• Microbiology and Biotechnology Letters
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• v.22 no.5
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• pp.467-476
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• 1994

Lactobacillus casei HY 2782, prophage cured strain was characterized to be stable as much as L casei YIT 9018, parent strain. By southern hybridization, it was confirmed that the temperate phage was incorporated in chromosomal DNA of L. casei YIT 9018 as a prophage. It was also proved that the prophage was cured from chromosomal DNA of L casei HY 2782. The growth rate, lactic acid producing ability, carbohydrates fermentation, and enzymatic activity of L. casei HY 2782 were found to be similar to those of L. casei YIT 9018. When L casei HY 2782 was used as a host, the multiplicity of infection (M.O.I.) of the temperate phage for L. casei HY 2782 was 1.0~5.0. Restriction enzyme analysis of pLC90 plasmid from L. casei HY 2782 was shown that the size was an approximately 68.22 kb. The plasmid profiles, genomic DNA patterns, and cellular fatty acids composition of L. casei HY 2782 were similar to those of L casei YIT 9018. And the major fatty acids composition of these strains were C$_{14;0}$,C$_{16;1}$, C$_{16;0}$, C$_{18;1}$ and C$_{19;cyclo-}$ 10 sets of arbitrary primer in the PCR were screened to find differentiation against two strains of L. casei. Among them, b$_{5}-1/17-1 primer was produced an approximately 1.3 kb DNA band of only L casei YIT 9018. And b$_{5}-2/17-2 primer was produced an approximately 1.0 kb DNA band of only L casei HY 2782.

• The Korean Journal of Food And Nutrition
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• v.29 no.5
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• pp.677-683
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• 2016

To enhance the physiological activities and reduce the off-flavor of garlic in kimchi, we manufactured kimchi seasoning replaced with 25~75% black garlic, we evaluated microbiological, physico-chemical and sensory evaluation. The changes of total aerobic and lactic acid bacteria were similar between the control and the kimchi seasoning replaced with black garlic during storage periods. The lightness of the kimchi seasoning replaced with black garlic was lower than that of the control and decrease of lightness was proportional to the concentration of black garlic. The redness and yellowness of the kimchi seasoning replaced with black garlic were decreased to the concentration of added black garlic and changes of the redness in all the samples were slightly increased during storage periods. But the yellowness did not change during storage periods. The changes of pH and acidity did not differ between the control and the samples of replaced with black garlic during storage periods. The sensory parameters including taste and flavor did not differ among treatments during storage periods. But color and overall acceptance of the control and sample replaced with 25% black garlic were higher than those of the samples replaced with 50 and 75% black garlic.

• Korean journal of food and cookery science
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• v.29 no.5
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• pp.599-603
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• 2013

Tarak is our own traditional fermented milk made through lactic acid fermentation by using makgeolli as inoculum for milk or using already made tarak as inoculum but it is hardly known to people as its related studies are also insufficient. Accordingly, the purpose of this study was to manufacture jelly by using tarak and analyze its quality characteristics for the diversification of consumption promotion and demand of traditional fermented milk tarak. Tarak jelly that was made according to the percentage of adding tarak showed a tendency that the content of crue protein, crude fat and crude ash except for moisture water meaningfully increased as the amount of tarak added increased (P<0.05). In the case of pH, it declines as the amount of tarak added was high. The chromaticity measurement result of tarak jelly was 54.32 in the case of control group for L, and it increased as the amount of tarak added increased. In the case of a, it decreased as tarak was added, whereas b meaningfully increased. There was meaningful difference between samples in the case of chewiness, fracturability and adhesiveness (p<0.05). The sensory test result showed that there was meaningful difference between samples in their appearance and taste but there was no meaningful difference in the case of overall preference, scent and texture.

• Korean Journal of Pharmacognosy
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• v.47 no.3
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• pp.273-279
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• 2016

This study evaluates the tyrosinase, elastase inhibitory and antioxidant activities of isolated Lactobacillus rhamnosus fermented extracts of Phragmites communis Trinius. After culture for 4 days at $30^{\circ}C$ using 1% P. communis extract, the cell mass of L. rhamnosus reached $1.4{\times}10^{10}CFU/mL$. The number of cells on P. communis extract and MRS medium was similar. This results indicated that P. communis extract can be used as an economical medium for industrial lactic acid bacteria production. The fermented P. communis extract exhibited 4 fold higher tyrosinase inhibitory effect than non fermented P. communis extract. The non fermented P. communis extract has no inhibitory effect on elastase. However the fermented P. communis extract show high inhibitory effect on elastase ($IC_{50}$; $249{\mu}g/mL$). These results indicated that the fermented P. communis extract can potentially be used for developing new cosmetic or health food ingredients.

• Korean Journal of Food Science and Technology
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• v.21 no.6
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• pp.820-825
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• 1989

Yukwa (one of most popular Korean traditional popped rice snacks) was made by four different varieties of rice, Shinsun (Japonica) and Hangang $(Japonica{\times}Indica)$ which are waxy rice and Dongjin (Japonica) and Samgang $(Japonica{\times}Indica)$ which are non waxy rice, for their quality by total expansion volume, hardness and brittleness. It was notified that hydration rate of waxy and non waxy rice for preparation of Yukwa were different by 30% and 42% in moisture content respectively soaked at $12^{\circ}C$ for 12 hours and the gelatinization temperature of their starch was $64.5-67.5^{\circ}C$ with no big difference by varieties. The quality of Yukwa was deeply related with amylose contents ranging from 18.5% of non waxy rice to 2-3% of waxy rice. Superior quality (p<0.05) was got from waxy rice. Lactic acid bacterial fermentation didn't improve the quality, and soybean and rice bran oil can be used for popping in even value.

• The Korean Journal of Food And Nutrition
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• v.29 no.2
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• pp.162-170
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• 2016

The effects of dietary ${\beta}$-glucan, obtained from bacterial fermentation, on the intestinal mass, short chain fatty acids, lactate production and pH in Sprague-Dawley (SD) rats were evaluated. SD rats fed with 0% (control group), 1% or 5% ${\beta}$-glucan supplemented diets (w/w) for 3 weeks. The presence of ${\beta}$-glucan in the diets resulted in a significant increase in colonic contents in a dose dependent manner. The amount of short chain fatty acids increased in rats fed ${\beta}$-glucan diets. Rats fed the 5% ${\beta}$-glucan diets had higher levels of acetate, propionate and butyrate by 1.8, 1.7 and 3.0 fold of the control group in the cecum, and 2.2, 2.9 and 3.1 fold of the control group in the colon, respectively. The ${\beta}$-glucan diets also significantly increased the levels of cecal and colonic lactate by 1.4~3.4 fold, when compared to the control diet, indicating that dietary ${\beta}$-glucan stimulated the growth of lactic acid bacteria within the intestine. These results suggest that dietary ${\beta}$-glucan, by providing short chain fatty acids and reducing the cecal and colonic pH, may be beneficial in improving gut health, and provide evidence for the use of ${\beta}$-glucan as a dietary supplement for human consumption.

• Korean Journal of Microbiology
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• v.39 no.3
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• pp.192-196
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• 2003

To obtain large pools of lactic acid bacteria, a strain was isolated from Tongchimi. Through its sugar fermentation and analysis of 16S rRNA gene, it was identified to be Lactobacillus plantarum HB1. This strain is Gram-positive and catalase-negative. In the range of 1～88 bp in the HB1 16S rRNA gene, the HB1 strain was homologous with other L. plantarum strains by almost 100%, and in the range of the rest 32 bp, the HB1 strain showed considerable variation, compared to other strains. Nitrate which may exist in radish can be easily converted to nitrite. The nitrite interacts with amine, and becomes nitrosamine which may cause stomach cancer. The culture obtained by HB1 strain could eliminate 400 ${\mu}M$ nitrite within 1.5 hr. It is necessary to isolate specific components which are involved in nitrite elimination in the culture and to study on its mechanism.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.2
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• pp.216-221
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• 2007

Microbiological, chemical and sensorial quality changes of kimchi, which was manufactured with sanitized materials by ozone and gamma irradiation, were investigated during storage. The number of total aerobic bacteria in control was increased rapidly by storage and decreased after 10 days of storage. However, the kimchi which was manufactured with materials treated with ozone or gamma irradiation showed a lower rate of increase. The number of lactic acid bacteria was lower in control than in treatments. Gamma irradiation of 3 or 5 kGy showed the lowest change of microbial population in kimchi during storage. pH, acidity and sensory quality were also rapidly changed in control whereas those of ozone or irradiation treated sample was slower. Therefore, cold pasteurization of materials before kimchi manufacturing provide a slower fermentation, resulting into the extension of storage quality for kimchi.

• Food Science and Preservation
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• v.23 no.7
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• pp.967-976
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• 2016

The objective of the present study was to investigate differences in quality of kimchi products produced in Korea, Japan, and China. Kimchi products from kimchi-producing countries with high consumer consumption such as Japan and China along with local products from Korea, where exporting has not yet started, were collected. Product pH, acidity, salinity, package pressure, gas production were assessed, and microbiological analyses and sensory evaluations were performed on kimchi products that were stored at either $4^{\circ}C$ for 63 d or $15^{\circ}C$ for 20 d. The pH and acidity results showed that as Japanese and Chinese kimchi had higher pH and lower acidity than that of Korean kimchi, which was determined to be indicative of insufficient microbial fermentation following kimchi production. Japanese kimchi had different microbial properties than those of Korean kimchi, which is due to differences in their manufacturing processes. Overall preferences derived from sensory evaluations were: Korean kimchi>Chinese kimchi>Japanese kimchi. The results of this study demonstrate the sensory superiority of Korean kimchi and may be useful when predicting consumers' acceptance level of Korean kimchi exported to other countries.

• Journal of the Korean Society of Food Culture
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• v.30 no.6
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• pp.757-765
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• 2015

The objective of this study was to determine the quality characteristics of fermenting mash and pasteurized ginseng Makgeolli added with different concentrations of ginseng powder. Total aerobic bacteria and lactic acid bacteria counts of mash added with 0, 1, 2, and 4% ginseng powder during 4 days of fermentation significantly increased, whereas yeast count decreased. Viable cell count remarkably decreased after pasteurization. Pasteurized 4% ginseng Makgeolli (4.30) showed a higher pH than 0, 1, and 2 % ginseng Makgeolli (4.09, 4.08, and 4.06, respectively) after 15 days of aging. After aging, amylase activity of pasteurized Makgeolli decreased, and 0% and 1% ginseng Makgeolli (22.35, $21.55^{\circ}Brix$) showed higher Brix content than 4% ginseng Makgeolli ($20.15^{\circ}Brix$). Before aging, alcohol contents of 0, 1, 2, and 4% pasteurized ginseng Makgeolli were 5.80, 5.50, 5.20, and 5.10%, respectively. After 15 days of aging, 0% ginseng Makgeolli (7.00) showed higher alcohol content than 1, 2, and 4% ginseng Makgeolli (5.90, 5.80, and 5.60%, respectively). The results of the sensory evaluation show that 2% ginseng Makgeolli after 3 days of aging at $4^{\circ}C$ had the highest scores for taste (5.19), flavor (5.04), and overall acceptability (5.22) among the samples.