• Microbiology and Biotechnology Letters
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• v.46 no.4
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• pp.416-424
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• 2018

Vinegar was prepared from the fruits produced in Gangwon province, and major metabolite and aroma components were investigated for acetic acid fermentation. In the case of Meoru-Bokbunja vinegar, the ${\text\tiny{L}}$-alanine content was greatly changed by acetic acid fermentation. Acetic acid had the highest content (43%) of total aromatic components, and the contents of ester compounds, such as ethyl acetate and isoamyl acetate, were significantly increased after fermentation. Omija-Makgeolli vinegar produced linalool and hexanoic acid by fermentation, and terpenoid compound was prevalent (41.5%). ${\text\tiny{L}}$-alanine was also increased in Omija-Makgeolli vinegar, similar to that of Meoru-Bokbunja vinegar. Terpene compounds, such as terpinel-4-ol and ${\alpha}$-terpineol in Omija-Makgeolli vinegar, and ethyl acetate in Meoru-Bokbunja vinegar, were identified as major components in each aromatic formulation.

• Microbiology and Biotechnology Letters
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• v.42 no.2
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• pp.106-113
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• 2014

For the development of high value consumables utilizing jujube and grape, we investigated the biological activities of a variety of existing fermentation products of jujube and grape. The results revealed that ethanol fermentation products of jujube and grape had a higher antioxidative activity than acetic acid fermentation products. In addition, the ethanol fermentation products of jujube (JEF) had the highest antioxidative activity, with it being greater than that of the ethanol fermentation products of grape (GEF), the acetic acid fermentation products of jujube (JAF) and the acetic acid fermentation products of grape (GAF). As regards tests on whitening effects, JEF exhibited the highest tyrosinase inhibition effects amongst the test groups. However, when immunofluorecence was employed, JAF was seen to inhibit the expression of proteins related to the whitening effect. In the lipopolysaccharide-stimulated mode peritoneal macrophage model, all tested groups of fermentation products (JEF, GEF, JAF and GAF) suppressed nitric oxide production dose-dependently, with ethanol fermentation products demonstrating a higher nitric oxide expression inhibition effect than acetic acid fermentation products. When subjected to antibacterial activity tests, GAF exhibited antibacterial activity against all tested strains except Propionibacterium acnes. Both GAF and JEF revealed high antibacterial activity against Escherichia coli.

• Mycobiology
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• v.47 no.2
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• pp.250-255
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• 2019

In the present study, we aimed to determine the cause of surface film formation in three rice vinegars fermented using the traditional static fermentation method. The pH and total acidity of vinegar were 3.0-3.3 and 3.0-8.7%, respectively, and acetic acid was the predominant organic acid present. Colonies showing a clear halo on GYC medium were isolated from the surface film of all vinegars. Via 16S rDNA sequencing, all of the isolates were identified as Acetobacter pasteurianus. Furthermore, field-emission scanning electron microscopy analysis showed that the bacterial cells had a rough surface, were rod-shaped, and were ${\sim}1{\times}2{\mu}m$ in size. Interestingly, cells of the isolate from one of the vinegars were surrounded with an extremely fine threadlike structure. Thus, our results suggest that formation of the surface film in rice vinegar was attributable not to external contamination, to the production of bacterial cellulose by A. pasteurianus to withstand the high concentrations of acetic acid generated during fermentation. However, because of the formation of a surface film in vinegar is undesirable from an industrial perspective, further studies should focus on devising a modified fermentation process to prevent surface film formation and consequent quality degradation.

• Korean Journal of Food Science and Technology
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• v.53 no.6
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• pp.761-767
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• 2021

Strawberries fermented with Acetobacter pasteurianus SRCM60009 were prepared, and the quality characteristics and physiological activity were measured. As the fermentation period increased, viable cell counts increased, pH decreased, and total acidity increased from 1.09% to 4.20%. The organic acid content of strawberry through acetic acid fermentation was confirmed in the following order: acetic acid, succinic acid, citric acid, and lactic acid. Measurement of α-glucosidase and pancreatic lipase inhibitory activities and angiotensin converting enzyme inhibitory activity showed significantly increased physiological activity owing to fermentation. The use of strawberry vinegar as a functional material was confirmed by measuring the anti-diabetic, anti-obesity, and anti-hypertensive physiological activities through acetic acid fermentation of strawberry. Thus, fermented strawberry vinegar can be used as a functional material in vinegar and other foods.

• Food Science and Preservation
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• v.8 no.2
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• pp.151-156
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• 2001

Acetic acid solution containing calcium (AC) was added to kimchi seasonings by 10% and 205, and heat treatment at 70$\^{C}$ for 15 min was also tried, respectively. Kimchi with treated seasonings was investigated for the quality during fermentation at 10$\^{C}$. Heat treatment with 20% AC showed a retarded decrease pH than others on 10 days, but there was no great difference after 14 days. Higher titratable acidity was revealed in kimchi with AC during the fermentation. Total microbial lead and lactic acid bacterial count were generally lower in kimchi with AC. Reducing sugar content was maximum for all samples on 5 days, and then decreased thereafter. Redness of control kimchi was steadily increased during fermentation, but was lower than those of other treatments.

• KSBB Journal
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• v.13 no.4
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• pp.461-467
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• 1998

A fermentation system was supplemented with a device for the measurement of the durations of alkali pump feeding for automatic pH control and an A/D convertor for precise monitoring of pH value by computer. A software program was developed to measure buffer capacities from the pH signal and the pH control signal during fermentation. By measuring the buffer capacity on-line, levels of acetic acid were estimated by a software sensor using pH signal in a fermentation process of E.coli growing in a minimal medium. The measured values of acetic acid showed correlation to those of estimated by the software sensor. Lacitic acid production was also successfully estimated by the values of buffer capacities measured on-line.

• Food Science and Biotechnology
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• v.18 no.5
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• pp.1083-1090
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• 2009

Fermentation of wort was investigated with an ultimate goal to develop a fermented beverage rich in prebiotics and functional ingredients as well as desirable in flavors. Wort was fermented with Leuconostoc citreum HJ-P4 originated from kimchi and subjected to sensory descriptive analysis. L. citreum HJ-P4 produced various organic acids (e.g., lactic acid, acetic acid) as well as functional sugars (e.g., mannitol, panose) during wort fermentation. The concentration and ratio of lactic acid and acetic acid were significantly influenced by roasting conditions of malts used for wort preparation and aeration conditions during fermentation. The concentration of mannitol and panose varied depending on the sucrose content of wort and aeration conditions. Sensory characteristics of the fermented worts were clearly differentiated according to the roasting conditions of malts used for wort preparation and aeration conditions during fermentation. These results indicate that metabolite concentration of fermented wort and its sensory properties can be manipulated with roasting conditions of malts and fermentation conditions.

• Food Science and Preservation
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• v.30 no.4
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• pp.703-715
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• 2023

This study was conducted to investigate the fermentation characteristics and anti-obesity effects of acetic acid fermentation products of coffee wine. The live cell counts, soluble solids, pH and total acidity of the acetic acid unfermented coffee wine (AUFCW; day 0, before fermentation) were 6.35 log CFU/mL, 8.10 °Brix, 3.88, and 1.29%, respectively, while the acetic acid fermented coffee wine (AFCW; day 15, after fermentation) were 4.40 log CFU/mL, 8.57 °Brix, 3.07, and 7.45%, respectively. Pancreatic lipase inhibitory activity tended to increase as the acetic acid fermentation period increased. The anti-obesity effects of AFCW on 3T3-L1 cells, which was induced by MDI, were evaluated based on the lipid accumulation rate, leptin expression, and fat production-related gene expression (PPAR-γ and SREBP-1c) at the mRNA level. In the case of AFCW, the lipid accumulation rate and leptin expression were decreased to 69.37% and 50.20% at a concentration of 200 ㎍/mL, respectively, and the expression levels of PPAR-γ and SREBP-1c at the mRNA level were decreased to 79.89% and 48.81%, respectively. These results indicate that anti-obesity effect of acetic acid fermentation products could be increased by acetic acid fermentation of coffee wine.

• Korean Journal of Food Science and Technology
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• v.29 no.4
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• pp.745-751
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• 1997

Volatile flavor components of kochujang made from a glutinuous rice by traditional method were analyzed by using purge and trap method during fermentation, and identified with GC-MSD. Fifty-one volatile components including 19 alcohols, 13 esters, 7 acids, 3 aldehydes, 1 alkanes, 2 ketones, 2 amines, 1 benzene, 1 alkene, 1 phenol and others were found in kochujang made by traditional method. The number of volatile components detected immediately after making kochujang were 22 and increased to 41 components after 30 day of fermentation. The most number 51 of volatile components were found after 120 day of fermentation. Twenty-two volatile components were commonly found through the fermentation period such as acetic acid ethyl ester, ethanol, butanoic acid ethyl ester, 1-butanol, 2-methyl-1-propanol, 3-methyl-1-butanol, butanoic acid and ethenone. Peak area(%) of 1-butanol was the highest one among the volatile components at immediately after mashing while ethanol showed the highest peak area after 30 day of fermentation. Although the various types of peak areas of volatile components were shown in kochujang during the fermentation days, acetic acid-ethyl ester, ethanol, butanoic acid-ethyl ester, 1-butanol, 3-methyl-1-butanol and 2-methyl-1-propanol were mainly detected during fermentation. Those might be the major volatile components in kochujang made by traditional method.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.2
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• pp.535-542
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• 2019

The purpose of this study was to obtain basic data necessary for making a nuruk salt by comparing and analyzing the ingredients of various nuruk salts, and to select a nuruk salt that meets the users' needs. We selected the types of nuruk as the ihwaguk, miinguk, baekguk, and koji to identify the characteristics of the nuruk, and then analyzed the chemical characteristics after manufacturing the nuruk salts under the same conditions of fermentation, such as material ratio and temperature. In the manufacture of nuruk salt, the pH level dropped from 6.2~6.5 before fermentation to 6.1~6.2 three days after fermentation. The Acidity increased from 0.16~0.18 before fermentation to 0.22~0.25 after fermentation and there was no difference between the nuruk. The sugar content has risen since fermentation, and nuruk salt made by koji showed the largest increase in the sugar content. The salinity of the nuruk salt was raised to 37~44 after fermentation from 30~32 before fermentation and indicated largest increase in nuruk salt made by koji. Organic acids of nuruk salt were detected in the order of acetic acid, oxalic acid, malic acid, lactic acid, and citric acid. The oxalic acid of the baekguk salt was found to be 0.77 mg/mL, 2.3 times more of the koji, and the succinic acid was also found to be the highest with 1.19 mg/mL. Malic acid, lactic acid, acetic acid, and citric acid were found to have the highest amount of koji salt at 0.29 mg/mL, 1.48 mg/mL, and 0.12mg/mL, respectively, making it a better taste to be soft than other nuruk salt.