• Journal of Food Hygiene and Safety
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• v.12 no.1
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• pp.26-38
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• 1997

The quality changes of hams and sausages in refrigerated storage were investigated. Seven types of hams and six types of sausages produced in Korea were collected from markets and stored at 1$0^{\circ}C$ according to the Food Code of Korea, and then chemical, microbiological, textural and sensory characteristics were evaluated at 30, 40 and 50 days. The proximal analysis showed considerable variation in fat with less variation in moisture and protein. The pH values of hams and sausages slightly changed with no consistent difference. Water activity values of all samples except one type of sausage were consistent over time in refrigerated storage. No purge losses of hams were observed except two types of samples in the intial stage. Several types of sausages showed purge losses with no consistency and one type of sausage showed consistent purge losses (0.44~11.29%) during the storage. The volatile basic nitrogen (VBN) content of hams and sausages was still within 20 mg% (Standard and Specification of Korea) on the 50th day, although the VBN of all samples significantly increased over time (p<0.05). The thiobarbituric acid (TBA) values of hams and sausages were well below 1.0 during the storage, although the TBA values of all samples significantly increased (p<0.05). However it was noticed that one type of ham and two types of sausages showed TBA values of 0.945, 0.928 and 0.978, respectively. All the standard plate counts (SPCs) of hams during the storage period showed a level below 30 CFU/g except one type of sample with 103 CFU/g at 50 days. All the SPCs of sausages showed a level below 50 CFU/g except one type of sample with 102 CFU/g and two types of samples with 104 CFU/g on the 50th day. Coliform groups were not counted in all samples during the storage. Instrumental texture analysis showed that springiness, cohesiveness, chewiness, gumminess and adhesiveness slightly changed with no consistent difference. The hardness of the hams showed a decreasing tendency, and the hardness of the sausages an increasing tendency with no significant difference. Sensory evaluation for color, flavor, taste, texture and overall acceptability showed decreasing tendencies over time (p<0.05). The scores of the five sensory characteristics maintained the medium level of quality at the termination of the experiment. Although the results indicated that the ham and sausage samples were acceptable after the 50 days' storage at 1$0^{\circ}C$, the shelf-life of the samples should be determined considering the rapid growth of bacteria and the high TBA values at 50 days.

• Korean Journal of Food Science and Technology
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• v.35 no.6
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• pp.1174-1181
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• 2003

A part of Aspergillus oryzae koji was replaced with Bacillus sp. koji to improve the quality of kochujang, and the resulting effects on enzyme activities, microbial characteristics, and physicochemical properties were investigated during fermentation. The activity of amylase was higher in the kochujang prepared with Asp. oryzae koji. The activity of protease increased as the ratio of Bacillus. sp. koji increased. Viable cell counts of yeast and bacteria of the kochujang increased with increasing ratio of Bacillus sp. koji. The Hunter a-values of the Bacillus sp. koji kochujang were higher, and the degree of increase in the total color difference $({\Delta}\;E)$ was lower in the Bacillus sp. koji group. Consistency and water activity of the kochujang prepared with Bacillus sp. koji was higher, and the pH and titratable acidity of the kochujang also changed slightly. As the ratio of Asp. oryzae koji increased, sugar content decreased. However, the ethanol content of the kochujang did not significantly change. Amino nitrogen content of the kochujang increased, while ammonia nitrogen content decreased as the ratio of Bacillus sp. koji increased. After 12 weeks of fermentation, the result of sensory evaluation showed that C kochujang (75% of Asp. oryzae koji replaced by Bacillus sp.) was more acceptable (p<0.05) than the other groups in taste, color, flavor, and overall acceptability.

• Journal of fish pathology
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• v.22 no.3
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• pp.253-262
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• 2009

We conducted bacteriological and histopathological analysis for olive flounder Paralichthys olivaceus after experimental infection with Streptococcus parauberis (FP2284) isolated from diseased olive flounder under different stress conditions. Experimental challenge was performed in healthy flounder (40.4 g in average body weight) by intraperitoneal (i.p.) injection with $2{\times}10^{8}$ CFU/fish under normal (no stress) or netting (for 2 min, twice/day) stress condition. The cumulative mortalities of no-stress and netting stress group were 70% and 95%, respectively. The most prevalent changes observed in experimentally infected flounder were darkness of skin and inflammation of the heart. Severe pericarditis, myocarditis and fibrosis were observed in the heart of the affected flounder. The results of viable counts showed the number of bacteria of the heart tissue was maintained over the $10^{4}$ CFU $g^{-1}$ heart for 3 weeks after inoculation. Histological lesions of the heart was more extensive and gradual decrease in bacterial numbers of heart tissue was delayed under stress condition.

• Korean journal of food and cookery science
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• v.21 no.4 s.88
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• pp.545-555
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• 2005

The physicochemical and microbial characteristics of Oiji prepared with dry salting method, which has been used industrially for industry, were investigated. Low salting and low storage temperature were employed:extremely low salting extremely low temperature; ESET $(5\%,\;0^{\circ}C)$, very low salting extremely low temperature;VSET $(10\%,\;0^{\circ}C)$, extremely low salting very low temperature; ESVT$(5\%,\;5^{\circ}C)$, low salting very low temperature; VSVT$(10\%,\;5^{\circ}C)$ and high salting low temperature;HSLT$(30\%,\;10^{\circ}C)$ for control. Acidity was lower, and pH was higher in VSET, in of which the fermentation pattern was similar with that of HSLT The time required to reach the optimum acidity ($0.3\%$ lactic acid) was longer delayed for VSET (168 days), than for compared to ESVT (51 days). During storage of Oiji, greenness (-a) as measured with of the Hunter color system wasshowed the highest in VSET, and the lowest while in ESVT, the lowest. Total microbial and lactic acid bacteria counts number were the lowest in HSLT and VSET and were the lowest than in other groups, while the highest in ESVT. Yeast was not detected in HSLT, but was the highest while in VSVT. E coli coliform and listeria were detected in the $5\%$ salting groups, although Salmonella was not detected in any of the all groups. Texture profile analysis demonstrated exhibited that fracturability and hardness were highest in HSLT and VSET, compared to the other groups. Scores of over-all preference for ESVT and HSLT were higher atwith 6.3 and 6.2, respectively, compared to the other products. Based on these results, lower saltiness less than $10\%$ and lower storage temperature (less than $5^{\circ}C$) condition was optimum for maximizing the better for good quality of industrial Oiji preparation in industry.

• Korean journal of food and cookery science
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• v.14 no.4
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• pp.421-429
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• 1998

The effect of glutinous rice paste on the physicochemical, microbiological, and sensory characteristics of Puchukimchi during fermentation was investigated. Puchukimchi is a kind of korean kimchi made with Leek (Allium odorum L.). Puchukimchi made with various concentrations (0.0, 0.5, 1.0, 2.0, 3.0%) of glutinous rice paste were fermentated at 10$^{\circ}C$ up to 45 days. As a fermentation progressed, pH decreased in all of the treatments, while total acidity increased. By increasing the concentrtion of glutinous rice paste added, an increase of total acidity was noted from Puchukimchi. The reducing sugar content in most samples was decreased during fermentation, however, 1.0% treatment showed a relatively slow decrease. The total vitamin C content increased sharply at the 2nd-day of fermentation and then, gradually decreased especially from the 8th-day following a sigmoidal changing pattern. The total vitamin C content was the highest in Puchukimchi made with 1.0% glutinous rice paste. The counts of lactic acid bacteria increased remarkably and then decreased gradually after optimum ripening period, i.e., the palatable period of Puchukimchi during fermentation.

• Korean journal of food and cookery science
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• v.28 no.5
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• pp.515-530
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• 2012

This research aims to audit foodservice sanitation management practices and to assess microbiological quality of foods and their food contact environments in kindergartens. Sanitation auditing was conducted in 10 kindergartens in Seoul, Gyeonggi, and Incheon areas to assess the levels of safety practices. Results revealed that the surveyed kindergartens scored 41.4 out of 100 points, on average. The average scores of each category were 6.4/11 (58.1%) for facilities sanitation, 4.2/12 (35.0%) for equipment sanitation, 2.4/10 (24.0%) for personal hygiene, 5.1/10 (51.0%) for food ingredients management, 6.0/17 (35.3%) for production process, 5.4/10 (54.0%) for environmental sanitation, 2.0/6 (33.3%) for kitchen utensils sanitation, and 2.2/6 (96.7%) for safety management. Microbiological quality of raw, prepared foods, personal sanitation (hands), environmental sanitation, and drinking water were assessed. Total plate counts (TPC) of the following menus exceeded the critical limit: seasoned leek (5 log CFU/g), cucumber (5.0 log CFU/g), panbroiled fish paste (TNTC at $10^4$), tangpyeongchae (5.3 log CFU/g), egg rolls (6.1 log CFU/g), panbroiled sausage (TNTC at $10^4$), and soft tofu pot stew (TNTC at $10^4$). Coliform which exceeded the standard limit were detected from seasoned leek (2 log CFU/g), cucumber (2.5 log CFU/g), panbroiled fish paste (2.0 log CFU/g), egg roll (3.8 log CFU/g), tangpyeongchae (4.0 log CFU/g), panbroiled sausage (2.3 log CFU/g), and soft tofu pot stew (3.7 log CFU/g). For seasoned foods (muchim), S. aureus ranged 2.2~2.9 log CFU/g. In food workers' hands, microbial profiles ranged 3.8~7.9 log CFU/hand for TPC, ND~4.5 log CFU/hand for coliforms, ND~4.7 log CFU/hand for S. aureus, and ND~5.3 log CFU/hand for Enterobacteriaceae. Microbiological profiles of food contact surface of knives, cutting boards, dish-clothes, and trays showed possibilities of cross-contamination. General bacteria were 2.1~4.5 logCFU/ml in 4 purified water samples and E. coli were found in the kitchen of one kindergarten. These results suggested that environmental sanitation management practices need more strict improvement: effective sanitation education methods and practices were strongly required, and more strict sanitation management for cooking utensils and equipment were required.

• Food Science of Animal Resources
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• v.26 no.1
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• pp.127-135
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• 2006

This experiment was carried out to examine the fermentation properties of yogurt with bovine milk and soybean milk at the mixed ratio of 2:1 and added 0.1, 0.2, 0.4 and 1.0% red ginseng extract. The effect on promoting the fermentation by additives 0.1, 0.2, 0.4 and 1.0% red ginseng extracts were higher and pH was $3.90{\sim}3.94$ when Lactobacillus acidophilus KCTC3150 and Lactobacillus salivarius ssp. salivarius CNU27 were used. Titratable acidity showed a little inhibiting due to increasing red ginseng extract content. The average viable counts of lactic acid bacteria after 15 hour culture was the highest level of $6.26{\times}10^8cfu/mL$ when Lactobacillus acidophilus KCTC3150 was used, and the additives content of red ginseng extract was 1.0% The production of lactic acid was the highest and the concentration was 332.22 mM when Lactobacillus acidophilus KCTC3150 was used, and the additives content of red ginseng extracts was 1.0% Lactose hydrolysis was completely hydrolyzed when Lactobacillus acidophilus KCTC3150 and Lactobacillus salivarius ssp. salivarius CNU27 were used. The highest viscosity of yogurt was 780 cP when Lactobacillus acidophilus KCTC3150 and Lactobacillus salivarius subsp. salivarius CNU27 were used and red ginseng extract was added 1.0% The overall acceptability, $4.17{\pm}0.64$, was the highest when Lactobacillus salivarius subsp. salivarius CNU27 was used and the additives content of red ginseng extract was 0.2%.

• Korean journal of food and cookery science
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• v.25 no.1
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• pp.8-15
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• 2009

This study was carried out to examine changes in the quality characteristics of Aralia continentalis Kitagawa (AcK) Jangachi made with different $CaCl_2$ and seasoning treatments during storage at $4^{\circ}C$ for 6 months. The results exhibited there were no significant changes in pH, acidity, and salinity in the various samples. The numbers of total bacterial counts and lactic acid bacteria increased slowly during the early storage period and then increased rapidly in the third month. In the fifth month they reached their highest level near $6.6{\times}10^{6}cfu/ml$ and then decreased thereafter. The sample treated with $CaCl_2$ exhibited a higher degree of hardness than the untreated sample. Finally, the sensory characteristics of the AcK Jangachi were highly acceptable during the entire storage period in terms of color, smell, bitterness, texture, and general preference regardless of the $CaCl_2$ treatments.

• Korean journal of food and cookery science
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• v.32 no.6
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• pp.716-723
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• 2016

Purpose: This study was conducted to improve the quality characteristics of pork intestine through different pretreatment processes. Methods: We washed pork intestine by both physical (tap water, UV, and sonication) and chemical methods (alcohol, acetic acid, flour and NaCl) as pretreatment process. The physicochemical (pH, color, volatile basic nitrogen (VBN), and 2-thiobarbituric acid reactive substances (TBARS)) and microbial properties of pre-treated pork small intestine were evaluated. Results: The nature of the pretreatment method influenced the pH value of pork small intestine. The acetic acid treatment resulted in the lowest pH value. In physical method, the color value and the number of microorganism were significantly affected by sonication as compared to other treatments. TBARS value of pork small intestine after all the treatments was lower than the control. However, VBN exhibited no significant differences in its value irrespective of the nature of treatment. Appearance and control exhibited lowest value in response to sonication treatment. However, off-flavor and overall acceptability were higher in sonication treatment than other treatments. In chemical method involving NaCl and flour treatments, lightness and redness were lower than other treatments. Lowest VBN and TBARS values were noted in alcohol and acetic acid treatmentsand no growth of E. coli and coliform bacteria was observed. The other treatments resulted in lower values of VBN, TBARS, and microbial counts than the control. Appearance and color value after alcohol, acetic acid, and flour treatment were lower than the control and NaCl treatment. Off-flavor and overall acceptability of by-product after alcohol, flour, and NaCl treatments were higher than the control and acetic acid treatment. Conclusion: Overall, we present NaCl treatment and sonication treatment in the form of a combination pretreatment method as the optimal condition for processing pork intestine.

• Applied Biological Chemistry
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• v.46 no.3
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• pp.229-234
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• 2003

The traditional kochujang supplemented with mushrooms (Pleurotus ostreatus and Lentinus edodes) was prepared, and changes in quality characteristics during fermentation at ambient temperature were investigated. The moisture content of kochujang increased by addition of mushroom. The titratable acidity of mushroom-added kochujang was gradually increased during fermentation. Ethanol contents of mushroom-added kochujang decreased with the addition of oyster mushroom, but increased with the addition of oak mushroom. The amino-nitrogen contents increased gradually during fermentation, resulting in significantly higher contents of 9% mushroom-added kochujang than others. The a value of kochujang decreased greatly during fermentation, but L, a and b values showed significantly higher than the control. The growth of bacteria in kochujang was delayed by the addition of mushrooms. Bacterial and yeast counts at the end of fermentation were not influenced by the addition of mushrooms. Sensory evaluation test revealed that color and flavour of kochujang were improved by the addition of mushrooms, and higher score was obtained from the addition of oyster mushroom compared to oak mushroom.