• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.9
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• pp.1366-1372
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• 2010

This study investigated the quality characteristics of brown rice vinegar (agitated culture and static culture) derived from brown rice Takju with different types of yeasts. The alcohol content by yeast was the highest in B (brown rice Takju produced by S. cerevisiae GRJ) at 14.3% and the titratable acidity was less than 0.6% in all ranges. When quality characteristics of agitated and static culture brown rice vinegar using them were compared, acidity of agitated culture vinegar recorded the highest level or 6.05% at 7 day of fermentation DV (brown rice vinegar produced by S. kluyveri DJ97) with the initial acidity of 1.0% and the initial pH of 3.9~4.0, and AV (brown rice vinegar produced by S. cerevisiae JK99), CV (brown rice vinegar produced by S. cerevisiae H9) and BV (brown rice vinegar produced by S. cerevisiae GRJ) recorded as 5.64, 5.55 and 5.32%, respectively. In addition, acidity of static culture vinegar increased continuously to 5.01~5.31% until the 14 day of fermentation and then tended to decrease slightly from the 16 day of fermentation. Difference in acidity and pH of brown rice vinegar according to types of yeast was not significant. Comparison of free amino acid of brown rice vinegar showed that for agitated culture brown rice vinegar, the content of total free amino acid was higher in the order of BV, DV, AV and CV and the content of essential amino acid was the highest in BV by recording over 1,000 ppm. The content of total free amino acid of static culture brown rice vinegar was higher than that of agitated culture vinegar in all ranges and especially static culture brown rice vinegar contained more serine, alanine, valine, isoleucine, leucine and $\gamma$-aminobutyric acid than agitated culture vinegar. In particular, $\gamma$-aminobutyric acid recorded over ten times higher level or 456.91~522.66 ppm. From these results, quality characteristics of brown rice vinegar was affected by acetic acid fermentation methods rather than types of yeast. However, as future aging process is expected to change flavor components and sensory characteristics, studies on various quality factors of vinegar are needed.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.6
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• pp.529-536
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• 1986

By modified method yellow corvenia(called $Y_3$) was prepared with $4\%$ salt, $4\%$ KCl, $6\%$ sorbitol, $0.5\%$ lactic acid and $4\%$ alcohol extract of red pepper to improve the quality of fermented sea food. In this study, changes of volatile compounds and fatty acid composition obtained from modified fermented yellow corvenia($Y_3$) were experimented during fermentation, comparing with conventional fermented yellow corvenia(called $Y_1,\;20\%$ of salt contents). Total lipid of yellow corvenia was composed of $78.1\%$ of neutral lipid, $21.2\%$ of phospholipid and $0.7\%$ of glycolipid. And monoeonoic acid was held $37.4\%$ of fatty acid composition of total lipid and saturated fatty acid ($34.8\%$), polyenoic acid ($27.7\%$) were followed. Saturated fatty acid($C_{14:0},\;C_{16:0},\;C_{18:0}$) in $Y_1,\;Y_3$ increased, polyenoic acid ($C_{22:6}\;C_{22:5}\;C_{20:5}$) decreased while monoenoic acid($C_{16:1}\;C_{18:1}$) in those was little fluctuated during fermentation. Thirty-three kinds of volatile component in whole volatile compounds obtained from $Y_1,\;Y_3$ at 90 days fermentation were identified, and composed of some hydrocarbons (8 kinds), alcohols (7 kinds), acids (6 kinds), aldehydes(4 kinds), sulfides(2 kinds), ketones (2 kinds), one of phenol and 3 kinds of the other components. Among the whole volatile compounds 2-ethoxy ethanol and was held $79.35\%$ in $Y_3$, whereas nonadecane was held $75.85\%$ in $Y_1$. During fermentation 8 kinds of volatile acids, 5 kinds of amines and 9 kinds of carbonyl compounds were also detected. Those volatile acid such as acetic acid, isovaleric acid, n-caproic acid, n-butyric acid were the major portion of total volatile acids in $Y_3$ at 90 days fermentation. Meanwhile, carbonyl compounds such as ethanal, 2-butanone and butanal were the major ones, while TMA held the most part of volatile amines in $Y_3$ during fermentation. From the result of sniff test, the components which are believed to contribute to the characteristic flavor of fermented product $Y_1,\;Y_3$ are deduced to be volatile acid, carbonyl compounds and amines in order. Conclusively, there was little difference in composition of volatile components, but merely a little difference in content of those between $Y_3$ and $Y_1$.

• Korean Journal of Environmental Agriculture
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• v.23 no.4
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• pp.220-227
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• 2004

This study showed that thermophilic anaerobic acid fermentation of food wastes had an enhanced hydrolysis capability and improvement of acidification efficiency. Influence of pH on the anaerobic hydrolysis and acidogenesis was investigated to determine the proper alkalinity in the thermophilic fermentation of food wastes. The results of putting NaOH as alkali to evaluate hydrolysis and acid fermentation efficiency In acid fermentation process of food wastes showed that the food wastes pretreated with 0.05 g NaOH/g TS had the maximum 12,600 mg/L of VFAs concentration during HRT 3 days in $55^{\circ}C$ thermophilic condition and the maximum 9,700 mg/L of VFAs concentration during HRT 5 days in $35^{\circ}C$ mesophilic condition. The accomplishment of high VFAs concentration resulted from that the main component of food wastes such as cellulose, lignin and etc. is performed active chemical decomposition by alkali in thermophilic condition. The major components of VFAs produced from the thermophilic acid fermentation process of food wastes were the short chain fatty acids such as acetic acid, butyric acid, and propionic acid.

• Korean Journal of Agricultural Science
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• v.7 no.2
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• pp.169-175
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• 1980

These studies were conducted to induce the available mutant strains in acetic acid bacteria by the irradiation of UV-light and the treatment of N-methyl-N'-nitro-N'-nitrosoguanidine. 109 strains which were capable of producing acid in the ethanol containing medium were isolated from vinegar and Kimchi collected from the region of Daejeon city. From the collection T-50 strain was identified to have a strong fermentation power and selected as a mother strain for the study. Two mutants were obtained by treating T-50 strain with UV and NTG, and these mutants had a rapid acid production in the initial stage. The study was then made to compare the basic condition for acetic acid production of the mother strain and two mutant strains. The summarized results were as follows; 1. The isolated strain (T-50) was identified as Acetobacter aceti by Bergey's manual and Acetic acid bacteria (Tokyo Univ. press). 2. The selected strain was died completely when the strain was irradiated with 15 W UV-light at a distance of 45 cm for 160 seconds. 3. The mutants such as U-48 and N-67 were rapid in the acetic acid production at the initial stage compare to the mother strain. 4. Acetic acid formation by the shaking culture method was maximized in 2 days culture, and the optimal temperature for acetic acid production was $30^{\circ}C$. 5. Acetic acid was effectively produced by the addition of 0.1% ammonium sulfate as a nitrogen source and was also produced rapidly by the addition of 0.1% glucose.

• Applied Biological Chemistry
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• v.45 no.1
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• pp.11-17
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• 2002

Fermentation characteristics with/without nitrogen source and quality of the fruit distillate of Opuntia ficus-indica var. saboten were investigated during the manufacturing process of a Korean traditional liquor. As the fermentation period increased, acidity, brix degree, and alcohol concentration increased, whereas pH and contents of reducing sugar decreased. Acidity, pH, and brix degree were higher, whereas the content of reducing sugar lower, in the nitrogen source-added distillate than in the distillate without nitrogen source. The growth of yeast increased, while that of bacteria decreased; this trend was more prominent with the addition of a nitrogen source. Sojues, distilled from two types of mashes and diluted with $H_2O$ and tails of distillate into 22% alcohol concentration, showed pH $3.7{\sim}4.0$, acidity $0.02{\sim}0.10$, and $5.4{\sim}6.1$ $^{\circ}Brix$. Analysis through GC using direct injection methods revealed common volatile flavor compounds in sojues, including acetaldehyde, acetyl acetone, acetic acid ethyl ester, ethyl alcohol, 2-propyl alcohol, acetone, n-propyl alcohol, butanoic acid methyl ester, 2-phenyl ethanol, thymol, acetic acid phenyl ester, and vanillic aldehyde. As revealed through the sensory evaluation, no significant difference (p>0.05) in overall acceptability was shown among four experimental groups, while color and flavor showed significant differences(p<0.05).

• Korean journal of food and cookery science
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• v.20 no.5
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• pp.436-443
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• 2004

The purpose of this study was to examine the physico-chemical and sensory characteristics of Kakdugi made with mashed red pepper. With regard to the pH of the Kakdugi, those of the juice from Kakdugi with red pepper powder and of the liquid with mashed red pepper were the highest and lowest immediately after preparation, respectively, but thereafter both slightly decreased, but were similar after the fifth week. Generally, the total acidity of Kakdugi liquid was the higher than that of Kakdugi juice. With regard to the L value, that of the Kakdugi juice was higher than that of Kakdugi liquid and that of Kakdugi with mashed red pepper washigher than that of Kakdugi with red pepper powder. From the third week, the 'L' values of all samples generally decreased. The 'a' value of the Kakdugi liquid with mashed red pepper during fermentation was highest During early fermentation, the juice of Kakdugi with red pepper powder showed a higher value than that of Kakdugi with mashed red pepper, but conversely, from the second week that of Kakdugi with mashed red pepper was higher than that of Kakdugi with red pepper powder. The 'b' value of the juice from Kakdugi with red pepper powder was highest until the second week, but from the third week that of Kakdugi with mashed red pepper was highest. With respect to the organic acids contents, those of citric, quinic and malic acids decreased, but those of lactic and acetic acids increased during fermentation progression. In addition, the citric, lacticand malic acids contents of the Kakdugi with mashed red pepper werethe highest, whereas that of quinic acid of the Kakdugi with red pepper powder was the highest. From the forth week, the acetic acid content of the Kakdugi with mashed red pepper was further increased. As a result of the sensory test, Kakdugi with mashed red pepper showed significantly higher values with regard to redness and fresh flavor, but in overall acceptability in the QDA, appearance and taste in the acceptance test. Therefore, our results indicate that mashed red pepper particularly increased the 'a' value and organic acid contents of Kakdugi compared to those of red pepper powder, leading to an increased overall acceptability.

• Korean Journal of Organic Agriculture
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• v.21 no.4
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• pp.629-646
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• 2013

This study was conducted to investigate effects of terpenoids-rich plant extracts (TRPE) on the in vitro ruminal fermentation characteristics and methane production. The ruminal fluid was collected from a cannulated Hanwoo cow fed concentrate and timothy in the ratio of 6 to 4. The TRPE as Mint (Mentha arvensis var. piperascens), Pine (Pinus densiflora), Japan cedar (Cryptomeria japonica), Sichuan pepper (Zanthoxylum piperitum), Hinoki cypress (Chamaecyparis obtuse) and Japanese black pine (Pinus thunbergii) were used in this study. The 15 mL of mixture, contains McDougall buffer and rumen fluid in the ratio of 2 to 1. The mixture was dispensed anaerobically 50 mL serum bottles and it is contained 0.3 g timothy substrate and 5% TRPE. The bottles were incubated at $39^{\circ}C$ for 3, 6, 9, 12, 24, 48 and 72 hours. The pH value decrease by increased incubation times and the pH values at all times were significantly (p<0.05) higher in treatments than in control. The digestibility of dry matter at 3 hours was significantly (p<0.05) higher in mint treatment than in control. Productions of total gas and carbon dioxide at before 12 hours was significantly lower (p<0.05) in treatments than in control. The methane production at 24 hours was significantly (p<0.05) lower in treatments than in control. The concentrations of acetic acid and propionic acid at 24 hours were significantly higher (p<0.05) in mint and pine treatments than in control. In conclusion, the terpenoid-rich plant extracts were shown to decreased methane emission and without adversely affected ruminal fermentation. Therefore, the terpenoid-rich plant extracts as mint and pine were shown to decreased methane production and it has potential possibility for ruminal fermentations.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.5
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• pp.459-468
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• 1986

This study was attempted to process low-sodium salt fermented small shrimp as substitutes for traditional high-sodium salt fermented one which has widely been favored and consumed in Korea. Low-salt fermented small shrimp was prepared with $4\%$ sodium chloride and $4\%$ potassium chloride, and various additives such as $0.5\%$ lactic acid, $6\%$ sorbitol and $4\%$ ethylalcohol extract of red pepper as preservatives and flavor enhancers. And the changes of taste compounds, volatile compounds and fatty acid composition in low-salt fermented small shrimp were analyzed and compared with those of conventional $20\%$ sodium salt fermented one during the fermentation of 120 days at $25{\pm}3^{\circ}C$. The most favorable taste for fermented small shrimp were reached at 60 days of fermentation. Judging from sensory evaluation, little difference of taste was detected between the low-salt fermented small shrimp and high-sodium salt fermented one. The principal taste compounds in fermented small shrimp were free amino acids, and betaine and nucleotides and their related compounds played an assistant role. The major amino acids in fermented small shrimp were glutamic acid, leucine, proline, glycine, lysine and aspartic acid. The major fatty acids in fermented small shrimp samples were 16:0, 20:5, 22:6, 16:1 and 18:1, and unsaturated fatty acids decreased slightly while saturated fatty acids increased during fermentation. At 60 days of fermentation 8 kinds of volatile fatty acids (acetic acid, propionic acid, isobutyric acid, butyric acid, isovaleric acid, valeric acid, isocarproic acid, carproic acid), 6 kinds of carbonyl compounds (ethanal, propanal, 2-methylpropanal, 3-methylbutanal, pentanal, 2-methylpentanal), and 3 kinds of volatile amines (methylamine, trimethylamine, isopropylamine) were identified.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.7
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• pp.927-935
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• 2012

This study was performed to develop functional vinegar by using cucumbers through two stages of fermentation. The alcohol content was maximized (7.8%) after 6-days of alcohol fermentation at $25^{\circ}C$ by adjusting the initial sugar concentration to $15^{\circ}Brix$, and vinegar with an acidity of 5.8% was obtained after 12-days of acetic acid fermentation at $30^{\circ}C$. The major sugars in the produced vinegar were glucose and fructose, which were present in concentrations of 3,067.26 and 395.73 mg%, respectively. The major organic acids were acetic acid and succinic acid, which were present in concentrations of 4,410.5 and 841.11 mg%, respectively. The total free amino acid content of the cucumber vinegar was 181.45 ${\mu}g/mL$ and citrulline, valine, aspartic acid, asparagine, and ornithine were the major amino acids. The inorganic components included various alkaline elements, such as K, Ca, and Mg. In addition, experimental methods to assess the DPPH and $ABTS^+$ radical-scavenging ability, reducing power, and ${\beta}$-carotene bleaching activity showed that the cucumber vinegar had strong antioxidant properties. The total polyphenol content, which are the major components responsible for the antioxidant activities of the cucumber vinegar, was 40.14 mg/100 mL. The cucumber vinegar showed significantly higher hepatic aldehyde dehydrogenase activity when compared to the alcoholic control (negative) and the marketing drink (positive), resulting in decreased plasma acetaldehyde concentrations in rats. These results demonstrate that cucumber vinegar possesses antioxidant properties and holds great promise for use in preventing hangovers.

• Journal of Life Science
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• v.29 no.3
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• pp.345-353
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• 2019

This study investigated the physiochemical properties, the anti-oxidant and alcohol metabolism enzyme activities, and the anti-inflammatory effects of three muskmelon vinegars prepared under different fermentation conditions, namely MV-1, MV-2, and MV-3. The total acidity of each vinegar was 4.00%, 4.32%, and 4.35%, respectively. Organic acid analysis showed that malic acid (58.37 mg/ml) was the most prevalent in MV-1 and that acetic acid was most prevalent in both MV-2 (46.95 mg/ml) and MV-3 (66.70 mg/ml). The total phenolic content of the muskmelon vinegars was highest at $129.74{\mu}g$ tannic acid equivalents (TAE)/ml in MV-3. The DPPH radical scavenging activity of the vinegars increased in a dose-dependent manner (p<0.05) and was 89.28% at MV-3 40% concentration. Similarly, SOD activitity increased in a concentration-dependent manner (p<0.05) so that levels for MV-1, MV-2, and MV-3 at 60% concentrations were 40.84%, 52.17% and 72.55%, respectively (p<0.05). Moreover, the ADH and ALDH activities of muskmelon vinegar were seen to increase in a concentration-dependent manner; ADH activity at 60% concentration was highest at 136.58% in MV-1 and ALDH activity at 60% concentration was highest at 100.25% in MV-2. The nitrite scavenging activities of MV-1, MV-2, and MV-3 at pH 1.2 were found to be 81.58%, 94.72%, and 87.75%, respectively. Anti-inflammatory effects were also examined, using LPS-stimulated RAW 264.7 cells, and nitric oxide production was reduced to 25.93%, 10.01%, and 79.75% by addition of MV-1, MV-2, and MV-3 at 1% concentration, respectively (p<0.05). These results suggest that the MV-3 muskmelon vinegar has great potential as an ingredient for high quality functional health beverages.