• Korean Journal of Food Science and Technology
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• v.33 no.5
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• pp.567-573
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• 2001

Lactobacilli have been generally recognized as an important lactic acid bacteria present in the normal human intestinal flora. Fifty two Lactobacillus isolates were recovered from the feces of healthy Koreans whose age ranged from thirteen days after birth to 37 years. Among the isolates above, 17 isolates were tentatively identified as strains of Lactobacillus acidophilus and 3 isolates as strains of Lactobacillus casei. For their characterization, these twenty isolates were subjected to the experiments for the resistance to the artificial gastric juice, pH2.5 and bile salt. Interestingly, 3 strains survived pH 2.5 after 3 hour incubation in the artificial gastric juice with more than 75% of survival rate. L. acidophilus a-4 had the highest survival rate of 100%. Four strains including L. acidophilus a-3 grew gradually in MRS broth in the presence of the artificial bile salt. Cholesterol assimilation was also tested for the 20 isolates. The result showed that cholesterol concentration of the medium was reduced by 10 Lactobacillus isolates with more than 60%, as compared to the control. L. acidophilus a-2 had the highest reduction rate of 77%. Judging from these data obtained in vitro, some isolates ware likely to reach the lower small intestine after consumption without a significant loss of viability, suggesting that they had the potential to be developed as a probiotic culture which might lower the cholesterol level in human.

• Journal of Dairy Science and Biotechnology
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• v.37 no.2
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• pp.115-128
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• 2019

Lactic acid bacteria obtained from traditional Kimchi were selected on the basis of their caseinolytic activity and lactose usability and examined for availability as a starter in probiotic activity. Thirty-two strains were selected as lactic acid producing bacteria in BCP agar, and two strains (KC23 and KF26) with more than 90% resistance for both acid and bile salts were selected. The two strains were identified as L. plantarum (KC23) and L. paracasei (KF26) by API 50 CHL system and 16S rRNA sequence analysis. L. plantarum (KC23) was finally selected based on its biochemical characteristics for lactose and raffinose usability. Free tyrosine content increased rapidly in 10% skimmed milk medium, from $24.1{\mu}g/mL$ after 8 h to $43.9{\mu}g/mL$ after 16 h. Additionally, the caseinolytic clear zone of 12 mm of L. plantarum (KC23) was greater than the 9 mm zone of commercial L. acidophilus CSLA. The bacterium exhibited mesophilic growth and yielded $8.9{\times}10^8CFU/mL$ when incubated at $37^{\circ}C$ for 12 h at pH 4.25. Moreover, L. plantarum KC23 exhibited antibacterial activity as it formed a clear zone of 8-13 mm for the 5 pathogens. Adherent activity was 2.23 fold higher than that of LGG. The acidity of 10% skimmed milk fermented for 12 h was 0.74%.

• Korean Journal of Food Science and Technology
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• v.24 no.3
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• pp.209-214
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• 1992

In order to save foreign currency and to domesticize the dairy products, various fresh cheeses and whey drinks were developed and some physicochemical, microbiological and sensory evaluation were performed. The yield of fresh cheese was 22.3%, while that of whey 77.7%. The pH-values of fresh cheeses were $5.90{\sim}6.49$, while those of whey drinks $6.07{\sim}6.49$, and fermented whey drinks $3.97{\sim}4.91$. The acidities of fresh cheeses were $0.09{\sim}0.26%$, while those of whey drinks $0.09{\sim}0.36%$. The contents of solid substances, protein and lactose in fresh cheeses were $25.67{\sim}34.18%$, $7.45{\sim}9.11%$ and $3.61{\sim}4.14%$, while those of whey drinks $7.39{\sim}7.70%$, $0.88{\sim}0.94%$ and $4.93(\sim}6.17%$, respectively. The lactic acid contents of whey drinks varied from $0.01{\sim}0.38%$, where the content in the fermented sample was the highest. The general colony counts of fresh cheeses were $0{\sim}30/g$, while those of whey drinks $0{\sim}80/ml$. The psychrotrophs counts of fresh cheeses were $0{\sim}20/g$, while those of whey drinks $0{\sim}60/ml$. Lactic acid bacterial counts in both products were not detected except for $97{\sim}401{\times}10^8/ml$ in fermented whey drinks. E. coli and fungi were not detected in both products. In sensory evaluation of both products, the strawberry added fresh cheese was the best of fresh cheeses, while the garlic added fresh cheese was the worst. Pure whey drink was the best of whey drinks, while the ginseng added whey drink was the worst.

• Korean Journal of Microbiology
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• v.35 no.4
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• pp.307-314
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• 1999

This study was aimed at the investigation of the possibility of the addition of lactic acid bacteria as "starter"for the preparation of radish juice. Forty strains of lactic acid bacteria were isolated from dongchimi that was fermented by a traditional method. The isolates were assorted into 5groups, Leuconostoc mesenteroides subsp. mesenteroides (J-9), Lacobacillus brevis (J-12), Lactobacillus fermentum (J-7), Lactobacillus sake (J-20), and Lactobacillus plantarum (J-39). Leuconostoc mesenteroides was predominated in the sample of dongchimi with frequency of 52.5%. Each of the strain, which exhibited the beat growth in the species, was selected in the 5species, and investigation of the fermentation characteristcis was carried out. The fermentation were performed for 9 days at 25${\circ}C$ after the inoculation of 0.3% ($10^{6}$ cfu/㎖) to each ultra-filtrated radish juice. The pH, total acidity, content of non-volatile organic acids were examined during the fermentation period. Lactobacillus plantarum showed the highest growth rate and the growth rate of Lactobacillus sake was the lowest. The pH (6.3-6.36) and total acidity (0.09-1.0 %) fo the ultrafiltrated radish juice before fermentation were changed to 3.2-4.3 and 0.65-1.2% after 9days, respectively. The changes of the pH and total acidity were related with the growth of the lactic acid bacteria; the better growth of lactic acid bacteria, the more rapid decrease of pH and increase of the total acidity. when the amount of non-volatile organic acids were estimated during fermentation, citric acid, malic acid, malonic acid, and succinic acid were decreased in all cases. However, the content of lactic acid increased with the progression of fermentation. L. mesenteroides (J-9), L. brevis (J-12) and L. fermentum (J-7) were chosen for the candidates of the starter for the lactic fermentation of radish juice based on the biochemical analysis and sensory evaluation.

• Journal of agriculture & life science
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• v.50 no.4
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• pp.147-155
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• 2016

This study presented a measure for turning by-products, released from land farming sites, into resources. The measure involved adding food by-products such as rice bran and nonfat soybean to the sludge, released from the eel farming sites, inoculating the lactic acid bacteria, Aspergillus oryzae, and Bacillus subtilis by step, fermenting them, and measuring the changed ingredients of the fermented fodder. The water content of the fermented fodder by the step of preparation was the first-step fermented product (14.6%) using the lactic acid bacteria, and the second and third-stage fermented product (33.0% and 34.0% respectively) using Aspergillus oryzae and Bacillus subtilis. The pH level was found to be 5.38 in the first-step fermented product due to the secretion of lactic acid caused by the lactic acid bacteria, and the pH level of the second and third-stage fermented products was 5.66 and 7.26, respectively, showing that the pH level increased. The phytic acid content was 0.126g/100g in the first-step fermented product, 0.004g/100g in the second-stage fermented product, and 0.093g/100g in the third-stage fermented product. The measurement of nitrogen content revealed that the amino nitrogen content was high with 1226.37mg% in the second-stage fermented product, and a little lower with 710.18mg% in the third-stage fermented product. The ammonium nitrogen content increased from 0.988mg/kg in the first-stage fermented product to 1.502mg/kg in the third-stage fermented product. Total nitrogen content increased to 2.78% in the first-stage fermented product, 4.08% in the second-stage fermented product, and 4.85% in the third-stage fermented product. As fermentation continued with the three microbes, the phytic acid decreased, and the protein decomposition rate increased. Also, due to the 3 step fermentation, the low-molecule nitrogen ingredient content increased, suggesting that the fodder was developed to offer high digestion and absorption.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.8
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• pp.1118-1123
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• 2009

Brown-rice hydrolyzates with different degrees of hydrolysis (DH) were fermented using Leuconostoc mesenteroides (Ln. mesenteroides) KC51 strain at $30^{\circ}C$ for 15 hr. Changes in pH, titratable acidity, viable cell counts and phytate degradation during fermentation were investigated. The acid production was increased with increasing DH of brown-rice hydrolyzate. At high DH (48.2%), the pH and titratable acidity reached to pH 3.41 and 0.82% after 15 hr fermentation, respectively. Regardless of DH of brown-rice, however, the viable cell population of Ln. mesenteroides KC51 was slightly increased to $4.0\sim7.2{\times}10^8$ CFU/g during the 6 hr of cultivation. The phytate content in brown-rice hydrolyzates decreased with increasing DH of brown-rice hydrolyzates. The level of phytate was reduced to around 50% of initial concentration at high DH condition. When the fermented brown-rice was kept at $4^{\circ}C$, pH, titratable acidity and number of viable cells were nearly maintained for 14 days.

• Journal of Applied Biological Chemistry
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• v.54 no.1
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• pp.21-25
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• 2011

A lactic acid bacterial strain showing high acid production in saccharified-rice suspension was isolated from Kimchi. This strain was analyzed by API 50 CHL kit and 16S rRNA sequencing analysis and identified as Leuconostoc mesenteroides 310-12. Saccharified-rice suspension was fermented using L. mesenteroides 310-12 strain at $30^{\circ}C$ for 15 h. The changes of pH, titratable acidity and viable cell number during fermentation were determined. The pH and titratable acidity were reached to pH 3.57 and 0.40% after 15 h fermentation, respectively. The viable cell population of L. mesenteroides 310-12 was rapidly increased to $8.9{\times}10^8$ CFU/g during the 15 h of cultivation. The contents of lactic acid and acetic acid were determined to be 0.077% and 0.065% after 15 h fermentation, respectively. The rice-based fermented beverage was manufactured by blending L. mesenteroides 310-12 fermented broth and some food additives. When this beverage was stored at $4^{\circ}C$, the viable cells population was decreased to $1.0{\times}10^7$ CFU/g and pH was nearly maintained for 25 days.

• Journal of Nutrition and Health
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• v.12 no.1
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• pp.59-68
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• 1979

This work was carried out to detect the enterobacterial contamination in summer kimchies and their antagonis tic activity with lactic acid bacteria during kimchi fermentation. And obtained results were as in the followings. 1) Severe cases of enterobactrial contamination were found in every kimchi material and in the first step of summer kimchi fermention. 2) Some pathogenic or food poisonous strain of Salmonellaspp. was identified among the contaminated enterobacteria. 3) Pathogenic strains of Salmonella typhi, Shigella flexneri or E. coli which were added to kimchi fermention, were contineously detected for 10days at the temperature of $10^{\circ}C$. Food poisonous strain of Vibrio parahemolyticus was more resistant than the above stains in the kimchi fermentation. 4) And in summer condition(over $30^{\circ}C$) the added pathogenic strains of enterobacteria were also detected for 2 day at pH of 4.5 kimchi fermentation. 5) The antagonistic activity of enterobacteria in lactate buffer solution of pH 4.8 was more stron than that in the kimchi fermentation at $30^{\circ}C$ of summer condition. 6) According to the above results, sanitary washing processes for every kind of kimchi material (vegitables) are required to reduce the enterobacterial concentration which is usually contaminated. And some fermentation period is also required to avoid the possible kimchi food poisoning.

• Journal of Animal Science and Technology
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• v.50 no.2
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• pp.227-236
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• 2008

The objective of this study was to evaluate the effect of dietary lycopene supplementation on meat quality in Longissimus Muscle of Korean native pigs. Meat samples were obtained from pigs which had been fed with finishing pig diets containing basal diets(C), 200 ppm lycopene (T1), 400 ppm lycopene (T2), and 800 ppm lycopene(T3). Longissimus muslce pH was not influenced by feeding lycopene. Total microbial counts of treatments were significantly lower than those of control at 0 day of storage (p<0.05). Counts of lactic acid bacteria and coliform of T2 and T3 were significantly lower than those of control and T1 at 0 day of storage(p<0.05). Regardless of packaging, microbial counts increased as the storage period increased(p<0.05). While water-holding capacity (WHC) values of the treatments were lower than those of control, cooking losses values of treatments were higher than those of control (p<0.05). Therefore, it can be concluded that Korean native pigs fed lycopene supplemented diets affect the microbial counts and meat quality (volatile basic nitrogen, WHC and cooking loss) compared with conventional ones. These results may show a fundamental data on production of Korean native pork.

• Journal of the East Asian Society of Dietary Life
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• v.13 no.4
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• pp.305-312
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• 2003

The effect of addition of ethanol and/or organic acid on slowing down the fermentation of Mul-kimchi was tested by measuring the changes in pH, acidity and counting the number of microorganisms in kimchi fermentation, and sensory evaluation were carried out. The addition of 0~5％ ethanol to kimchi delayed the decrease of pH and the delaying effect during kimchi fermentation was dependent on the ethanol concentration used. The pH of kimchi without ethanol decreased from 5.7 to 4.13, however, the pH of the kimchi added with 5％ ethanol only from 5.8 to 5.14. The increase of acidity in kimchi with 5％ ethanol was only 0.5~0.6％, while that without ethanol was 0.7~0.8％. Among the organic acids tested, adipic acid was found to be most effective on the prevention of kimchi souring. The Mul-kimchi added 2％ ethanol together with 0.1％ organic acid showed similar effect to that of organic acid alone in the change of pH and acidity. By the sensory evaluation, Mul-kimchi with 0.1％ adipic acid and 2％ ethanol was selected the most desirable one except control without any addition. And the numbers of total microbes, lactic bacteria and yeast count, showed the most effective inhibition in Mul-kimchi with 0.1％ adipic acid and 2％ ethanol.