• Journal of the East Asian Society of Dietary Life
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• v.20 no.5
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• pp.743-750
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• 2010

The influence of various fermenting conditions using Saccharomyces cerevisiae, alone (Control, Single) and in combination with mixed lactic acid-producing bacteria (Combined 1, Mixed, Combined 2), including Bifidobacterium longum, Enterococcus faecium, and Lactobacillus acidophilus on flour sourdough preparation was examined. For the Combined 2 method, starters were incubated separately for 15 h, combined, and then further incubated for 10 h. Fermentation using Combined 2 improved the growth of mixed lactic acid-producing bacteria, but inhibited that of S. cerevisiae. This was also reflected in the extent of the pH reduction in sourdough produced in the Combined 2 step by these organisms. Among biochemical activities, $CO_2$ production and titratable acidity were increased by Combined 2, although the viable yeast counts were decreased. Aroma compounds in sourdough markedly varied according to fermentation conditions.

• Food Science and Biotechnology
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• v.17 no.4
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• pp.857-860
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• 2008

S-Adenosyl-L-methionine (SAM) is a bioactive material used in the treatment of depression, osteoarthritis, and liver disease. To obtain lactic acid bacteria (LAB) producing high concentrations of SAM, LAB were isolated from commercial kimchi and from prepared kimchi products that contained shrimp jeotgal (fermented salty seafood) or sand lance jeotgal or that were fermented at 5 or $10^{\circ}C$, respectively, when pH was 4.2 to 4.8 and titratable acidity 0.6 to 0.9. Among the 179 LAB strains isolated from the fermented kimchi products, the genus Leuconostoc produced the highest intracellular level of SAM (1.58 mM) and Lactobacillus produced the second highest level (up to 1.47 mM) in the strain culture. This is the first study to quantify SAM in LAB isolated from fermented kimchi prepared by a general kimchi recipe. Ultimately, the selected strains (Leuconostoc mesentroides subsp. mesenteroides/dextranicum KSK417, L. mesentroides subsp. mesenteroides/dextranicum KJM401, and Lactobacillus bifermentans QMW327) could be useful as starters to manufacture fermented foods containing high levels of SAM.

• Food Science of Animal Resources
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• v.39 no.5
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• pp.820-830
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• 2019

Most consumers consider yogurt to be a healthy food because it contains probiotic microorganisms. Although a plethora of commercially produced yogurts exists, nutritional and functional aspects of the commercial yogurts have not been well characterized. In this study, the microbiological and physicochemical properties of popular drinking yogurts in Korea were extensively characterized. The viability of lactic acid bacteria, including lactobacilli and bifidobacteria, varied between yogurt samples. These lactobacilli and bifidobacteria showed effective antimicrobial activities against foodborne pathogenic bacteria. Unlike the titratable acidity and pH, the soluble solids content varied between yogurt samples. All the yogurt samples contained high levels of potassium (average 143.53 mg/100 g) and calcium (average 133.92 mg/100 g), as well as phosphorus and sodium. Lactose, fructose, and glucose were the major sugar components in most yogurt samples, whereas the levels of sucrose and maltose were relatively low. Among several organic acids analyzed in the yogurt samples, lactic acid (average 767.67 mg/100 g) and citric acid (average 170.91 mg/100 g) were the most predominant. Taken together, this study provides preliminary information about the nutritional and functional characteristics of commercially available drinking yogurts.

• Journal of the Korean Society of Food Culture
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• v.28 no.4
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• pp.401-408
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• 2013

The objective of this study was to determine the quality characteristics of cabbage juice fermented by lactic acid bacteria from Kimchi (Leuconostoc mesenteroides, Lactobacillus sakei SL1103, Lactobacillus plantarum LS5, and mixed starter). Cabbage juice was inoculated with lactic acid bacteria and fermented at 30 for 72 hrs. Changes in lactic acid bacteria number, pH, titratable acidity, Brix, and color during fermentation were analyzed. After fermentation for 24 hrs, cabbage juice fermented by mixed starter showed the highest number of lactic acid bacteria (9.45 log CFU/mL). The pH of all cabbage juice also decreased to 3.88~4.19 sharply, while cabbage juice fermented by Lac. sakei SL1103 showed the highest Brix ($8.38^{\circ}Bx$). Cabbage juice fermented by mixed starter showed the highest L value (56.83). In the sensory evaluation, cabbage juice fermented by a mixed starter (Leu. mesenteroides, Lac. sakei SL1103, and Lac. plantarum LS5) showed the highest preferences in taste, flavor, and overall acceptability. Therefore, cabbage juice fermented by mixed starter (Leu. mesenteroides, Lac. sakei SL1103 and Lac. plantarum LS5) has the highest potential for the development of fermented cabbage juice as an excellent bioactive functional food.

• The Korean Journal of Food And Nutrition
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• v.32 no.5
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• pp.494-503
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• 2019

The purpose of this study was to investigate the quality and antioxidant properties of three fermented sweet potato cultivars (Shinyulmi, Hogammi, and Shinjami) using lactic acid bacteria. During the fermentation, the pH was lowered and the titratable acidity increased. The viable cell counts of lactic acid bacteria increased 8.44-9.62 log CFU/g. Organic acid content (especially lactic acid) of sweet potatoes increased by fermentation. Also, ${\gamma}$-Aminobutyric acid increased more than 8.6 times by fermentation in all samples. The total polyphenol and flavonoid contents of sweet potato, showed insignificant changes in all samples by fermentation. ABTS radical scavenging activity of all samples slightly decreased by fermentation, but not significantly. DPPH radical scavenging activity decreased slightly by fermentation except Shinyulmi. However, when compared with the varieties, Shinjami showed the highest activity. The reducing power of Shinjami decreased slightly by fermentation, but activity was the highest among all samples. Based on these results, most of the chemical properties and functionality of fermented sweet potato are retained after fermentation, although some antioxidant activity decreases. We suggest that three fermented sweet potato cultivars (Shinyulmi, Hogammi, and Shinjami) using lactic acid bacteria can be used in various applications because of their effective functional properties.

• Korean Journal of Food Science and Technology
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• v.31 no.1
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• pp.36-44
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• 1999

Samjangs which were prepared using magjang, traditional doenjang, and mixture of traditional doenjang and magjang were stored. Characteristics of the stored samjangs were investigated. Maximum titratable acidity was shown in traditional doenjang after 30 day of storage. Total sugar in samjangs decreased while reducing sugar increased to $11.45{\sim}12.35%$ from $8.44{\sim}9.29%$ after 40 days. Amino type nitrogen predominantly increased to $337.3{\sim}381.1\;mg%$ after 40 days from $48{\sim}53\;mg%$ of initial period of preparation. Among the free amino acids the content of glutamic acid $(202.6{\sim}464.6\;mg/100g)$ was highest and others were not too much changed. Forty two components including 7 alcohols, 4 esters, 13 acids, 6 aldehydes, 5 phenols, 3 pyrazines and others were found in samjangs. Ethanol, acetic acid ethyl ester and 2-phenylethanol were found in all treatments and ethanol, acetic acid ethyl ester, phenylacetaldehyde, butanoic acid, acetic acid, 3-methyl butanoic acid and 2,4-hexadienoic acid might be major volatile components considering of high peak area. 2-Phenylethanol, butandioic acid ethyl ester, butanoic acid and 2-methyl-2-butenoic acid were higher than other components in samjang with magjang while ethanol, acetic acid, 2,4-hexadienoic acid were in samjang with traditional doenjang and 3-methyl butanoic acid, acetic acid ethyl ester and methyl pentanoic acid were in the mixed treatment.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.1
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• pp.78-84
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• 1993

This study was conducted to investigate the effect of various polyethylene (PE) film packaging on the quality of strawberry during storage at low temperature. Gas composition in film was changed rapidly at early stage of storage and then kept at the level of 5~10% $CO_2$and 1~3% $O_2$. Weight loss and decay rate were low at 0.08mm PE film packed strawberries. Titratable acidity, pH and soluble solids were changed slightly during storage but its large difference according to film thickness was not observed. Decrease of flesh firm-ness and a value was restrained by PE film packaging. Free sugar of strawberry was composed of glucose and fructose in similar content and it was decreased a little during storage but the difference according to film thickness was not observed. The organic acids in strawberry were citric acid, malic acid, succinic acid, ascorbir acid, oxalic acid, tartaric acid and pyruvic acid and the major organic acid was citric acid. The contents of citric acid, malic acid, succinir acid and ascorbic acid were decreased and oxalic acid and tartaric arid were not changed during storage but pyruvic acid was increased in early stage and then decreased. These changes of organic acid were slight in packaged with 0.08mm PE film strawberry.

• Food Science and Preservation
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• v.16 no.6
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• pp.804-809
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• 2009

Recently, many Koreans have started to consume aged kimchi fermented long-term at low temperatures. In the present study, the effect of low temperature ($5^{\circ}C$) on pH, titratable acidity (TA), organic acid level, viable microbial cell count, amino acid concentration, and polygalacturonase activity (PG) during long-term fermentation (46 weeks) of kimchi, were evaluated. After 10 weeks of fermentation, kimchi had a pH of 4.1 and a TA of 1.0%, respectively after 46 weeks fermentation, these values were 3.9 and 1.3%, respectively. Lactic acid, the ratio of lactic acid to acetic acid, and the ratio of Lactobacillus species/Leuconostoc species in kimchi increased as fermentation progressed from 10 weeks to 46 weeks. However, total viable cell counts of aerobic bacteria, yeasts, Lactobacillus species, and Leuconostoc species, free amino acid levels, and PG decreased as the fermentation period was extended from 10 weeks to 46 weeks.

• Food Science and Preservation
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• v.9 no.3
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• pp.292-297
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• 2002

This studies were carried out to investigate the effect of Prunus mume Sie. extract on growth of lactic acid bacteria isolated from kimchi and preservation of kimchi. Prunus mums Sie. extract inhibited the growth of homofermentative lactic acid bacteria and heterofermentative lactic acid bacteria isolated from kimchi. In early storage stage, the pH of Prunus mume Sie. extract added kimchi(PEAK) was lower than that of control. The pH of PEAK was higher than that of control after 25 days of fermentation. Titratable acidity, viable cell of total bacteria and lactic acid bacteria of the PEAK were lower than that of control during fermentation. The sensory quality of 1% PEAK was similar to control at 10 days of fermentation But overall acceptability of 3% PEAK decreased compare with l% PEAK.

• Korean Journal of Food Science and Technology
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• v.37 no.6
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• pp.922-927
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• 2005

Total and individual organic acid contents of Malus domestica Borkh, cultivars, Tsugaru, Fuji Jonathan (Hong-Ok), and New Jonagold(Sin-Heung) apples, were investigated. Average titratable acidities measured by titration method and total organic acids content determined by HPLC were 241.64-444.52 and 364.23-680.80mg%, respectively. Average total organic acid contents were Jonathan 630.80mg%, New Jonagold 471.04mg%, Fuji 403.80mg%, and Tsugaru 364.23mg%, Contents of DL-malic, citric, fumaric, and quinic acid were 351.98 (Tsugaru)-579.88mg% (Jonathan), 2.14 (Fuji)-12.95mg% (Jonathan), 0.012 (Fuji)-0.060mg% (Jonathan), and 8.91 (Tsugaru)-14.20mg% (Fuji), respectively. Succinic acid was detected only from Jonathan (27.53mg%) and New Jonagold (5.20mg%), while maleic acid was not detected from all cultivars. Ratio of L-malic acid and DL-malic acid contents were 0.98-1.02 in all apple cultivars.