• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.8
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• pp.1070-1075
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• 2006

Food materials for kimchi manufacturing were treated by ozone or gamma irradiation to reduce the number of contaminated microorganisms before the manufacturing of kimchi. Counts of total aerobic bacteria, yeast and mold were $10^6{\sim}10^7 and 10^3{\sim}10^4\;CFU/g$ in the food materials, respectively. After treatment with ozone $(3{\sim}6\;ppm), the total aerobic bacteria were reduced to 1 log cycle or more, in a dose-dependent manner. In comparison, gamma irradiation was superior to ozone treatment. Especially, irradiation of 5 kGy fully eliminated the yeast and mold attached in the food materials for kimchi manufacturing. The contents of ascorbic acid and total and reducing sugar were not affected by ozone or gamma irradiation. Taken together, it is suggested that microorganisms contaminated on materials for kimchi manufacturing could be substantially reduced by ozone (up to 6 ppm) and gamma irradiation (up to 5 kGy), without effect on the nutritional contents.

• Journal of the Korean Society of Food Science and Nutrition
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• v.13 no.2
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• pp.188-192
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• 1984

In order to investigate the hygienic status of commercial red pepper powder, one sample was directly prepared from raw red pepper which was purchased at market and the other one was a commercial red pepper powder. They were used for the investigation upon the status of microbial contamination, effect of irradiation for sterilization and physicochemical changes during 3 months of storage. Total bacterial counts of commercial red pepper powders were 3.83 to $6.68{\times}10^6$ per gram and coliform group was shown to be positive in some products. Total bacteria and coliform group were sterilized by the irradiation of 9 kGy and 3 kGy, respectively and no microorganisms were grown up until 3 months of storage at room temperature. The $D_{10}$ values of total viable bacteria in red pepper powders were 1.52 to 1.58 kGy. Chemical components such as moisture, total and reducing sugars were slightly decreased during the storage period. The contents of capsanthin and capsaicin were partly affected by the high dose irradiation but the difference between unirradiated and irradiated groups was diminished with the elapse of storage period.

• Food Science and Preservation
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• v.15 no.3
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• pp.340-346
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• 2008

This study investigated the microbial safety of apple snails and intermediate-moisture-content apple snail products subjected to various treatments, according counts of total bacteria, Escherichia coli, mold and yeast during storage at 4C Heating of raw apple snails at 95C for 5 min increased the storage period in relation to total bacteria, E. coli, mold and yeast-cell growth. Addition of 10% NaCl and 50% vinegar increased the microbial safety of apple snails. Microorganisms were not detected for 14 weeks in vacuum-packaged intermediate-moisture-content apple snail products stored at either 4C or 30C. These results suggest that heat treatment of raw apple snails, soaking in 10% NaCl and 50% vinegar solutions, and vacuum-packaging increases the shelf-life and microbial safety of apple snail products.

• Food Science and Preservation
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• v.17 no.6
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• pp.793-799
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• 2010

Kimchi was fermented in permeability-controlled polyethylene containers, in glazed onggi (Korean ethnic earthenware) or glass bottles at $5^{\circ}C$ for 8 weeks. During 4 weeks of storage, kimchi fermented in the permeability-controlled container showed a stable fermentation pattern, in terms of changes in pH and acidity, compared with kimchi fermented in the other containers. With respect to changes in bacterial counts, kimchi fermented in polyethylene containers showed vigorous multiplication of lactic acid bacteria, especially Lactobacillus sp., but slow growth of total aerobic bacteria. The springiness of kimchi fermented in the polyethylene containers was optimal (about 10% more than that of glass bottle-fermented kimchi), and the overall acceptability and hardness of container-fermented kimchi were excellent upon sensory evaluation. The DPPH radical-scavenging activity of kimchi fermented in polyethylene containers was also greater (91%) than that of kimchi fermented in glazed onggi (73%) or glass bottles (63%). The $O_2$ and $CO_2$ permeabilities of the polyethylene containers were higher (458 and $357\;mmol\;h^{-1}\;m^{-2}\;atm^{-1}$, respectively) than were those of the other containers; the permeability ratio was 0.8. Glass bottles showed no permeance. The results indicate that permeability-controlled polyethylene containers may be used for kimchi fermentation.

• Food Science and Preservation
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• v.23 no.7
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• pp.939-944
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• 2016

The aim of this study was to establish an optimum blanching condition for outer cabbage leaves to increase utilization of the byproduct. Outer leaves of Kimchi cabbages were cut to size ($4{\times}4cm$) and blanched at 80, 90, $100^{\circ}C$ for 1, 3, and 5 min. Subsequently, weight loss, pH, total bacteria, coliform and texture properties were investigated. Sensory evaluation of a ready-to-cook soup prepared from blanched outer leaves was investigated to determine whether the quality of the blanched outer leaves was acceptable. Both weight loss and pH of outer leaves of Kimchi cabbage were increased by blanching. Compared to raw samples, total bacterial counts decreased and coliform bacteria were not detected. The hardness of raw leaf samples was $1.5kg{\cdot}force$ (N). Sample hardness was 18.7~21.7% lower after blanching for 3 min and 34.8~36.7% after blanching for 5 min. Sensory evaluation of outer leaves blanched at $100^{\circ}C$ for 5 min revealed significant differences from the other treatments (p<0.05). In addition, sensory evaluation scores for texture and appearance of outer leaves blanched at $100^{\circ}C$ for 3 min were higher than those for commercially available products. The results of this study indicate that blanching can be effective for developing a food product from the outer leaves of Kimchi cabbage.

• Korean Journal of Food Science and Technology
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• v.37 no.2
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• pp.274-278
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• 2005

Contamination levels of total aerobic bacteria, coliforms, Escherichia coli, Staphylococcus aureus, and Bacillus cereus In commercial Samgakkimbabs and sandwiches from southern Gyeounggi-do were monitored. Total aerobic bacteria counts in Samgakkimbabs and sandwiches were 3.50-5.54 and $3.88-6.29log_{10}CFU/g$, for coliforms 1.25-317 and $1.53-5.08log_{10}CFU/g$, for S. aureus 0.30-5.20 and $0.10-4.18log_{10}CFU/g$, and for B. cereus 0.88-2.48 and $0.22-2.18log_{10}CFU/g$, respectively. E. coli was not isolated from all Samgakkimbabs and sandwiches except from one sample of sandwich salad ingredient. Results indicate hygiene of commercial Samgakkimbabs and sandwiches was deleterious.

• Korean Journal of Food Science and Technology
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• v.48 no.1
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• pp.9-14
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• 2016

Recently, the market for ready-to-use vegetables has increased largely due to consumer demands, which led to the production of minimally-processed frozen crushed garlic products. This study was designed to determine the effect of electron beam irradiation (0-7 kGy) on microbial decontamination, bioactive compounds, and antimicrobial activities of frozen crushed garlic obtained from Korea and China. The microbial counts (total bacteria, yeasts & molds) were reduced from log 3-4 CFU/g to non-detectable levels as a result of irradiation at 4 kGy. Irradiation treatment at 4 kGy did not affect the amount of alliin, allicin, total pyruvate, and total thiosulfinate of crushed garlic, however, this dose induced insignificant changes in antibacterial activities against pathogenic bacteria including Bacillus subtilis, Staphylococcus aureus, Salmonella enteritidis, Vibrio parahaemolyticus, and Yersinia enterocolitica. Therefore, electron beam irradiation less than 4 kGy can be considered suitable to improve the microbial decontamination without altering the biological activity of frozen garlics.

• Korean Journal of Food Science and Technology
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• v.28 no.1
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• pp.137-145
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• 1996

Chemical changes, lactic acid bacteria and yeast counts in kimchi prepared by a commercial manufacturer in large scale were monitored at different fermentation temperature. The optimum pH of kimchi, around pH 4.2, reached within 2 days at $25^{\circ}C$, 3 days at $15^{\circ}C$ and 23 days at $5^{\circ}C$ fermentation, respectively. The optimum acidity calculated as lactic acid was not exactly coincident with pH. The total viable count reached at maximum within 2 days at $25^{\circ}C$, 6 days at $15^{\circ}C$ and 12 days at $5^{\circ}C$ fermentation, respectively. The identified strains of Lactobacilli during kimchi fermentation were L. brevis, L. plantarum and L. acidophilus with 3 unidentified strains. L. brevis, L. plantarum appeared from the first stage of fermentation to the terminal at $15^{\circ}C$ and $25^{\circ}C$ with keeping a constant level of viable number. In case of Leuconostoc species, L. mesenteroides subsp. mesenteroides was identified. This strain increased in viable number at the beginning of fermentation and dropped sharply at all fermentation temperatures. Pediococcus species including P. pentosaceus and one unidentified strain increased at the first stage of fermentation and decreased after on. Streptococcus faecium subsp. casseliflavus which appeared at the middle stage and Aerococcus viridans which was sole strain were also confirmed during kimchi fermentation. Cryptococcus laurenti was identified at all fermentation temperature and disappeared at the first stage of fermentation. It was reappeared 10 days only after fermentation at $25^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.32 no.2
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• pp.410-416
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• 2000

Changes in microflora and enzyme activities of three kinds of kochujang were investigated during 6 months of fermentation. Three different kinds of kochujang were prepared using Aspergillus oryzae, Aspergillus oryzae plus Bacillus licheniformis and Aspergillus oryzae, Bacillus licheniformis plus Saccharomyces rouxii. The pH of kochujang showed a slight decrease during fermentation. The number of mold and bacteria increased up to 30 days of fermentation and then decreased rapidly thereafter and the numbers of yeast increased after 30 days of fermentation. The viable cell counts of anaerobic bacteria increased remarkably up to 30 days of fermentation and then decreased to 60 days of fermentation. The activities of ${\alpha}-$, ${\beta}-\;amylase$ and protease were the highest in kochujang prepared with Aspergillus oryzae plus Bacillus licheniformis.

• Journal of agriculture & life science
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• v.44 no.2
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• pp.49-56
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• 2010

Yogurt base was prepared from skim milk added with 0.1, 0.3 and 0.5% (w/v) garlic powder and fermented with Lactic acid bacteria (the mixed strain of Streptococcus thermophilus, Lactobacillus delbrueckii subsp. bulgaricus) at $42^{\circ}C$ for 24 h. The yogurt products were evaluated for acid production such as pH and titrable acidity, number of viable cell, viscosity, color value and sensory properties. The titrable acidities of yogurt added with garlic powder were higher than that of control(0.73%). There was no significant difference in viable cell counts among samples except 0.3% garlic powder. The viscosity of 0.5% garlic yogurt was the highest than any other garlic yogurt. There was no significant difference in color difference among experimental groups. The overall sensory scores of yogurt added with 0.1% and 0.3% garlic powder were not significantly different with those of control. These results suggest that the added amounts of garlic powder to prepared yogurt are adequate below 0.3%.