• Korean Journal of Food Science and Technology
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• v.35 no.3
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• pp.386-392
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• 2003

Physicochemical and microbiological changes of grape wine fermented and aged at 25 and $15^{\circ}C$ for 2 and 14 weeks, respectively, were investigated. Viable bacterial cell number, $3.3{\times}10^2\;CFU/mL$ at the beginning of fermentation, increased to $2.3{\times}10^6\;CFU/mL$ after 2 weeks, then decreased to $1.9{\times}10^3\;CFU/mL$ after 14 weeks. Viable yeast cell number increased from $2.8{\times}10^2\;to\;2.2{\times}10^7\;CFU/mL$ during fermentation, then decreased to $1.6{\times}10^4\;CFU/mL$ after aging. Turbidity, pH, total sugar content, reducing sugar content, and solid content of grape wine decreased during fermentation, whereas acidity and alcohol content increased to 0.64 and 8.4%, respectively. Most physicochemical properties did not change significantly during aging. When grape wine was filtered through $0.45-{\mu}m$ nitrocellulose membrane, followed by various ultrafiltration membranes with different molecular weight cut-off values, Biomax 100K membrane with $100\;L/m^2/hr$ (LMH) of initial flux was chosen for ultrafiltration process. These membrane filtration treatments resulted in complete removal of microorganisms and decreases in turbidity, reducing sugar, and solid content. Physicochemical properties of wine did not change, and no microorganisms were found during storage at $30^{\circ}C$ for 12 weeks.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.3
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• pp.213-220
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• 2018

This study was conducted to investigate changes in the quality of Gochujang following the addition of sea tangle Saccharina japonica powder fermented by lactic acid bacteria (FSP). Gochujang was prepared with or without FSP and fermented at $16^{\circ}C$ for 24 weeks, as detailed in a previous study. No significant physicochemical changes in moisture, crude protein content, pH, salinity and amino nitrogen content were observed among the varieties of Gochujangs evaluated (Commercial Gochujang, Gallic-Gochujang and FSP-Gochujang). In addition, we detected no significant differences in microbiological profiles. However, following addition of FSP to Gochujang, the color was affected and antioxidant properties were enhanced. The DPPH radical scavenging activity of FSP-Gochujang increased by 58.8% and 24.8% compared with Commercial Gochujang and Gallic-Gochujang, respectively. Furthermore, analysis of the free amino acid content revealed higher levels of ${\gamma}$-Aminobutyric acid (100.9 mg/100 g), a biofunctional ingredient, in FSP-Gochujang. Thus, these results suggest the potential for development of a traditional Korean fermented food with enhanced antioxidant activity and ${\gamma}$-Aminobutyric acid content using FSP.

• Food Science of Animal Resources
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• v.37 no.6
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• pp.804-812
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• 2017

This study was carried out to determine the physicochemical, microbiological, and quality characteristics of a new type of fermented sausage manufactured by incorporating Baechu-kimchi powder and gamma-aminobutyric acid (GABA)-producing lactic acid bacteria (LAB). The LAB count was at the maximum level by day nine of ripening in inoculated sausages, accompanied by a rapid decrease in the pH. The addition of kimchi powder decreased the lightness ($L^*$) and increased the redness ($a^*$) and, yellowness ($b^*$) values, while also significantly increasing the hardness and chewiness of the sausage (p<0.05). Moreover, although the thiobarbituric acid reactive substances values increased in all samples during the study period, this increase was lower in the kimchi-treated samples, indicating a reduction in lipid oxidation. Overall, our results show that the addition of Baechu-kimchi powder to sausages reduced the off-flavor properties and improved the taste profile of the fermented sausage in sensory evaluations. The GABA content of all fermented sausages increased from 17.42-25.14 mg/kg on the third day of fermentation to 60.95-61.47 mg/kg on the thirtieth day. These results demonstrate that Baechu-kimchi powder and GABA-producing LAB could be functional materials in fermented sausage to improve quality characteristics.

• 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.

• Food Science of Animal Resources
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• v.38 no.4
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• pp.749-758
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• 2018

The objective of this study was to provide preliminary data for food industry by investigating the distribution of microorganisms in raw materials and sausage examining the effect of heating temperature on sausage quality. Total microbes in sausage ranged 2.21-3.11 Log CFU/g. Bacillus pumilus, B. licheniformis, Staphylococcus saprophyticus, and Enterococcus faecalis were detected on sausage. Total microbes in raw materials was 1.59-7.16 Log CFU/g. Different types of microorganisms were found depending on raw materials, with B. pumilus and B. subtilis were being detected in both raw materials and sausage. Total microbes in sausage after heating was in the range of 1.10-2.22 Log CFU/g, showing the trend of decrease in total microbe with increasing heating temperature, although the decrease was not significant. With increasing heating temperature, pH and hardness were also increased. The yield of sausage manufactured at $85^{\circ}C$ was 95.42% while that manufactured at $65^{\circ}C$ was 96.67%. Therefore, decreasing heating temperature during sausage production might increase yield and save energy without microbiological effect.

• 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.

• 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.

• The Korean Journal of Food And Nutrition
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• v.27 no.5
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• pp.785-795
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• 2014

This study was conducted to develop low-salinity Kimchi with acetic acid, starters and fruits added for health and taste. The quality characteristics of the developed Kimchi by storage period and salt concentrations were investigated herein. The effects of salinity and fermentation temperature ($0^{\circ}C$, $5^{\circ}C$) on the quality characteristics of low-salinity Kimchi were investigated through physicochemical and microbiological analysis. The sensory characteristics are shown in the results below. The pH and acidity were quickly changed by higher temperature over longer storage periods, with gradual decrease in the pH accompanied with an increase in acidity. The microbiological analysis revealed increase in the total cell number regardless of the concentration and strain added during the storage period. Finally, test of the overall acceptability with regard to sensory characteristics according to the different strain sets in low-salinity Kimchi showed the average score for smell, salty taste and overall acceptability were highest in the hetero-fermentation strain group.

• Food Science and Preservation
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• v.17 no.4
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• pp.494-499
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• 2010

Pasteurization by radiation was performed to improve the microbiological quality of fresh yam juice. Samples were irradiated at doses of up to 5 kGy and microbiological, physicochemical, and sensory qualities were investigated during storage at 5oC for 8 days. Total aerobic bacterial, coliform bacterial, and yeast and mold counts in pre-irradiation samples were 7.09, 6.91, and 3.42 log CFU/g, respectively. Total aerobic bacterial and coliform counts fell significantly, in a dose-dependent manner, after irradiation, and these organisms were completely eliminated after 1 day of storage when 3 kGy or 5 kGy of radiation was applied. Yeast and molds were eliminated by irradiation at 3 kGy. Irradiation reduced sample viscosity. The $L^*$ value decreased after irradiation, whereas the $b^*$ value rose. Sensory evaluation testing revealed no significant difference between control samples and those irradiated with 1 kGy, except in color and texture, but sensory scores fell when irradiation of 3 kGy or over was employed, except in the taste domain. The results indicate that gamma irradiation with 1 kGy is effective to ensure the microbiological safety of fresh yam juice, without significant alteration in sensory characteristics, although further work should seek to reduce the detrimental effects of irradiation.

• Food Science of Animal Resources
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• v.30 no.2
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• pp.328-335
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• 2010

The aim of our study was to develop a new starter culture for fermented milk. Polymerase chain reaction screening of 103 acid-producing isolates from Kimchi identified 72 Lactobacillus strains. The ability of the strains to inhibit the growth of the food-borne human pathogens (Escherichia coli, Salmonella Enteritidis, Staphylococcus aureus) was measured, using a conventional paper disk method. Among the 72 strains, strain LHC52 displayed potent antagonistic activity. Use of 16S rDNA sequencing and the API 50CHL system identified the strain as Lactobacillus plantarum and it was designated L. plantarum LHC52. Biochemical analyses revealed especially high antibacterial activity against E. coli. Yogurt produced using L. plantarum LHC52 did not show different microbiological and physicochemical properties compared to conventionally-prepared yogurt, implicating L. plantarum LHC52 as a useful, potently antibacterial starter culture for yogurt preparation.