• Korean Journal of Food Science and Technology
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• v.14 no.1
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• pp.6-10
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• 1982

To investigate the effect of organic acids on suppression of fishy odor, the change of the odor and the remaining amount of trimethyamine (TMA), selected as the representative component of fishy odor in clam pickle (15.5% NaCl) were examined by sensory evaluation and gas chromatography. The fishy odor linearly decreased as the amount of vinegar increased at ${\alpha}=0.01$, but there was no significant difference of fishness score for the changes of storage period and kinds of acid. Overall acceptability score was found to be the best when 8 ml vinegar added to 100g clam pickle. The remaining amount of TMA showed the tendency to decrease as the amount of acetic acid and storage time increased and kinds of acid were changed in order of acetic, malic and citric acid. However when $4\;{\mu}l/ml$ acetic acid (=8 ml vinegar/100g clam pickle) was added, the percentage of the remaining amount of TMA showed little decrease from about 95% for 72 hours of storage time. From the results of sensory evaluation and gas chromatography, it was considered that acids have the effect on suppression of fishy odor by producing non-volatile salts by combining with TMA chemically and that the effect of acids on suppression of fishy odor is mainly due to the masking effect at the concentration commonly used.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.7
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• pp.1016-1027
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• 2015

This study collected 120 figs, classified them into six degrees of maturity according to hardness values, and analyzed contents of organic acids and free sugars. Volatile compounds in figs were investigated using the solid-phase microextraction method of gas chromatography/mass spectrometry. For measurement of texture, elasticity increased up to stage 4 and decreased again. Cohesiveness and brittleness increased with maturation. Organic acids in figs were mainly composed of citric acid, malic acid, and tartaric acid in the final stage. Fructose and glucose were the major sugar components of figs. Fructose content decreased from stage 1 to stage 4 and then increased significantly. One hundred and nineteen volatile compounds were identified in figs, and classes were 14 acids, 15 alcohols, 23 aldehydes, 10 esters, 33 hydrocarbons, 11 ketones, four aromatics, six miscellaneous, and five terpenes. The dominant volatile components in figs were hexadecanoic acid, hexane, dodecanal, DL-limonene, 2-hexanal, nonanal, and 6-methyl-5-hepten-2-one.

• Applied Biological Chemistry
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• v.9
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• pp.9-27
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• 1968

Studies were carried out in order to elucidate chemical components and microflora in three types of soy-sauce, 12-year aged soy-sauce prepared by improved method. 7-year aged and 20-year aged soy-sauce prepared by ordinary method. They results are summarized as follows: 1. The followings are found to be the important factors affecting the quality of soy sauce. a. Organic acids, reducing sugars and free amino acids were increased in the course of storage. b. In the aged soy-sauces under study non-volatile organic acid increased while volatile organic acid decreased and the total acidity was dependent only upon tie latter. c. It was found that suit concentration decreased during the storage. 2. The results of investigation of microflora in the stored soy-sauce are shown as follows. Soy-sauce Improved Ordinary Microbe 12-Y. 20-Y. 7-Y. Aerobic bacteria colony/1ml. 6 123 2 Halophilic lactic acid bacteria colony/1ml. 4 6 10 Osmophilic yeast colony/1ml. $828{\times}10^4$ 248 - b. In the stored soy-sauces, aerobic bacteria are incapable of growing due to drop in pH value and the influence of salt concentration. c. Halophilic lactic acid bacteria are incapable of growing due to drop in pH value, even the salt concentrations decreased during the storage. d. Osmophilic yeast are still growing in low pH value and in the decreasing salt concentration during the strage. 3. The results of amino acid analysis by paper partition chromatographic and calorimetric methods are shown as follows. a. Fourteen kinds of amino acid and thirteen amino acids were detected in the soy-sauce of 12-year aged improved soy-sauce and 7-year aged and 20-year aged ordinary one, respectively. b. The contents of aspartic acid, glutamic acid, serine, valine, leucine, lysine, histidine and methionine increased in the 20-year aged ordinary soy-sauce compared to the 7-year aged one. On the other hand those of alanine, tyrosine, phenylalanine and cystine decreased. 4. The results of sugar analysis by paper chromatography are as follows. a. In the 12-year aged improved soy-sauce, galactose, glucose, arabinose, xylose, rhamnose, maltose and an unknown were detected, and their amounts were in the above order except maltose and an unknown. b. Both in the 7 and 12-year aged ordinary soy-sauces, galactose, arabinose, xylose, glucose and rhamnose were detected and the amounts of the sugars were in the above order. c. In the non-aged ordinary soy-sauce, glucose was not detected but detected from 7-year and 20-year aged ordinary soy-sauce. 5. The results of organic acid analysis by paper chromatography were as follows. a. As volatile acids, acetic, propionic and butyric acids were detected in the 7-year aged ordinary soy-sauce. On the other hand in both the 20-year aged ordinary soy-sauce and the 12-year aged improved ones, only acetic acid was abundant while propionic and butyric acids were round in trace. It was found that propionic and butyric acids, as the unpleasant flavor components, decreased during the storage. b. In the ordinary soy-sauce, citric acid were produced during the storage and lack, malic and tartaric acids increased in the course of aging while succinic, glycolic, fumaric and malonic acids were shown to decrease. Glutaric and oxalic acids disappeared. Citric acid was produced also in the improved soy-sauce, but lactic, tartaric, succinic, malic, and glycolic acids decreased, while both malonic and glutaric acids disappeared. From the above results the citric acid production was considered to be a favorable factor for the taste. c. In the aged soy-sauces, pyruvic, α-ketoglutaric and probably acetoacetic and oxaloacetic acids (both in trace) were present and their amounts were in the above order. All of the α-keto acid abruptly decreased during the storage.

• Food Science and Biotechnology
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• v.15 no.5
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• pp.688-693
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• 2006

Glucosinolates are hydrolyzed by the enzyme myrosinase and are mainly found in cruciferous vegetables such as Chinese cabbage (Brassica campestris L. ssp. pekinensis). lsothiocyanates (ITCs) are glucosinolate degradation products with reported anticarcinogenic properties. Korean Chinese cabbage in the form of 'kimchi' is a staple part of the Korean diet. In this study, we examined the effects of storage temperature and duration on glucosinolate, ITC, soluble sugar, and organic acid levels in kimchi. Changes in pH and the impact of various parts of the Korean Chinese cabbage being used during the preparation of the dish were also assessed. Extracted ITC levels, analyzed via gas chromatography (GC) and GC/mass spectrometry (GC/MS), were higher in the midrib parts than in the cabbage leaves after storage at both 4 and $20^{\circ}C$. During storage, organic acid levels increased while soluble sugars were depleted. The pH initially increased (after 1 day at $20^{\circ}C$, and 1 week at $4^{\circ}C$), but subsequently decreased over time at both temperatures. Glucosinolate and ITC levels increased in the beginning of storage but then generally fell during further storage. Our data suggest that acidity-related reduction in myrosinase activity during storage may decrease glucosinolate and ITC levels. The changes in these levels depended on the storage conditions and the Korean Chinese cabbage parts used for the kimchi preparation.

• Korean Journal of Organic Agriculture
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• v.22 no.4
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• pp.825-839
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• 2014

Antioxidant activity is important for reducing oxidative stress that causes various metabolic disorders. Metabolic disorders are highly related to loss of productivity in livestock. Therefore, development of effective antioxidant compounds originating from plants is important for organic agriculture. Phenolic compounds in edible plants are regarded as major components relevant to antioxidant activity. The present study investigated the changes in antioxidant activity and phenolic compound profiles of Aronia (Aronia meloncarpa) by fermentation using different strains of Leuconostoc mesenteroides. A total of 5 strains of L. mesenteroides were used as starter cultures and their ${\beta}$-glucosidase activities were measured. A total of 6 experiment runs were prepared, one for control (uninoculated) and the others (inoculated) for treatments. For biological activity, antioxidant and antibacterial activities were measured. For phenolic compound profiling, TLC and HPLC analysis were performed. The strains of KACC12313 and KACC12315 showed greater enzyme activity than others. Treatment with KCCM35046 showed strong and broad antibacterial activity against to Listeria monocytogenes. Treatments with KCCM35046 and KACC12315 showed the highest total polyphenol content. The highest antioxidant activity was found in KACC12315 treatment. No remarkable alteration was found in thin layer chromatography (TLC) analysis. In phenolic compound profiling analysis, KCCM35046 showed notable alteration in compound area ratio compared to others and also showed the highest caffeic acid content. In chlorogenic acid, treatments with KCCM35046 and KACC12315 showed great content than others. Treatment with KACC12315 showed the greatest content of trans-ferulic acid. As a result of relative performance indexing analysis, L. mesenteroides KCCM35046 and KACC12315 were selected as the best strain for the fermentation of Aronia.

• Korean Journal of Food Science and Technology
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• v.26 no.2
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• pp.162-166
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• 1994

A rapid gas chromatographic (GC) profiling method for the simultaneous analysis of volatile and nonvolatile organic acids was applied to alcoholic beverages (white wine, red wine, brandy, and beer). It involves the solid-phase extraction of organic acids using Chromosorb P as the sorbent and diethyl ether as the eluent with subsequent triethylamine treatment. The resulting triethylammonium salts of acids were directly converted to volatile tert.-butyldimethylsilyl derivatives, which were analyzed by dual-capillary column GC and GC-mass spectrometry. From the alcoholic beverages studied, more than 29 organic acids were detected. When the simplified retention infer (RI) spectra of organic acids, and the direct comparisor method between alcoholic beverages and a test sample were attempted to identify a test sample, it was quickly recognized to be a red wine with the 998 ppt match quality value.

• Journal of Mushroom
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• v.20 no.4
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• pp.187-192
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• 2022

Wolfiporia cocos is an edible fungus commercially cultivated in Asia. To investigate metabolic changes of W. cocos mycelia under both light and dark culture conditions, gas chromatography mass spectrometry (GC-MS) and high-performance liquid chromatography (HPLC) analyses were performed. In terms of the total amount of sugars, alcohols, amino acids, organic acids, fatty acids, and purines, there no significant differences between the W. cocos mycelia cultivated under light (L) or dark (D) conditions (p < 0.05). However, there were some differences with respect to the production of particular sugars and proteins. The levels of trehalose (L: 17.2 ± 0.3% vs. D: 13.9 ± 1.6%), maltose (L: 0.9 ± 0.1% vs. D: 0.3 ± 0.1%), turanose (L: 0.7 ± 0.2% vs. D: 0.1 ± 0.1%), glutamine (L: 1.6 ± 0.3% vs. D: 0.7 ± 0.2%), and proline (L: 0.3 ± 0% vs. D: 0.1 ± 0%) were all significantly higher under light condition (p < 0.05). In contrast, the levels of galactose (L: 13.7 ± 1.2% vs. D: 17.6 ± 2.0%), aspartic acid (L: 0.6 ± 0.1 % vs. D: 0.9 ± 0.1%), cystathionine (L: 0.6 ± 0.1% vs. D: 0.8 ± 0 %), and malic acid (L: 0.7 ± 0.1% vs. D: 1.2 ± 0.1%) were higher under the dark condition. It is worth noting that the amount of pachymic acid, a pharmaceutically active compound of W. cocos, was 1.68 times greater under the light condition (p < 0.05).

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.6
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• pp.477-483
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• 2006

Ionic liquids in the form of organic salts are being widely used as new solvent media. In this paper three positional isomers, o-amino benzoic acid, m-amino benzoic acid, and p-amino benzoic acids were separated with four different ionic liquids as mobile phase additives using high performance liquid chromatography (HPLC). The following ionic liquids were used: 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIm][$BF_{4}$]), 1-ethyl-3-methylimidazolium tetrafluoroborate ([EMIm][$BF_{4}$]), 1-ethyl-3-methylimidazolium methylsulfate ([EMIm][MS]), and 1-octyl-3-methylimidazolium methylsulfate ([OMIm][MS]). The effects of the alkyl group length on the imidazolium ring and its counterion, and the concentrations of the ionic liquids on the retention factors and resolutions of amino benzoic acid isomers were tested. The results of the separations with ionic liquids as the eluents were better than those without ionic liquids. Excellent separations of the three isomers were achieved using 2.0-8.0 mM/L [OMIm][MS] and 1.0-8.0 mM/L [EMIm][MS] as the eluent modifiers.

• Journal of the Korean Wood Science and Technology
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• v.28 no.4
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• pp.1-9
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• 2000

This experiment was accomplished to investigate antioxidative activity of Korean mistletoe by organic solvents partitioning of methanol extact of 3 Korean mistletoes, fractionationing on column chromatography, and evaluation the reduction of a free radical ${\alpha}$,${\alpha}$-diphenyl-${\beta}$-picrylhydrazyl. Butanol partition of Loranthus yadoriki MeOH extract showed higher electron donating ability than ${\alpha}$-tocopherol. It was thought phenolic compounds including gallic acid account for antioxidative activity, on execution sub-fractionation, electron donating ability evaluation, and GC/MS analysis, but further studies on what are major actives must be investigated exactly.

• Bulletin of the Korean Chemical Society
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• v.24 no.7
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• pp.911-915
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• 2003

Two liquid chromatographic chiral stationary phases (CSPs) based on (+)-(18-crown-6)-2,3,11,12-tetracarboxylic acid were successfully applied in the resolution of racemic tocainide and its analogues. In the resolution of tocainide, especially, the CSP containing N-CH₃ amide tethering groups was quite effective, showing clear baseline resolution (RS: 2.66) with reasonable enantioselectivity ( a: 1.25). Consequently, the CSP containing N-CH₃ amide tethering groups is expected to be useful to monitor the enantiomeric composition of tocainide in clinical samples. In addition, the chromatographic behaviors for the resolution of tocainide and its analogues on the two CSPs were found controllable by varying the content and the type of organic and acidic modifiers in aqueous mobile phase.