• Food Science of Animal Resources
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• v.30 no.5
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• pp.780-786
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• 2010

This study compared the effects of autoclaving (AC; $121^{\circ}C$ for 15 min), gamma (GR), and electron beam irradiation (EB; 0-20 kGy) on the microbial, physicochemical, and sensory properties of ready-to-eat bulgogi during storage at $35^{\circ}C$ for 90 d. No viable cells were observed (p<0.05) upon AC, GR or EB at more than 15 kGy. However, adverse effects such as tenderization and deterioration of sensory properties were induced in bulgogi upon AC and high dose irradiation. Especially, the hardness and sensory qualities (texture and taste) of the AC-treated samples were extremely deteriorated (p<0.05). These results indicate that use of GR and EB (15 kGy) can ensure the microbial safety of bulgogi without compromising the hardness and sensory properties (texture, taste and flavor).

• Korean Journal of Food Science and Technology
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• v.36 no.5
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• pp.711-716
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• 2004

Gamma irradiation was applied to dried pollack to improve its microbiological quality and evaluate quality stability of irradiated samples. Thermoluminescence (TL) properties of minerals separated from irradiated samples were measured for possible use in identifying irradiation treatment. Dried pollack was packaged in commercial unit (PVC film, 0.06 mm thickness) and stored at $15{\pm}1^{\circ}C$ for 6 months. Samples showed over $10^4\;CFU/g$ in total aerobic bacteria or yeasts&molds, which increased during storage, reaching $10^6-10^7\;CFU/g$ at 3rd month of storage. Irradiation at 3 kGy was effective for improving hygienic quality for 6 months, keeping microbial population under 20 CFU/g. Gamma irradiation at 3 kGy or less did not significantly influence physicochemical quality attributes, such as browning, TBA value, volatile basic nitrogen, trimethylamine, and sensory properties, whereas storage time remarkably induced quality changes of dried pollack. TL analysis was proved suitable for identifying irradiated from non-irradiated samples over 6 months of storage.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.4
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• pp.506-512
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• 2003

Peach wine was fermented at $25^{\circ}C$ for 2 weeks using Saccharomyces cerevisiae KCCM 12224, aged at 15$^{\circ}C$ for 14 weeks, and its physicochemical and microbiological changes were investigated. The viable bacterial cell numbers, 1.4$\times$10$^3$ CFU/mL at the beginning of fermentation, increased to 2.8$\times$10$^{6}$ CFU/mL after 2 weeks, but decreased to 7.0$\times$10$^3$ CFU/mL after 14 weeks. The viable yeast cell numbers were changed from 3.4$\times$10$^2$ CFU/mL to 2.4$\times$10$^{7}$ CFU/mL during fermentation, and decreased to 4.0$\times$10$^4$ CFU/mL after aging. Turbidity total sugar content, reducing sugar content, solid content and b value of peach wine decreased during fermentation but acidity, alcohol content, L and a value increased. Most physicochemical properties except alcohol content and reducing sugar content were not changed significantly during aging. When peach wine was filtered through 0.45 ${\mu}{\textrm}{m}$ nitrocellulose membrane followed by various ultrafiltration membranes with different molecular weight cut-off values, Biomax 100K membrane, with 79 liter/$m^2$/h (LMH) of initial flux, was suitable for ultrafiltration process of peach wine. These membrane filtration treatments resulted in complete removal of microorganisms and decrease in turbidity and alcohol content without changes in other chemical properties. The physicochemical properties of peach wine were not changed and any microorganisms were not found during the storage at 3$0^{\circ}C$ for 12 Weeks.

• Journal of Applied Biological Chemistry
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• v.57 no.4
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• pp.287-294
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• 2014

To improve the shelf life of low-salt Kochujang, Korean hot pepper paste, antimicrobial materials were added at different times before and after aging. The kochujang was then packaged and stored at $30^{\circ}C$ for 15 weeks, and changes in microbiological and physiochemical properties were evaluated. Hunter a- and b-values decreased considerably during storage. The total color difference (${\delta}E$) was greater in the ethanol-chitosan (EC) treatment than in the control and after pasteurization (A-P) treatment. Gas was produced until the seventh week of storage. The control and the A-P treatments produced more gas than the other treatments, and these had the largest number of yeasts and aerobic bacteria. The pH of the EC treatment was higher than that of the other treatments, and the A-P treatment had the highest level of titratable acidity. During storage, the oxidation-reduction potential was lower in the EC and ethanol-mustard-chitosan (EMC) treatments. The reducing sugar content decreased remarkably in the control and A-P treatments, with high production of ethanol. There was a significant change in the content of amino-type nitrogen in the control and A-P treatments, and the content of ammonia-type nitrogen was lowest in the EMC treatment. In the sensory test of kochujang, the ethanol-mustard (EM) and ethanol (E) treatments were significantly higher than the EC, control, and A-P treatments (p <0.05). EM or E alone was effective in extending the shelf life of kochujang when added before aging.

• Fisheries and Aquatic Sciences
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• v.18 no.2
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• pp.115-121
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• 2015

This study was conducted to confirm quality properties of sterilized Ganjang-gejang (marinated crab Portunus trituberculatus) with Korean soy sauce using by gamma irradiation and to improve quality of sterilized Ganjang-gejang. The Ganjang-gejang was irradiated at dose of 3, 6, 9, 12, and 15 kGy by gamma irradiation and there was evaluated in microbiological, physicochemical, and sensory properties. Total aerobic bacteria and fungi contents of non-irradiated samples were about 6 and 4 log CFU/g level, respectively. Gamma-irradiated samples at above 9 kGy did not contain aerobic bacteria or fungi at detection limit less than 2 log CFU/g, but sensory scores were significantly decreased depending on the irradiation dose. To improve the sensory qualities of gamma-irradiated Ganjang-gejang, the temperature was adjusted during sample irradiation. When samples were irradiated under freezing temperatures, especially on dry ice, the TBARS and the deterioration of sensory qualities of Ganjan-Gejang were reduced. Different odor patterns were observed among samples, as observed using electronic nose analysis system. The results of this study indicated that treatment with irradiation under low temperatures may help to preparing high-quality Ganjang-gejang.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.52 no.3
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• pp.193-198
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• 2019

Natural seasoning are trends of food industries to replace synthesized seasoning due to consumer preference. However, unexpected results can be happened in a point of sensory evaluation and physico-chemical properties by adding natural seasoning such as reduced flavor, color change and so on. Therefore, this study aimed to verify the potential of sea tangle Saccharina japonica extract fermented by lactic acid bacteria (STE) for myungran (pollock roe)-jeot instead of present synthesized seasoning. Among various STE concentration (0%, 5%, 10%, and 15%) in myungranjeot, there was no significant physicochemical changes in a point of crude lipid, pH, total acidity, salinity and color difference. Microbiological profiles was also not significantly different. The 10% STE-myungran-jeot showed higher ${\gamma}$-aminobutyric acid (GABA) content as 24.4 mg/100g at free amino acid analysis than other STE-myungran-jeot without decline of sensory properties. In overall, it revealed that STE could replace the synthesized seasoning and improve the quality of Myungran-jeot. The results suggest that STE can be useful to develop a Korean traditional fermented food.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.4
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• pp.49-55
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• 2021

The purpose of this study was to compare the quality characteristics of each brown rice glutinous rice red pepper paste prepared. In this study, brown rice, glutinous rice, and red pepper paste were prepared with various enzyme preparations. A 20-day study of the physicochemical and microbiological properties of each enzyme through the results process showed significant differences. In particular, brown rice red pepper paste manufactured using cozies purchased from Sunchang was functionally superior to rice cozies and bean cozies, with probiotics of 7.1-7.5×107 CFU/mL, lactobacillus of 1.9-2.2×103 CFU/mL, 48.67-52.30%, and 58.57-63.90%. When the results were combined, the composition of microorganisms and enzymes of fermented soybean paste purchased from Sunchang was not confirmed, but brown rice chili paste with nutritional and functional properties could be prepared compared to A.oryzae and A. kawachii.

• Korean Journal of Organic Agriculture
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• v.19 no.3
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• pp.417-425
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• 2011

This study was conducted to investigate the changes in physicochemical and microbiological properties during fermenting process of farm-made organic liquid fertilizer made of the mixture of organic materials such as blood meal and molasse during fermenting process. The pH level of organic liquid fertilizer during the ermentation decreased from 7.2 to 4.3. The EC of organic liquid fertilizer was increased from 13.9 dS/m to 99.3 dS/m during the fermentation. The total population of aerobic bacteria decreased from $8.2{\times}10^5$ cfu/ml to $3{\times}10^4$ cfu/ml, but Bacillus spp. increased from $2.1{\times}10^2$ cfu/ml to $4.2{\times}10^3$ cfu/ml during the fermentation. Bacterial isolates were obtained from organic liquid fertilizers and identified by fatty acid-base typing. The Genus Bacillus was dominant as fermenting proceeded. The denaturing gradient gel electrophoresis (DGGE) profile showed changes of bacterial communities in organic liquid fertilizers.

• Food Science of Animal Resources
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• v.27 no.1
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• pp.42-46
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• 2007

We evaluated the microbial safety and quality characteristics of Korean slice beef jerky, and investigated these properties over 28-day and 90-day storage periods at room temperature ($25^{\circ}C$) and elevated temperature ($35^{\circ}C$). After microbial counts of all samples, mesophilic bacteria were detected at 1.23 Log CFU/g at day 0. Counts of mesophilic bacteria did not change significantly in all samples, and coliforms and Bacillus cereus were not detected in all samples during storage at either $25^{\circ}C$ or $35^{\circ}C$. TBA values, Aw, and pH were investigated. The Aw of korean slice beef jerky stored at room temperature was 0.71 at day 0, and was reduced to 0.61 after 90 days. The TBA value increased as storage time increased, and its TBA value was 0.48 after 90 days of storage. The pH of all samples did not change significantly. At $35^{\circ}C$ storage, TBA values, Aw, pH were not significantly different than those stored at $25^{\circ}C$. Also, the sensory properties of all samples were not significantly different between two storage temperatures. In conclusion, these results suggest Koran slice beef jerky ould be used as basic study for development of the commercial beef jerky.

• Korean Journal of Microbiology
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• v.44 no.4
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• pp.317-325
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• 2008

Recently there are difficulties in management of golf courses because of an ever increasing demand for golf as a leisure sports. Hence natural minerals as an amendment could be applied to improve and manage the physicochemical properties of the golf course soils in an environment-friendly way. In this study, quartz porphyry, which has been shown to be a good soil amendment for crop production, was tested for its effect on physicochemical properties of the golf course soil, growth of creeping bentgrass (Agrostis stolonifera) and changes of soil microbial communities in the soil. In general, amendment of 20% quartz porphyry into the soil turned out to be most effective in enhancing a proper growth of the grass leaves and roots. DGGE profile data showed that eubacterial species richness was also the highest at this level of the mineral treatment in which Actinobacteria and ${\alpha}$-Proteobacteria were the dominant phyla. This appeared to be attributed to a low level of soluble organic matter content and decreased concentration of cations such as $Ca^{2+}$, $Mg^{2+}$, and $K^+$.