• Korean journal of food and cookery science
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• v.19 no.2
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• pp.188-194
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• 2003

This study was conducted to investigate the effect of beef bone extracts on the organoleptic quality and fermentation of Baeck Kimchi. For this study, the organoleptic characteristics of Baeck Kimchi, with addition beef bone extracts were tested, and the changes in the fermentation factors, such as pH, acidity, reducing sugar and total microbial count, were observed during fermentation at 10$^{\circ}C$ and 20$^{\circ}C$. Greater amounts of lipids and soluble nitrogen were extracted to increasing the boiling time for the preparation of the beef bone extracts. However, 1% of the mixed beef bone extracts, prepared by boiling for 5, 7 and 9 hours, was the most acceptable for the Baeck Kimchi fermentation, as assessed from the results of sensory consumer tests. The beef bone extracts enhanced the umami taste of the unfermented Baeck Kimchi. The carbonated taste, sourness and fresh flavor of the fermented Baeck Kimchi were also enhanced. The fermentation rate was increased by the addition of beef bone extracts to Baeck Kimchi.

• Journal of Food Hygiene and Safety
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• v.27 no.3
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• pp.277-284
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• 2012

The objective of this study was to investigate and evaluate microbial contamination levels of leafy greens (perilla leaf and lettuce) and its distributing conditions at different seasons (Feb, May, Aug, and Nov of the year 2011) in order to provide insight into any potential health hazards associated with consumption of these commodities. Leafy greens were collected from a farm located in Geumsan, Chungnam and wholesale markets (WM) and traditional markets (TM) located in Suwon. At the same time, temperature and relative humidity fluctuations experienced by the leafy greens during distribution from the farm to the distribution center were measured by a data logger. The contamination levels of perilla leaf and lettuce were determined by analyzing total plate count. Coliform groups, Bacillus cereus, Escherichia coli, Escherichia coli O157:H7, Salmonella spp., Listeria monocytogenes and Staphylococcus aureus were determined. The contamination levels of total aerobic bacteria, coliform groups and B. cereus in both vegetables sampled during May and August found to be higher than those sampled during February and November. E. coli O157:H7, Salmonella spp., L. monocytogenes were not detected in the vegetables analyzed in this study. There were no significant trends between samples at WM and TM in the contamination levels. Relative humidity of vegetables distributed from the farm to the distribution center showed over 90% during distribution regardless of measured seasons. In the case of background microflora on leafy greens, the density was significantly increased at 20, 30 and $37^{\circ}C$ during storage of 24h. E. coli O157:H7 and B. cereus inoculated on the leaves also showed similar increases in the storage tests. The microbial contamination levels determined in this study may be used as the fundamental data for microbial risk assessment.

• Food Science and Preservation
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• v.16 no.6
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• pp.965-970
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• 2009

PCR technology has been widely used to detect and quantify microbial pathogens in foodstuffs, because the technique is rapid, sensitive, and selective. In this study, detection of contaminating pathogenic bacteria on shells of chicken eggs was performed using both a commercial multiplex polymerase chain reaction (PCR) kit and a viable count method employing a selective medium. The PCR kit was capable of detecting Campylobacter jejuni, Escherichia coli O157:H7, Staphylococcus aureus, Bacillus cereus, Vibrio parahaemolyticus, Listeria monocytogenes, Yersinia enterocolitica, Salmonella species, and Shigella species. Using the PCR method, five bacterial species were detected from 30 samples (33.3%) of 90 batches of eggs commercially available in a market. PCR products from B. cereus, S. aureus, L. monocytogenes, Y. enterocolitica, and E. coli O157:H7 were detected, and the numbers and frequencies of positive samples were 17 (18.8%), 12 (13.3%), 15 (16.6%), 16 (17.7%),and 4 (4.4%), respectively. None of any Salmonella species, C. jejuni, V. parahaemolyticus, or Shigella species was detected in this study. The results of PCR testing were confirmed using a typical viable count method employing a selective medium. We suggest that the multiplex polymerase chain reaction (mPCR) assay is a rapid and reliable method for detection of pathogenic bacteria contaminating eggs.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.9
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• pp.1285-1291
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• 2017

Objective: A trial was conducted from 11 to 42 d post-hatch to investigate the effectiveness of the supplementation of a multiple-enzyme preparation (Natuzyme Plus) in a wheat-based diet on digesta viscosity, pH and microbial population, villus morphology, feed passage time, nutrient retention, carcass characteristics, blood lipid parameters and growth performance of broiler chickens. Methods: Three hundreds 10-d-old male Ross 308 chicks were allocated to three diets with five replicates of 20 birds per replicate. Dietary treatments were i) a wheat-based diet (W), ii) W+Natuzyme Plus (WN; 500 mg/kg of the diet), and iii) a corn-based diet (C). Results: Birds fed on the C diet had higher average daily gain (ADG, p<0.01), villus height (VH, p<0.01), total tract apparent retention (TTAR) of nitrogen (NT, p<0.01) and ether extract (EE, p<0.01), nitrogen-corrected apparent metabolizable energy ($AME_n$, p<0.05), relative weight (RW, % of body weight) of carcass (p<0.05), blood concentration of triglyceride (TG, on d 40 [p<0.01]), total cholesterol (TC, on d 22 [p<0.05]) and low density lipoprotein (LDL, on d 22 [p<0.01] and 40 [p<0.05]), and also lower feed conversion ratio (FCR, p<0.01), digesta viscosity (p<0.01), count of coliforms (p<0.01) and Escherichia coli (p<0.01) and epithelium thickness (ET, p<0.05) than those fed on the W diet. ADG, FCR, VH, ET, TTAR of NT and EE, RW of carcass, blood concentration of TG (on d 40), TC (on d 22) and LDL (on d 22 and 40) values of the WN diet did not show a significant (p>0.05) difference compared to those of the C diet. Compared to those of the W diet, the WN diet showed the higher count of Lactobacilli and lower count of coliforms (p<0.01) and digesta viscosity (p<0.01). Conclusion: In general, the results of this study showed that Natuzyme Plus supplementation in a wheat-based diet can be appropriate to achieve a comparable growth performance in broiler chickens to those given the C diet probably through improving digesta viscosity, VH, ET, TTAR of NT and EE, $AME_n$, count of Lactobacilli and coliforms.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.9
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• pp.1340-1349
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• 2017

Objective: This study aimed to evaluate the microbiological and cellular milk profile for the diagnosis of subclinical mastitis in female buffaloes and to assess risk factors for predisposition of the disease. Methods: Analyses were carried out by standard plate count (SPC), identification of species and antibiotic resistance, somatic cell count (SCC), electrical electrical conductivity of milk (ECM), and lactoferrin content in milk. Teat cups were swabbed to evaluate risk factors, observing hyperkeratosis, milking vacuum pressure and cleanliness of the site. Hence, 30 female buffaloes were randomly selected (15 from a group in early lactation and 15 in late lactation). Results: The most common bacteria in the microbiological examination were Staphylococcus spp., Streptococcus spp. and Corynebacterium sp. In the antibiotic sensitivity test, 10 (58.82%) of the 17 antibiotics tested were sensitive to all isolates, and resistant bacteria were Streptococcus uberis, Streptococcus dysgalactiae, Streptococcus haemolyticus, and Escherichia coli. It was observed that positive samples in the microbiological examination showed total bacterial count between $9.10{\times}10^3$ to $6.94{\times}10^6$ colony forming units/mL, SCC between 42,000 to 4,320,000 cells/mL and ECM ranging from 1.85 to 7.40 mS/cm. It was also found that the teat cups had high microbial counts indicating poor hygiene, and even faults in the cleanliness of the animals' waiting room were observed. It is concluded that values of SCC above 537,000 cells/mL and ECM above 3.0 mS/mL are indications of mammary gland infection for this herd; however, the association of these values with a microbiological analysis is necessary to more accurately evaluate the health status of mammary glands with subclinical mastitis. Conclusion: Through phenotypic characterization of bacteria involved in the samples, the genera Staphylococcus spp., Streptococcus spp., and Corynebacterimum bovis were the most prevalent in this study. Faults in environment and equipment hygienization are factors that are directly associated with mastitis.

• Journal of Food Hygiene and Safety
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• v.35 no.2
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• pp.170-176
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• 2020

We investigated the pH, volatile basic nitrogen (VBN), microbial changes and dominant microbes in raw beef, wet-aging beef, and dry-aging beef after the meat had been stored in a refrigerator. The count of mesophilic bacteria was 3.3-3.9 log CFU/g in raw beef and dry-aging beef, and 5.4 log CFU/g in wet-aging meat. After 18 days of refrigeration, the mesophilic bacterial count in raw and aging beef increased to 6.1-6.4 log CFU/g. In wet-aging beef, the number of lactic acid bacteria increased from 4.5 log CFU/g to 6.0 log CFU/g at refrigeration temperature. However, lactic acid bacteria were not detected in dry aging beef. Major foodborne pathogens such as Salmonella spp, Listeria monocytogenes, and Escherichia coli (EHEC) were not detected. Based on the legal standard for mesophilic bacteria count, the estimated shelf-life of aged beef was less than 12 days and the average VBN was 15 mg%. The dominant microorganisms varied between the different types of meat. In raw meat, Staphylococcus saprophyticus was the dominant microorganism, and as the VBN increased, Carnobacterium divergens dominated. In wet-aging beef, Carnobacterium divergens dominated during the initial days of refrigeration after which the number of Lactobacillus sakei increased. Dermacoccus nishinomiyaensis was initially the dominant microbe in dry-aging beef, after which Pseudomonas fragi dominated. In addition to the role of specific bacteria in the early stage of decay, it is thought that microorganisms can be utilized for safe distribution and storage of matured meats by conducting research on changes in rot, fragrance analysis, and changes of ingredients in matured meats.

• The Korean Journal of Food And Nutrition
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• v.26 no.4
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• pp.678-684
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• 2013

This study measured the change of lactic acid bacteria during the ripening fermentation process of low salt fermented squid with no squid ink added. All study groups showed increase of Leuconostoc and rapid growth of total plate count at the beginning stage of ripening and the maximum microbial count showed at the optimum stage of ripening which gradually reduced after the optimum stage. It is believed that Lactobacillus occupied the major part of the total plate count after the optimum stage of the squid fermentation, and it was related to the quality after the optimized ripening stage. Streptococcus and Pediococcus were gradually increased until the optimum stage of the ripening, and then decreased rapidly. Yeasts were detected in the middle stage of the fermentation and rapid increase was shown after the last stage of the fermentation which suggests that yeasts participate in putrefaction of the low salt fermented squid. The change of lactic acid bacteria observed during the ripening fermentation of low salt fermented squid with squid ink added was that the total plate count increased until ripening middle stage but showed a tendency to slightly reduce after the middle stage. The length of time to reach the maximum value was longer than the no treatment groups. Among the lactic acid bacteria, Leuconostoc, Streptococcus and Pediococcus has increased until the middle stage of the ripening while Lactobacillus constantly increased to the end part of the ripening. Yeasts had no increasing in the early ripening stage, but after middle of the ripening, it started to increase. That kind of tendency was similar to the case of no treatment groups. However, the amount of lactic acid bacteria tended to be less than no treatment groups. The tendency of decreasing number of all bacteria in low salt fermented squid with squid ink added shows squid ink restricts the growth of all bacteria.

• Korean Journal of Microbiology
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• v.44 no.1
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• pp.43-48
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• 2008

Standard sample for quality control of total coliform measurement was procured by addition of nalidixic acid and cephalexin as bacteriostatic agents to Escherichia coli cultured broth. After making the standard sample, the number of E. coli was measured by fluorescence microscopic count method and plate count method by 12 hr interval. The numbers of E. coli remained unchanged for at least for 48 hr at room temperature which ranged from 3.5 to $4.2{\times}10^5\;cells/ml$ and from 1.0 to $1.2{\times}10^4\;CFU/ml$ by direct fluorescence microscopic count method and plate count method, respectively. This result suggests that microbial standard sample with bacteriostatic agents of nalidixic acid and cephalexin is usable for quantitative quality control.

• Journal of the Korean Society of Food Culture
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• v.16 no.5
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• pp.431-441
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• 2001

To develop the low-temperature and long-term fermented kimchi, kimchi was prepared according to the recipe of a specific ratio of major and minor ingredients and adjusted its salinity to 3.7%. Prepared kimchi fermented at $15{\pm}1^{\circ}C$ for 24 hours and transferred and fermented in a refrigerator only used to make low-temperature and long-term fermented kimchi at $-1{\pm}1^{\circ}C$ for 30 weeks. During 30 weeks of fermentation the changes in physicochemical and microbiological properties of low-temperature and long-term fermented kimchi were studied. The initial pH of 6.47 decrease gradually and dropped to pH 4.0 after 14 weeks of fermentation, and then it maintained at same level. Acidity increased to 0.49% on 2 weeks of fermentation and kept at 0.47 $\sim$0.50% during 2 to 30 weeks fermentation. Salinity was slightly increased at early stage and started to decrease on 4 weeks of fermentation, and then it did not change. The change of reducing sugar content was closely related to the trend of pH change with a very high correlation coefficient(r =0.912). Lactic acid, citric acid, malic acid, succinic acid and acetic acid were major organic acids contained in low-temperature and long-term fermented kimchi. Vitamin C content decreased at initial stage of fermentation and then slightly increased up to the maximum of 22.3 mg% on 8weeks of fermentation. In color measurement, L value continued to increase during the fermentation and reached at the highest of 55.45 on 22 weeks of fermentation, and a and b values of 3.62 and 4.54 also increased to 31.26 and 37.32 on 30 weeks of fermentation, respectively. Total microbial count increased slowly from beginning and was the highest on 4 weeks of fermentation, and then began to decrease slowly. Count of Lactobacillus spp. was highest after 6weeks, but count of Lactobacillus spp. was highest on 2 weeks of fermentation, and then both showed a slow decrease. Yeast count wasn't increased until 4 weeks of fermentation and then increased rapidly to get the highest on 10 weeks of fermentation.

• Food Science and Preservation
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• v.6 no.4
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• pp.417-423
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• 1999

Quality changes of crown daisy and kale were investigated during storage at 10$^{\circ}C$ after washing with cooled electrolyzed acid water at 3 times in 2 min. Total count and coliform count of crown daisy and kale after immersion in electrolyzed acid water were decreased to 1/130 and 1/1,170 of non-immersed crown daisy and to l/870 and l/470 of non-immersed kale. However total count and coliform count were increased to the similar levels of non-immesed and tap water immersed one after 6 days of storage. Weight loss of crown daisy and ka1e were lower than others for 3 days of storage but higher than that of one after that time. Decay rate of crown daisy and kale immersed electrolyzed acid water showed lower than that of non-immersed and tap water immersed one for 6 days. In case of kale, rupture strength was higher than others at just after immersion and showed similar values after initial storage period. Color value of both crown daisy and kale showed high L, b and low a value in the order of electrolyzed acid water, tap water and non-treatment. Chlorophyll content of crown daisy and kale were lower than those of others just after immersion in electrolyzed acid water, but showed rapid reduction in the order of non-treatment. tap water and electrolyzed acid water after 6 days. Overall organoleptic properties of crown daisy and kale in immersion electrolyzed acid water were higher than those of others.