <2.00 $log_{10}CFU/cm^2$, however increased gradually over storage period The APCs of Bierschinken maintained at the level of 4.86 and 5.13 $log_{10}CFU/cm^2$ after 35 days at 5 and $10^{\circ}C$, respectively. pH tended to decrease with the extension of storage period The values of TBA and VBN tended to increase with storage time, of which trend was pronounced at $10^{\circ}C$ rather than at $5^{\circ}C$. According to the sensory evaluation, Bierschinken had the marketing value till 28 days irrespective of storage temperature. The shelf-life of Bierschinken tested might be preferentially restricted by the occurrence of off-odor and off-flavor at the end of storage period.

• Food Science of Animal Resources
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• v.28 no.2
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• pp.204-210
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• 2008

A total of 70 colonies were isolated from the Korean human milk samples on the BCP plate count agar. These LAB isolates were subcultured in 10% reconstituted skim milk, and two strain thereof were finally selected for their highest acid productions. These strains were identified as Enterococcusfaecium based on 16S rDNA sequencing data, named as Enterococcus faecium KHM-11. Sugar utilization of E. faecium KHM-11 was investigated by API 50CH kit, and 19 different sugars including D-arabinose, L-arabinose, galactose, D-glucose, D-fructose, and D-mannose were utilized. For fermentation profiles, a yogurt inoculated by E. faecium KHM-11 after 15 hour, reached at pH 4.09, titratable acidity at 1.10% and average viable counts $1.30{\times}10^9\;CFU/mL$. Effects of the administration of yogurt 0.5% of piglet diet to piglets were investigated for growth rate, analysis of blood and incidence of diarrhea. 24 heads of piglets were divided into two groups: the experimental and the control of 12 animals each. The average growth rate in the yogurt-fed group was higher for 21.67%, compared with control (p<0.05). There were no differences in the concentrations of blood glucose, cholesterol, albumin and globulin between the two treatments. Incidence of diarrhea was no in pigs fed yogurt as compare to control.

• Journal of the Korean Society of Food Culture
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• v.18 no.4
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• pp.311-319
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• 2003

This study was perfomed to evaluate the shelf-life, physicochemical, sensory evaluation of rice cake and noodle mixed with Bakjakyak(Paeonia japonica) powder at different ratio. Moisture content decreased gently during storage and the decrease was less in Bakjakyak powder-added groups than the control group. The color L value decreased significantly by with increasing the Bakjakyak powder and increased during storage. Color a and b value incresed significantly by addition of Bakjakyak powder. In the total plate count, Bakjakyak powder-added group showed less growth of microorganisms compared to the control group. As a result of the sensory evaluation, rice cake and noodle with Bakjakyak were superior in color, flavor, taste, cohesiveness and overall quality than that of control group. The 3%-added group was most superior in terms of color and the 1% added group gained the highest grade in terms of flavor, taste, overall quality. The results suggested that Bakjakyak was effective in increasing the shelf-life and retarding the staling of rice cake and noodle.

• Korean journal of food and cookery science
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• v.14 no.1
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• pp.21-24
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• 1998

The purpose of this study was to evaluate the microbiological quality of kitchen utensils in institutional foodservices in Seoul. Total plate count of plastic container, knife, wiping clothes and cutting board are 1${\times}$$10^3$-1${\times}$10/sup/5(CFU/100 $cm^2$). There were many coliforms in plastic container (2${\times}$$10^1$CFU/100 $m^2$), knife (2-3${\times}$$10^1$CFU/100 $cm^2$), wiping clothes (4-6${\times}$$10^1$CFU/100 $cm^2$) and cutting board (4-9${\times}$$10^1$CFU/100 $cm^2$). The results of microbiological test of kitchen utensils indicated that the sanitary conditions of plastic container, knife, wiping clothes and cutting board should be improved promptly. Electron microscopic observation showed that there were too many bacteria in plastic containers.

• Korean journal of food and cookery science
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• v.24 no.5
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• pp.691-698
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• 2008

In this study, we assessed the quality characteristics of soybean curds (tofu) prepared with Mesangi (Capsosiphon fulvescens) powder (0, 2, 4, 6%, w/w) were investigated. The yields of the curds containing Mesangi were higher than those of the control, and the yield increased with increasing quantities of Mesangi powder. The most abundant mineral in Mesangi tofu was calcium, followed by magnesium. The Mesangi tofu had a slightly lower pH than the control. The addition of Mesangi powder to curd evidenced a significantly lower L value (lightness) and a value (redness) than was detected in the control (p<0.05). The hardness level was highest in the tofu to which 2% Mesangi powder was added. However, this level decreased with increasing concentrations of Mesangi powder. Although the 4% Mesangi tofu evidenced higher adhesiveness than was detected in the control, we noted no significant differences among the Mesangi-treated curds. The soybean curds added to which 2% Mesangi powder was added had evidenced the highest level of cohesiveness, but the tofu containing 4 and 6% Mesangi powder was significantly reduced as compared with the control and 2% Mesangi tofu. Springiness, gumminess, and brittleness were higher in the 2% Mesangi tofu than in the others (p<0.05). The soybean curds prepared with Mesangi powder evidenced a lower total plate count than the controls during over 12 days of storage.

• Journal of agriculture & life science
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• v.45 no.1
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• pp.89-99
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• 2011

This study was carried out to investigate effect of irradiation doses on quality of vacuum-packed dry-cured ham during storage. Dry-cured pork slices were vacuum-packaged in nylon/ polyethylene bags. Vacuum-packed dry curd pork was stored at $10{^{\circ}C}$ for 12 weeks after irradiation (0 kGy, 2.5 kGy, 5 kGy, 7.5 kGy and 10 kGy) and physicochemical properties of dry curd porks, such as meat color surface, thiobarbituric aicd reactive substances, volatile basic nitrogen, pH, microbial (total plate count, Lactobacillus) and sensory properties (color, flavor, overall acceptability) were investigated. Irradiation treatment decreased a*-value, TPC and Lactobacillus. Irradiation dose significantly (p<0.05) increased irradiation flavor and TBA value. However, irradiation dose decreased redness and sensory color in dry-cured ham. The quality of dry-cured ham was affected by the irradiation dose. The results suggested that dry-cured ham irradiated at 5 kGy dose may show optimum quality characteristics of the products as well as microbial safety.

• Korean Journal of Food Science and Technology
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• v.41 no.4
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• pp.392-398
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• 2009

This study identified risk factors of cross-contamination of foodborne pathogens and established a good agricultural practice (GAP) system for an agricultural products processing center (APC) for perilla leaves. All samples were collected before and after a standard work shift at the APC, while perilla leaves were also collected after each step in the APC. In addition, the workers and their surroundings were sampled by swabbing. The total plate count (TPC) and coliform count in the water samples increased significantly (p<0.05) to 3.36 and 1.73 log CFU/mL after work, respectively. However, no Escherichia coli and Listeria monocytogenes were detected. The bacterial populations of the workers and their surroundings did not differ significantly (p${\geq}$0.05) before and after work. However, Staphylococcus aureus (<1.66 log CFU) was detected at a high rate (13-50%) in the basket, packing table, gloves and cloth. Although perilla leaves passed through the washing steps, the TPC and coliform bacterial populations on the final products were higher (p${\geq}$0.05) than those of unwashed perilla leaves, which indicates that the washing system was not functioning properly. Accordingly, a GAP system with a better washing system should be employed at this facility.

• Journal of Food Hygiene and Safety
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• v.30 no.3
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• pp.249-257
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• 2015

The purposes of this study were to develop a small scale post-harvest facility, and consequently to evaluate the effects of applying the facility along with hygiene education on the level of microbial safety in Korean leeks production. A total of 135 samples were collected at three Korean leeks farms in Yangju, Gyeonggi province. Food safety indicators (Aerobic plate count (APC), coliform count, and Escherichia coli) and foodborne pathogens (E. coli O157:H7, Salmonella spp., Staphylococcus aureus, Listeria monocytogenes, and Bacillus cereus) on/in the samples were assessed. The microbial load measured as APC with harvesting tools such as comb, chopping board, and knife, at the farms where the small scale post-harvest facility had been operated (Farms A and B) was lower than that at another farm having no post-harvest facility (Farm C) by 1.44~2.33 log CFU / $100cm^2$. Moreover, the chopping board from Farm C was observed being contaminated with B. cereus at 6.03 log CFU / $100cm^2$. The coliform counts from the samples increased by 0.57~1.89 log CFU/g after leeks was submerged in ground water for washing. E. coli was recovered from leeks, soil, and the ground water used in the washing process, while no E. coli O157:H7, Salmonella spp., and L. monocytogenes was detected. Our results indicated that the small scale post-harvest facility developed in this study as well as the hygiene education played an important role in enhancing the level of microbial food safety in the leeks production environment. However, a disinfection technique could be needed during the washing step in order to prevent a potential contamination.