• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.2
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• pp.283-287
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• 2001

Persimmon vinegar was clarified with 400mg/L chitosans of two different molecular weights (MW 150 and 37 kDa), and its quality changes were investigated during storage at room temperature for 6 months. No significant changes in pH, acidity, and tannin content were observed. However, turbidity and browning slightly increased while protein content slightly decreased. Soluble solids content slightly decreased when treated with high MW chitosan. Color L* value decreased while a* and b* values increased with storage periods. The major organic acid in the persimmon vinegar after 6 months storage was acetic acid with minor lactic, malic, tartaric, galacturonic, and succinic acids. Overall, the quality of persimmon vinegar clarified by chitosan treatment, irrespective of molecular weight, was more stable without noticeable changes during storage than that of control group without chitosan treatment.

• Korean Journal of Microbiology
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• v.6 no.3
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• pp.81-86
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• 1968

1. Amylolytic enzyme activities of Asp. oryzae and Asp. oryzae var. fulvus using the glucose as the carbon sources increased remarkably according to the decrease of the residual sugars. 2. The amylase productions of Asp. oryzae and Asp. oryzae var. fulvus were increased and enhanced when the organisms lave belen cultured in modified Koji media containing maltose as adaptive substrate. However, being devoid of maltose the level of amylase activities were lower and the begining of the production was prolonged. 3. The effects of C-sources on the amylase production of them were observed. The level of amylase activity varied with C-sources and their concentrations Marked increase of amylase production was afforded by starch and maltose. The effects of citric acid and tartaric acid were little or nothing. 4. Using the sucrose and lactose as the adaptive substrates both strains show the maximum amylolytic enzyme activities at the 3% concentrations of those sugars.

• Applied Biological Chemistry
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• v.17 no.1
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• pp.63-80
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• 1974

The chemical components of Citrus junos produced in Korea were divided into two parts; common and special components respectively. In the former the relation between the physiological effects of the plant and its ripening process was observed periodically while the latter was analyzed the ripening fruits for their effective utilization as food. The results are summarized as follows: 1. The analytical result of seasonal change showed that the rind ratio was higher than the flesh ratio and on a regional basis, the rind ratio was higher in the islands than on land areas. 2. In the experiment the moisture was increased until the third period, but afterwards it was made constant. While the content of crude fat, cellulose, ash, total acid and soluble non-nitrogen material were decreased until the third period and the cotent of cellulose and total acid were continuousely redused until the last period. In con trast with the above the content of reducing sugars was increased but the content of crude fat, cellulose, ash, crude protein and soluble non-nitrogen material were increased until last period. 3. The content of vitamin C was richer in the rind than in the flesh, in the Korean species than in the Japanese. 4. Free sugars; xylose, fructose, glucose were richer in the rind than in the flesh. 5. The content of volatile organic acids was richer in the rind than in the flesh. Among them, volatile acids, acetic acid, formic and n-valeric acid were found in the rind and formic acid, acetic acid and propionic acid were deteceed in the flesh. 6. The total content of non-volatile acids was richer in the flesh than in the rind. In the kind of non-volatile acids, citric acid,glutaric acid, malic acid, tartaric acid, oxalic acid, malonic acid, succinic acid and an unknown acid were found in the rind and citric acid, malic acid, succinic acid, oxalic acid, glutaric acid and malonic acid in the flesh. 7. Three kinds of aromatic components: D-limonene, ${\alpha}-pinene$, p-cymene and seven other kinds of unknown aromatic components were detected in neutral essential oils. Among them, D-limonene seemed to be main aromatic component in the fruits. 8. From the above results it is confirmed that both rind and flesh of the ripened fruit could be utilized for food effectively, and unripened fruits are suitable for producing citric acid, ripened fruits are also useful for producing juice.

• Food Science and Preservation
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• v.15 no.6
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• pp.864-871
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• 2008

The chemical components and physiological activities of Neungee mushroom (Sarcodon aspratus) were investigated to assess its nutritional and functional value. The moisture, total protein, crude fat and ash contents of Neungee mushroom were 85.73%, 1.78%, 1.87% and 1.27%, respectively. The alanine, linoleic acid, tartaric acid and glucose concentrations in Neungee mushrooms were 90.11, 39.09, 75.47 and 1,680 mg%, respectively. The radical and nitrate scavenging activities in Neungee mushroom extracts were 46.2% and 77.8% on $800{\mu}g/mL$ depending on the extract concentration. The lipid peroxidation inhibitory effect of Neungee mushroom extract ($1,500\;{\mu}g/mL$) was $2,347\;{\mu}mol$ MDA/g liver. We also observed that an extract concentration of $1,500\;{\mu}g/mL$ was more effective than the control at 7 d. The cytotoxicity of the Neungee mushroom extract ($100\;{\mu}g/mL$) for the A549 (lung carcinoma) cells was 96.0%.

• Food Science and Preservation
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• v.12 no.4
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• pp.336-343
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• 2005

This study was conducted to investigate the quality characteristics of candy products added with hot-water extract of korean mountain ginsengs as the useful food materials. Water content of the products were $0.41{\sim}0.88\%$. Candy product with $5\%$ addition showed the highest content($87.5\%$) in Brix. pH ranges of the products were $5.50{\sim}5.56$. In terms of Hunters color value, L value was lower in $10\%$ candy product(56.40) than that of other products, while a and b value were increased in $10\%$ candy product. Sucrose was the major free sugar of candy products, and major organic acids were malic, tartaric and citric acid. Free amino acids were predominantly arginine, serine, aspartic acid and proline. The major minerals were K, Mn, Na and Mg. Antioxidant activity of candy products were about $64.28{\sim}70.88\%$ compared to $96.81\%$ of BHA(200 ppm). Result of sensory evaluation of $10\%$ candy products gained higher sensory score in overall acceptance, compared to the other products.

• Food Science and Preservation
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• v.18 no.1
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• pp.53-58
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• 2011

Activity-guided isolation from an ethylacetate-soluble fraction of a 70% (v/v) ethanolic extract from the roots of Taraxacum ohwianum, using a pancreatic lipase inhibition assay, resulted in isolation and identification of five phenolic metabolites of previously known structure; these were 3,5-di-O-caffeoylquinic acid, chicoric acid, caffeic acid, protocatechuic aldehyde, and luteolin. All structures were confirmed by NMR and MS scpectroscopic data. Of these compounds 3,5-di-O-caffeoylquinic acid exhibited the most potent inhibitory activity, with $IC_{50}$ of $65.1{\pm}0.7\;{\mu}M$ against pancreatic lipase.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.11
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• pp.1685-1690
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• 2016

Xanthine oxidase (XO) inhibitors play an important role in the treatment of gout and many other diseases related to superoxide anion metabolism. In this study, four commercial fruit juices and three vinegars were evaluated for their inhibitory activity of XO (XOI), as well as contents of organic acids by HPLC with UV detection. Five different organic acids were detected in commercial samples: acetic acid and malic acid were the most prominent in vinegars and fruit juices, respectively. The vinegars showed high XOI activity (33.8~64.9%) related to the great concentration of acetic acid ($R^2=0.7192$). The presence of acetic acid in vinegar could be responsible for its XOI effect.

• Resources Recycling
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• v.28 no.6
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• pp.36-45
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• 2019

The spent petroleum catalysts contain rare metals such as vanadium, nickel, molybdenum, and cobalt. Therefore, the leaching of these rare metals from spent petroleum catalysts by organic acid was investigated in the present study. The leaching efficiency of metals by organic acid was in the following order: oxalic acid > tartaric acid > citric acid > maleic acid > ascorbic acid. Among the organic acids employed in this work, oxalic acid can be considered to be superior to the other acids in terms of metals leaching efficiency. The effect of several leaching conditions such as temperature, acid concentration, pulp density, stirring speed, and reaction time on the leaching of metals was investigated. Vanadium and molybdenum were selectively dissolved by oxalic acid from the spent catalysts. The leaching kinetics of vanadium by oxalic acid was also investigated. An activation energy of 8.76 kJ/mol indicated that the leaching kinetics of vanadium by oxalic acid solution was controlled by mass transfer.

• Korean Journal of Human Ecology
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• v.8 no.4
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• pp.23-35
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• 2005

The purpose of this study was to analyze the chemical components of Perilla leaf(frutescens Britton var. scuta Kudo) according to the making process, and to examine Hunter's color value and sensory evaluation of Jasosuksu by extraction time. Perilla leaves were prepared in three types; fresh leaf, dried leaf in the shade and roasted leaf after being dried in the shade in order to make Jasosuksu. The results of the research were as follows: Free sugars(sucrose, glucose, fructose) and organic acids(citric acid, tartaric acid, malic acid, succinic acid) were present in the fresh leaf, dried leaf and roasted leaf. $15{\sim}16$ kinds of amino acid including aspartic acid were determined in the fresh leaf, dried leaf and roasted leaf, and the major free amino acids were serine, aspartic acid, and glutamic acid. The major total amino acids of tile fresh leaf, dried leaf and roasted leaf were glutamic acid, histinine, and glycine. The major fatty acids of Perilla leaves were palmitic acid, linolenic acid, and linolenic acid. The content ratio of linolenic acid in fresh leaves was the highest, but that of palmitic acid was lower than that of dried leaves and roasted leaves. L value, a value, and b value of Perilla leaf were the highest in the roasted leaves followed by the order of dried leaves and fresh leaves. L value and b value of Jasosuksu extracted from roasted leaves were higher than Jasosuksu extracted from dried leaves. The preference of color, flavor, sweetness of Jasosuksu extracted from dried leaves was the highest when extraction time was 10 min. at $70^{\circ}C$, but that of Jasosuksu extracted from roasted leaves was the highest when extraction time was 15 min. at $70^{\circ}C$. The preference of color, flavor, taste of Jasosuksu extracted from roasted leaves was higher than that of Jasosuksu extracted from dried leaves.

• Food Science and Preservation
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• v.17 no.5
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• pp.733-740
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• 2010

Brown rice vinegars were prepared by agitated or static acetic acid fermentation using different yeast strains (Saccharomyces kluyveri DJ97, Saccharomyces cerevisiae JK99, Saccharomyces cerevisiae GRJ, or Saccharomyces cerevisiae H9). Organic acid contents and levels of volatile compounds were compared in vinegars prepared by different methods. The chosen yeast strain did not significantly affect the organic acid content of vinegar. In vinegars prepared by agitated acetic acid fermentation, organic acid contents were, in the order of descending abundance, acetic acid, citric acid, lactic acid, oxalic acid, and tartaric acid. In vinegars prepared by static acetic acid fermentation, no citric acid was detected, and lactic acid content was higher than that in agitated acetic acid fermented vinegar. The volatile compounds of both vinegars, analyzed by GC-MS, did not significantly differ when various yeast strains were used. Eighteen volatile compounds were detected in vinegar prepared by agitated acetic acid fermentation and 11 in vinegar prepared by static fermentation. Volatile compounds that can affect vinegar quality, including ethyl acetate and phenethyl acetate, were present at high concentrations in static acetic acid fermented vinegar. Electronic nose analysis showed that volatile chemical patterns differed between the two types of vinegar, but there were no significant differences in sensory scores between vinegars prepared using various yeast strains or by either of the two methods of fermentation.