• Food Science of Animal Resources
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• v.27 no.1
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• pp.127-131
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• 2007

In order to investigate the presence of pathogenic bacteria in fresh pig loin and the growth changes of microorganism in raw ham during storage at 10 and $25^{\circ}C$. These hams were manufactured according to a short-ripening procedure being completed in 4 weeks with dry-curing followed by wet-curing and ripening. The result regarding the contamination level of microorganism in the fresh raw pig loin showed that the count of total aerobes was $3.11\;log\;CFU/cm^2$, and the population of lactic acid bacteria, Pseudomonas spp., Clostridium spp., and yeast and mould had not risen over $2\;log\;CFU/cm^2$ on the storage time. However, the average count ofEnterobacteriaceae in pork loin was $3.11\;log\;CFU/cm^2$, which represented the predominant species. The pathogenic bacteria including Salmonella spp, Staphylococcus aureus, Vibrio parahaemolyticus, Clostridium perfringene, Listeria monocytogenes, and Escherichia coli O157:H7 were not detected either in fresh pork loin or in raw ham products stored at 10 and $25^{\circ}C$. The initial count of total aerobes in raw ham samples was 3.06 log CFU/g, and increased slightly after 90 days at 10 and $25^{\circ}C$ to 4.6 and 4.69 log CFU/g, respectively. The predominant species in raw ham products during storage time were lactic acid bacteria and Staphylococcus spp.

• Food Science of Animal Resources
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• v.18 no.3
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• pp.232-239
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• 1998

This experiment was conducted to investigate radurization effects of gamma ray and electron beam irradiation at 1.5 and 3.0 kGy on beef steaks during 8 days of storage at 5$^{\circ}C$. Total bacteria count, psychrotrophs, mesophiles and thermophiles were analyzed at 2 days intervals. Nonirradiated beef steak was used a scontrol Total bacteria counts, psychrotrophs, mesophiles and thermophiles of the control samples showed 3.03∼4.72 logCFU / g at 0 day and increased to 7.67∼10.90 logCFU / g during 8 days storage except thermophiles. Total bacteria counts, psychrotrophs and mesophiles of beef steaks at 8 days were significantly (p＜0.05) decreased to 3.61∼5.43 logCFU / g by gamma ray and to 3.83∼7.02 logCFU / g by electron beam irradiation at 1.5 and 3.0 kGy. Thermophiles of all irradiated samples at any dose were not detectable through 8 days storage. These results suggested that both gamma ray and electron beam irradiation were effective to extend lag phase of bacterial growth of refrigerated beef. Gamma ray irradiation was better than electron beam irradiation in terms of radurization effects of beef.

• Food Science and Biotechnology
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• v.16 no.6
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• pp.1018-1022
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• 2007

Effect of aqueous chlorine dioxide treatment on the microbial growth and quality changes of strawberries during storage was examined. Strawberries were treated with 5, 10, and 50 ppm of chlorine dioxide solution, and stored at $4{\pm}1^{\circ}C$. Total aerobic bacteria in strawberries treated at 50 ppm of chlorine dioxide were increased from 1.40 to 2.10 log CFU/g after 7 days, while increasing in the control from 2.75 to 4.32 log CFU/g. Yeasts and molds in strawberries treated at 50 ppm of chlorine dioxide were increased from 1.10 to 1.97 log CFU/g after 7 days, while the control was increased from 2.55 to 4.50 log CFU/g. The pH and titratable acidity of strawberries were not significantly different among treatments. Sensory evaluation results showed that chlorine dioxide-treated strawberries had better sensory scores than the control. These results indicate that chlorine dioxide treatment could be useful in improving the microbial safety and qualities of strawberries during storage.

• Korean journal of food and cookery science
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• v.11 no.3
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• pp.261-266
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• 1995

The survival and growth of Staphylococcus aureus and Listeria monocytogenes in fish homogenates (flounder, shrimp and oyster homogenate) and tryptic soy broth (TSB) were tested during storage at simulated ambient (35$^{\circ}C$), refrigerated (5$^{\circ}C$) and frozen (-20$^{\circ}C$) temperature. A similar growth pattern of S. aureus at 35$^{\circ}C$ was observed in fish homogenates and TSB. Survival of S. aureus decreased at refrigerated or frozen temperature and that was greater at -20$^{\circ}C$ (0.3-1.2 log reduction/6 weeks) than at 5$^{\circ}C$ (1-1.6 log reduction/3 weeks). Viable cells of L. monocytogenes increased rapidly at 35$^{\circ}C$ in flounder homogenate, shrimp homogenate and TSB but after a prolonged lag period in oyster homogenate. During 3 weeks of storage at 5$^{\circ}C$, the levels of L. monocytogenes increased 3.8-5.0 log cycles in flounder homogenate, shrimp homogenate and TSB whereas levels increased 2.2 log cycles in oyster homogenate. Viable cells of L. monocytogenes during 6 weeks of frozen storage decreased 1.5-1.8 log cycles in flounder homogenate, shrimp homogenate and TSB while decreased 2.8 log cycles in oyster homogenate.

• Journal of Korean Society of Forest Science
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• v.104 no.4
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• pp.558-563
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• 2015

The effects of pre-treatment methods (water cooling, water cooling+ozone, precooling+microbubble, water cooling+ozone+microbubble) after harvest on the quality of 'Mipung' chestnut were studied. Changes in quality of chestnut were greater precooling treatments effect than washing treatments. But, decaying rate and total microorganism were significantly differences among treatments. The decaying rate after 12 weeks storage was highest at 20.0% in non-treatments and lowest at 3.3% in water cooling+ozone and water cooling+ozone+microbubble treatments. The total microorganism immediately after washing treatments was in the order non-treatments (4.4 log CFU/g) > water cooling treatments (4.0 log CFU/g) > water cooling+ozone+microbubble treatments (3.5 log CFU/g) > water cooling+ozone treatments (3.4 log CFU/g) > water cooling+microbubble treatments (3.3 log CFU/g), and after 12 weeks storage was increased within 4.7 to 5.9 log CFU/g. Thus, the washing treatments, especially ozone treatments, extended the shelf-life of the 'Mipung' chestnut by inhibiting the decaying.

• Applied Biological Chemistry
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• v.50 no.1
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• pp.42-47
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• 2007

Effect of chlorine dioxide ($ClO_2$) treatment on the microbial and physicochemical changes of fish paste was investigated. Fish paste samples were treated with 5, 10, and 50 ppm of $ClO_2$ solution, respectively, After $ClO_2$ treatment, fish paste samples were individually packaged and stored at 4$^{\circ}C$. The initial microbial loads of samples were 3.8 log CFU/g in total bacterial count, and 2.5 log CFU/g in yeasts and molds. Microbial growth of fish paste during storage showed that populations of total bacteria, yeast and mold were significantly reduced by $ClO_2$ treatment. In particular, the treatment of 50 ppm $ClO_2$ decreased total bacterial count the most significantly among the $ClO_2$ treated fish pastes. The pH and VBN of fish paste decreased with increasing $ClO_2$ concentration. Thiobarbituric acid reacted substance (TBARS) values of treated fish paste increased during storage, regardless of $ClO_2$ concentration. This study showed that 50 ppm chloride dioxide was the optimum dose level to extend the shelf-life of fish paste.

• Food Science of Animal Resources
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• v.35 no.5
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• pp.611-614
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• 2015

This study was performed to apply a protein film containing a natural antimicrobial compound to meat packaging and determine quality change of meat during storage. Proteins obtained from the by-products of food processing have been utilized as biodegradable film sources. Porcine meat and bone meal (MBM) is obtained during meat processing, and proteins from the MBM can be extracted and used as a film base material. Previously, an antimicrobial MBM film containing coriander oil (CO) was prepared and its physical properties and antimicrobial activity were characterized. In this study, the antimicrobial MBM-CO film was applied to beef patties packaging, and the microbial population and the degree of lipid oxidation were determined during storage at 4℃ for 15 d. The population of inoculated E. coli O157:H7 in the samples wrapped with the MBM-CO film was 6.78 log colony forming unit (CFU)/g after 15 d of storage, whereas the control had 8.05 Log CFU/g, thus reducing the microbial population by 1.29 Log CFU/g. In addition, retardation of lipid oxidation in the patties was observed during storage for the samples packaged by the MBM-CO film, compared with the control samples. These results suggest that the MBM-CO film can be useful for enhancing the quality of beef patties during storage.

• Food Science and Preservation
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• v.5 no.1
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• pp.89-96
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• 1998

The antibacterial activity of clove (Eugenia caryophyllata Thumb) in culture troth against S. aureus was tested at 35, 5, -20, 50, 55 and 60$^{\circ}C$. Tryptic soy broth(TSB) containing 0∼0.5%(w/v) of clove was inoculated with 105∼107 CFU/ml of S. aureus and incubated at each temperature. The growth of S. aureus occured at 0.1% clove after a prolonged lag period while viable cells of S. aureus decreased more than 2 log cycles at 0.3 and 0.4% clove during 12 hours storage at 35$^{\circ}C$. During 32 days of refrigerated storage at 5$^{\circ}C$, survivors of S. aureus were decreased with the progress of time and increasing clove concentration. At the presence of 0.2, 0.3 and 0.4% clove, bacterial cells were dead after 32, 20 and 16 days of refrigerated storage, respectively. During 32 days of frozen storage at -20$^{\circ}C$, survivors of S. aureus were decreased less than 0.5 log cycle at 0% clove. At the presence of 0.1∼0.4% clove, survivors were decreased 2.5∼3.0 log cycles after 1 day and then decreased 0.4∼0.8 log cycles through the frozen storage. There were small changes in populations of S. aureus in TSB between different concentrations of clove during frozen storage. The D-values of S. aureus at clove 0, 0,2, 0.4% were 28.53, 15.14, 8.9 min at 50$^{\circ}C$, 18.43, 10.32, 6.74 min at 55$^{\circ}C$ and 12.78, 9.88, 5.72 min at 60$^{\circ}C$, respectively. The D-values for S. aureus were decreased with the increasing temperature and clove concentration.

• Journal of Applied Biological Chemistry
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• v.59 no.1
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• pp.69-74
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• 2016

The objective of this study was to examine the combined effect of fumaric acid with mild heat on the inactivation of microorganisms on spinach. Spinach leaves were inoculated with Escherichia coli O157:H7 and Listeria monocytogenes. Based on the results of single treatment of fumaric acid (0.1, 0.3, and 0.5%) or mild heat (40, 50, and $60^{\circ}C$) regarding the inactivation of the inoculated bacteria, the optimal condition for the combined treatment was suggested to be 0.5% fumaric acid and mild heat treatment at $50^{\circ}C$ for 5 min. The combined treatment of fumaric acid with mild heat caused 2.53 and 2.62 log reductions of the populations of L. monocytogenes and E. coli O157:H7, respectively. In addition, during storage of fresh spinach at $4^{\circ}C$ for 12 d, the combined treatment reduced initially the populations of total aerobic bacteria by 2.77 log CFU/g compared with the control. In particular, after 12 d of storage, the population of total aerobic bacteria for the combined treatment sample was 4.84 log CFU/g, whereas the control sample had 6.66 log CFU/g. Color and vitamin C content of spinach samples were not altered significantly by the combined treatment during storage. These results indicate that the combined treatment of fumaric acid with mild heat is an effective method to control microorganisms on spinach during storage.

• 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.