• Food Science and Biotechnology
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• v.14 no.2
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• pp.249-254
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• 2005

The relationship between Sigumjang gas chromatographic patterns precisely analyzed with capillary column and ranked order in sensory analysis was investigated by stepwise multiple regression analysis. Highly predictable multiple regression models were obtained in the analysis. Ninety percent of the Sigumjang aroma was explained by the regression models at step 15 in four transformation except for absolute value transformed with root square and relative value transformed with logarithm. The aroma of Sigumjang was most affected by 2,3-dimethylpyrazine at absolute value and absolute value transformed with logarithm and by 2-furancarboxaldehyde in other transformation. The quality of sigumjang was highly affected by ${\beta}$-phallendrenal, methylpyrazine, tetramethylpyrazine, 5-methyl-2-furancarboxaldehyde, unknown 2, octanoic acid, 4-ethylphenol, methyl 10,13-octadecanoate and ethyl linoleate.

• Journal of Microbiology and Biotechnology
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• v.7 no.6
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• pp.391-396
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• 1997

Two series of carbon sources, linear primary $C_1$~$C_9$ alcohols and linear $C_2$~$C_{10}$ monocarboxylic acids were tested for PHA synthesis in Paracoccus denitrificans. The results showed that the growth-associated synthesis of PHA could be referred only to the carbon sources with odd number of carbon except methanol. For all carbon sources with even number of carbon, nitrogen limitation was required to induce PHA synthesis in P. denitrificans. Poly(3-hydroxyvalerate)[P(3HV)] homopolymer was synthesized from $C_5$, $C_7$, and $C_9$ while growing in the presence of nitrogen, but the nitrogen depletion in the later growth period incorporated 3-hydroxybutyrate(3HB) unit into the polymer chain. The optimum C/N ratio for P(3HV) homopolymer production was found to be 10 when the strain was grown on 10 ml/l of valeric acid for 96 h. P. denitrificans synthesized P(3HB-co-3HV) copolymers from n-hexanoic and n-octanoic acid. The microstructural characterics of the P(3HB-co-3HV) copolymer from n-propanol was investigated using $^13C$-nuclear magnetic resonance spectroscopy, showing a structural heterogeneity.

• Korean Journal of Medicinal Crop Science
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• v.17 no.3
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• pp.179-186
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• 2009

The chemical composition of essential oil from the perennial herbaceous plants (Houttuynia cordata, Filipendula glaberrima, Peucedanum japonicum, and Ainsliaea acerifolia) was determined by GC/MS spectrometric analysis with the aid of NBS, Wiley Library and RI indice searches. The major constituents identified were $\alpha$-phellandrene (18.97%), $\gamma$-terpinene (12.32%), decanal (8.72%), 1-decanol (10.92%), decanoic acid (12.12%), and 2-undecanone (12.32%) from H. cordata, farnesol (2.83%), l-$\alpha$-terpineol (2.72%), benzenmethanol (2.03%), (Z)-3-hexen-1-ol (4.32%), and T-muurolol (2.07%) from F. glaberrima, $\alpha$-phellandrene (14.25%), endobornyl acetate (3.84%), heptanal (47.52%), octanal (2.65%), (E,E)-2,4-decadienal (2.75%), and octanoic acid (4.52%) from P. japonicum, and geyrene (9.74%), $\beta$-cubebene (11.15%), berkheyaradulen (22.32%), $\beta$-elemene (6.21%), (-)-A-selinene (4.85%), benzaldehyde (4.52%), and benzenacetaldehyde (3.40%) from A. acerifolia.

• Journal of the Korean Applied Science and Technology
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• v.20 no.1
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• pp.20-26
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• 2003

Acidic degreasing agent(AADA) was prepared by blending sorbitol, Newpol PE-68, Na-dioctyl sulfosuccinate, Tetronix T-70l, MJU-100A, n-octanoic acid, and phosphoric acid, The physical properties of AADA tested with aluminum specimen showed the following results ; when 3wt% AADA-5 was performed at 70$^{\circ}C$, the degreasing rate was 95% which is comparitively good, and the percentage of etching was 0.277% which was found to be less than that of commercialized product. when 20wt% of AADA-5 was added at 65$^{\circ}C$, the percentage of derusting was 91% and the good defoaming effect proved by following low foaming power tests respectively : Ross and Miles, and Ross and Clark methods.

• Journal of the Korean Applied Science and Technology
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• v.14 no.3
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• pp.71-77
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• 1997

Low foaming acidic degreasing agent(LFADAs) were prepared by blending sorbitol, n-octanoic acid, MJU-100A, Tetronix T-701, Na-dioctyl sulfosuccinate, Demol C, and phosphoric acid. The physical properties of LFADAs tested with aluminum specimen showed the following results ; when 3wt% LFADA-6 was performed at $70^{\circ}C$, the degreasing rate was 95% which is comparitively good, and the percentage of etching was 0.275% which was found to be less than that of commercialized product. When 20wt% of LFADA-6 was added at $65^{\circ}C$, the percentage of derusting was 92% and the good defoaming effect proved by following low foaming power tests respectively : Ross and Miles, and Ross and Clark methods.

• Journal of Microbiology and Biotechnology
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• v.15 no.6
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• pp.1330-1336
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• 2005

Polyhydroxyalkanoic acid (PHA) inclusion bodies were analyzed in situ by $^{13}C$-nuclear magnetic resonance ($^{13}C$-NMR) spectroscopy. The PHA inclusion bodies studied were composed of poly(3-hydroxybutyrate) or poly(3hydroxybutyrate-co-4-hydroxybutyrate), which was accumulated in Hydrogenophaga pseudoflava, and medium-chain-length PHA (MCL-PHA), which was accumulated in Pseudomonas fluorescens BM07 from octanoic acid or 11-phenoxyundecanoic acid (11-POU). The quantification of the $^{13}C$-NMR signals was conducted against a standard compound, sodium 2,2-dimethyl-2-silapentane-5-sulfonate (DSS). The chemical shift values for the in vivo NMR spectral peaks agreed well with those for the corresponding purified PHA polymers. The intracellular degradation of the PHA inclusions by intracellular PHA depolymerase(s) was monitored by in vivo NMR spectroscopy and analyzed in terms of first-order reaction kinetics. The H. pseudoflava cells were washed for the degradation experiment, transferred to a degradation medium without a carbon source, but containing 1.0 g/l ammonium sulfate, and cultivated at $35^{\circ}C$ for 72 h. The in vivo NMR spectra were obtained at $70^{\circ}C$ for the short-chain-length PHA cells whereas the spectra for the aliphatic and aromatic MCL-PHA cells were obtained at $50^{\circ}C\;and\;80^{\circ}C$, respectively. For the H. pseudoflava cells, the in vivo NMR kinetics analysis of the PHA degradation resulted in a first-order degradation rate constant of 0.075/h ($r^{2}$=0.94) for the initial 24 h of degradation, which was close to the 0.050/h determined when using a gas chromatographic analysis of chloroform extracts of sulfuric acid/methanol reaction mixtures of dried whole cells. Accordingly, it is suggested that in vivo $^{13}C$-NMR spectroscopy is an important tool for studying intracellular PHA degradation in terms of kinetics.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.22 no.4
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• pp.169-176
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• 1989

Volatile flavor components in powdered Katsuobushi were simultaneous trapped by steam distillation-extraction method, and these were fractionated into the neutral, the phenolic, the acidic and the basic fraction. Volatile flavor components in these fraction were analyzed by the high-resolution GC and GC-MS equipped with a fused silica capillary column. The whole steam volatile concentrate consisted of $48\%$ neutral fraction(NF), $35\%$ phenolic fraction(PF), $12\%$ acidic fraction(AF) and $5\%$ basic fraction(BF). Thirty components such as 8 hydrocarbons, 8 aldehydes, 6 furans, 5 alcohols and 3 ketones were identified from NF. And sixteen components such as phenol, guaiacol, dimethoxy phenol, eugenol in PF, twelve components such as propionic, butanoic, isopentanoic, n-hexanoic, heptanoic, octanoic acid in AF, ten components such as 2,6-dimethylpyrazine, 2-nethylpyridine, 2,4-dimethylthiaBole in BF were identified. NF and PF gave a much higher yield than others and were assumed to be indispensable for the reproduction of aroma of powdered Katsuobushi. It was also identified eight components of volatile carbonyl compounds such as ethanal, propanal, butanal, pentanal by 2,4-DNPH method.

• The Korean Journal of Food And Nutrition
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• v.30 no.4
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• pp.813-822
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• 2017

To investigate the aroma and quality characteristics of wine bestowed by the degree of ripening of Cheongporang grapes, the general quality composition, color, organic acid, physiological activity, aroma component and sensory evaluation were analyzed. The general characteristics of the wine assessed were pH 3.34~3.50, total acidity 0.46~0.67%, color intensity 0.074~0.116, lightness 98.99~99.74, redness -0.39~0.01, and yellowness was 1.52~3.10. Malolactic fermentation was not relative to the contents of malic acid and lactic acid. The total polyphenol content and antioxidant activity were lowest in C3 wines made with ripe grapes and highest in C4 wines made with mixed grapes. Aroma analysis identified 6 alcohols, 15 esters and 5 miscellaneous compounds. Compounds with higher odor activity value (OAV) were 3-methyl-1-butanol, ethyl butanoate, isopentyl acetate, ethyl hexanoate, ethyl octanoate, ethyl decanoate and octanoic acid. The C4 wine, a mixture of grapes with different degrees of ripening, had the highest ester content and ratio. The lowest values were found in the C3 wine made with ripe grapes. Results of the sensory evaluation related the C4 wine, containing a large amount of ester compounds having high OAV values as the aroma component, as the best and most preferred wine.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.3
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• pp.300-306
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• 1993

Speries-related meat flavors were investigated for red meats (bovine, porcine, caprine, and ovine). Volatile branched-chain fatty acids (VBCFAs) including 2-methylbutanoic, 3-methylbutanoic, 4-methylpentanoic, 2-ethylhexanoic, 4-methylhexanoic, 4-methyloctanoic, 6-methyloctanoic, 4-ethyloctanoic, 4-methylnonanoic, and 2-ethyldecanoic acids were identified in the meats from cow (bovine), pig (porcine), goats (caprine ; American white goat and Korean black goat), and lamb (ovine). Beef flavor of bovine meat was characterized by the basic meaty flavor, lacking in goaty and muttony flavor impacts due to low or absent in 4-methyl.octanoic and 4-ethyloctanoic acids. Porcine meat contained the least number of VBCFAs among sample species tested, and 3-methylbutanoic acid contributed to the unclean sweaty odor of pork. Caprine meat from Korean black and American white goats lacked in short VBCFAs (C5, C6, and C7) and contained 4-methyloctanoic and 4-ethyloctanoic acids contributing to the characteristic goaty flavor of caprine meat. Caprine meat flavor was distinctively characterized by 4-ethyloctanoic acid, while 4-methyloctanoic acid provides sweaty-muttony flavor to ovine meat. Although kinds of VBCFAs are same in two different varieties of caprine meats, meat sample from Korean black goat had stronger goaty odor and contained higher concentration of 4-ethyloctanoic acid than the meat sample from American white goat did.

• Food Engineering Progress
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• v.13 no.4
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• pp.302-307
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• 2009

In this study, four Korean black raspberry wines were developed from different regions in Korea; Gochang (G), Heongsung (H), Jeongup (J), and Sungchang (S). Their flavor profiles were determined using a combination of volatile analysis and sensory evaluation. From the volatile analysis of the developed wines, 8 acids, 17 alcohols, 12 esters, 9 terpenes, 3 aldehydes and ketones, and 4 miscellaneous compounds were identified. Preferences of appearance, aroma, full-body, and overall acceptability in the developed wines were determined using 9-point hedonic scale by 43 panelists, compared with one commercial black raspberry wine (Sunw). The sweetness, sourness, astringency levels were also evaluated using 9-point just-about-right (JAR) scale. The mean overall acceptability score of Sunw (5.58) was the highest among the tested wines, followed by G (4.81), S (4.44), H (4.41), and J (4.13) (p<0.05). Sweetness levels in the developed wines were overall lower than JAR level, while sourness and astringency levels were overall higher than JAR level.