• Korean Journal of Food Science and Technology
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• v.20 no.4
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• pp.606-612
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• 1988

The volatile flavor compounds of fresh and dried shiitake mushrooms(Lentinus edodes) were extracted by simultaneous steam distillation-extraction apparatus, and analyzed by combined GC and GC-MS, and effects of pH on the formation of volatile compounds in fresh shiitake mushroom were investigated. Of the 29 compounds identified from fresh shiitake mushroom, the main volatile compound was 1-octen-3-ol comprising about 74.7% of the total volatiles and that in dried shiitake mushroom was 1, 2, 4-trithiolane comprising about 66.3%. With the exception of above two compounds, 3-octanone, 1-octen-3-one, 3-octanol, cis-2-octenal, n-octanol and cis-2-octenol as $C_8$ compounds were identified. Carbon disulfide, dimethyl disulfide, dimethyl trisulfide, 1-(methyl thio)-dimethyl disulfide, 1, 2, 4, 5-tetrathiane as sulfurous compounds were also identified. The formation of $C_8$ compounds in fresh shiitake mushroom during immersion was dominant in the range of pH 6.0 to 7.0, while the formation of sulfurous compounds in the range of pH 8.0 to 9.0.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.8
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• pp.1336-1344
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• 2018

Objective: This study aimed to observe whether high-pressure processing (HPP) affected aroma development and the degradation rate of umami taste-related ATP breakdown products, specifically inosinic acid in grass-fed beef during vacuum aging. Methods: Strip loin (longissimus lumborum) cuts obtained from six grass-fed Friesian Holstein steers (32 months old) on day 4 post slaughter were vacuum-packed and subjected to pressurization at 300 and 500 MPa for 180 s at $15^{\circ}C{\pm}2^{\circ}C$. The samples were then stored for 4 weeks at $5^{\circ}C{\pm}0.5^{\circ}C$ under vacuum and compared with the control (0.1 MPa). Results: HPP increased the shear force value, promoted moisture loss and lipid oxidation, induced surface paleness, stabilized pH during aging, and reduced bacterial load and growth. The shear force value of 500 MPa-treated samples remained higher than the control after aging, while no significant differences were found between the control and 300 MPa-treated samples. Degradation of inosinic acid and inosine occurred during pressurization, resulting in an increase in hypoxanthine content. However, the degradation rate in HPP-treated samples during aging was slower; therefore, inosinic acid and inosine content remained higher than in control samples. No significant differences were found in hypoxanthine content at the end of aging. HPP intensified the levels of hexanal, octanal, 2-methylbutanal, 3-methylbutanal, benzaldehyde, and 2,5-dimethylpyrazine in cooked-aged beef samples. Conclusion: HPP induced aroma development and delayed the degradation of inosinic acid. However, it also reduced the postmortem tenderization rate.

• Food Science and Preservation
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• v.18 no.5
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• pp.803-810
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• 2011

This study was performed to evaluate the quality of the commercial brown-rice vinegars of South Korean and Japanese origins, which were prepared via static acetic-acid fermentation. The major free amino acids of Korean brown-rice vinegars were proline, glutamic acid and phenylalanine, while those of the Japanese were proline, valine, phenylalanine, lysine, ${\gamma}$-aminobutyric acid, alanine and isoleucine. The ${\gamma}$-aminobutyric acid (GABA) and total amino acids (3686.37~4212.27 mg%) contents were found to be significantly higher in the Japanese than in the Korean brown-rice vinegars. The key volatile compounds of the Korean brown-rice vinegars, analyzed with GC-MS, were acetic acid, benzaldehyde, phenethyl alcohol and phenethyl acetate while those of the Japanese brown-rice vinegars were acetic acid, ethyl acetate, ethyl alcohol, isoamyl acetate, phenethyl acetate and benzaldehyde. The volatile patterns of the Korean and Japanese commercial brown-rice vinegars were effectively distinguished from each other using an electronic nose, through which it was also elucidated that the volatiles profiles were similar among the Japanese vinegars but were different among the Korean vinegars.

• Korean Journal of Food Science and Technology
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• v.28 no.6
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• pp.1171-1176
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• 1996

The changes in volatiles of the model system were analyzed by GC and GC-MS before and after retorting. The GC data were analyzed statistically by applying the analysis of variance, and 42 peaks were selected at 5% significance level. Multivariate statistical analysis was performed with these 42 peaks as independent variables. Through the stepwise discriminant analysis, 8 peaks, which corresponded to the compounds such as 2-heptanone, cis-3-hexenal, 2-pentyl-furan, 1-methyl-trans-1,2-cyclohexanediol, 2-hexanone, 3-octanone, trans, trans-nona-2,4-dienal and 1-octen-3-ol, were obtained in sequence to distinguish the samples with and without retorting. The principal component analysis of a set of 8 independent variables resulted in 3 principal components which accounted for 96.1% of the variance, while the first principal component (PC 1) explained 76.5% of the total variance. In addition, through the factor analysis of the principal components, the peaks 11, 20 and 21 could be grouped togather in accordance with the direction and the size while the peaks 9, 33 and 39 constituted the second group in the direction.

• Journal of the Korean Society of Food Science and Nutrition
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• v.16 no.3
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• pp.27-34
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• 1987

The present paper was attempted to obtain the basic date concerning a reasonable preparing method and optimum fermentation conditions of Kochujang (Red pepper paste). To establish the standard quality of Kochujang, the chemical compositions and the volatile components of Kochujang was discussed. The native Kochujang collected from 80 households contained 40.51% of moisture, 6.00% of salts, 3.25 % of crude fat, 10.30 % of crude ash, pH 4.79, 9.28ml of tillable acidity. 19.60% of reducing sugar, 179.51 mg/100g of amino nitrogen and 4.43% of total nitrogen. The volatiles of Kochujang were extracted by a steam-distillation under the reduced pressure and determined by gas chromatography-mass spectrometry (GC-MS). Total volatile components identified in the native Kochujang were 46 components, i. e., 30 components in neutral fraction, 8 components in phenolic fraction and 8 components in acidic fraction, respectively. But no components were detected basic fraction.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.34 no.3
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• pp.259-267
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• 2010

In this study, the effect of particle size on the combustion characteristics of pulverized sub-bituminous coal was experimentally investigated. A laminar-flow-entrained reactor was designed and implemented to realize the desired heating ratio and temperature corresponding to the combustion atmosphere of a pulverized-coal-fueled furnace. The flame length and structure of burning particles according to different sizes were investigated. Coal combustion processes were clearly distinguished by direct visual observation of the flame structure. The onset point of volatile ignition is greatly affected by changes in the particle size, and the burning time of the volatiles is least affected by changes in the particle size. The length and instability of char flame also increase with the increase of the particle size. However, the char consumption rate within the residential time remains nearly constant.

• Food Science and Preservation
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• v.18 no.4
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• pp.552-558
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• 2011

Hypsizigus marmoreus is a wild mushroom commonly consumed in South Korea due to its beneficial effects on health. In the present study, the general chemical and inorganic-element composition, the total amino acid contents, and the volatile-flavor compounds of H. marmoreus were investigated for food uses. The proximate compositions consisted of 60.1% carbohydrate, 32.0% crude protein, 8.98% moisture, 5.0% ash, and 2.0% crude lipid. The minerals in H. marmoreus were found to be as follows; potassium (429.5 mg), phosphorus (101.9 mg), sodium (20.3 mg), magnesium (54.86 mg), calcium (2.7 mg), zinc (0.8 mg), iron (0.7 mg), manganese (0.2 mg), and copper (0.1 mg), based on 100 g of mushroom dry weight. Seventeen kinds of total amino acids were found in H. marmoreus, with the glutamine acid content being the highest (2,340 mg/100 g), followed by the asparagine, serine, arginine, and leucine contents. The volatile-flavor components of H. marmoreus were collected via simultaneous steam distillation extraction (SDE), and were analyzed via gas chromatography-massspectrophotometry (GC-MS). A total of 17 volatile-flavor compounds were identified, including eight aldehydes, seven alcohols, one acids, and one other compounds. The most abundant compound was 2,3,6-trimethy1 pyridine, which accounted for more than 40% of the total volatiles; other important compounds were 1-octen-3-o1, buty1hydroxytoluene (BHT), isoocty1 phthalate, 3-octanal, 1-undecanol, and 2-amylfuran. These results provide preliminary data for the development of H. marmoreus as an edible food material.

• Food Science and Preservation
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• v.17 no.6
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• pp.770-776
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• 2010

Sarcodon aspratus (Berk.) S. Ito is a wild mushroom commonly consumed in Korea due to its beneficial effects on health. However, only limited information on the volatile and nonvolatile constituents of S. aspratus is available. In the present study, the total concentration of mushroom soluble sugars, including glucose, trehalose, sucrose, and xylose, was found to be 202.5 mg/kg. The total contents of free and essential amino acids were 2,592.1 mg/kg and 1,249.5 mg/kg, respectively; arginine, lysine, methionine, and valine were the major amino acids present. The contents of total 5'-nucleotides and flavor 5'-nucleotides in S. aspratus were 2,510.7 mg/kg and 773.4 mg/kg, respectively. The volatile components of S. aspratus were collected by simultaneous distillation-extraction (SDE) and analyzed by gas chromatography-massspectrometry (GC-MS). A total of 27 volatile compounds were isolated and identified. The most abundant was l-octen-3-ol, which accounted for more than 68% of total volatiles; other important compounds were 2-octen-1-ol, 1-octen-3-one, and 2-octenol. Our results provide preliminary data for the development of S. aspratus as a food material.

• Food Science and Preservation
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• v.23 no.7
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• pp.977-988
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• 2016

The volatile flavor compounds in five Jeju citrus fruit varieties (Cheonhyehyang, Hallabong, Jinjihyang, Hwanggeum hyang and Redhyang) were extracted by simultaneous distillation-extraction (SDE) using solvent mixture of n-pentane and diethyl ether (1:1, v/v) and analyzed by using gas chromatography-mass spectrometry (GC-MS). The number of aroma compounds were identified with : 104 (4,939.77 mg/kg) in Cheonhyehyang, 98 (3,286.38 mg/kg) in Hallabong, 105 (3,317.56 mg/kg) in Jinjihyang, 102 (4,293.39 mg/kg) in Hwanggeumhyang, and 108 (4,049.94 mg/kg) in Redhyang. The detected main volatile compounds were; limonene, sabinene, ${\beta}$-myrcene, ${\alpha}$-pinene, ${\beta}$-pinene, linalool, 4-terpineol, ${\alpha}$-terpineol, (E)-${\beta}$-ocimene and ${\gamma}$-terpinene. Among the identified volatiles compounds, ethyl-benzene, nonanol, 1-p-menthen-9-al, (E)-isocarveol, methyl salicylate, ${\alpha}$-terpinen-7-al, perilla alcohol, and ethyl-dodecanoate were detected in Cheonhyehyang. only Furthermore, ${\beta}$-chamigrene and ${\alpha}$-selinene were in Hallabong only; 3-hydroxybutanal, (E)-2-nonenal, isoborneol, octyl acetate, (E)-2-undecenal, ${\beta}$-ylangene and guaia-6,9-diene in Jinjihyang. ${\rho}$-Cymenene, ${\beta}$-thujone, selina-4,11-diene and (E,E)-2,6-farnesol in Hwanggeumhyang only; and ${\rho}$-cymen-8-ol, bornyl acetate, carvacrol, bicycloelemene, ${\alpha}$-cubebene and 7-epi-${\alpha}$-selinene in Redhyang only. This study confirmed the differences in composition and content of volatile aroma components in five varieties of Jeju citrus fruits.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.6
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• pp.892-898
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• 2005

The effect of gamma irradiation on volatile components of Korean dried ginger (Zingiber officinale Roscoe) was studied and compared with non-irradiated sample. Volatile compounds from non- and irradiated samples were extracted using simultaneous distillation-extraction (SDE) apparatus and analyzed by gas chromatography-mass spectrometer (GC/MS). A total of 83 and 71 compounds were identified and quantified from non-and irradiated dried ginger at dose of 10 kGy. Identified components were hydrocarbons, alcohols, aldehydes, esters, ketones and miscellaneous compounds. The terpenoid compounds in volatile flavor compounds identified from non and irradiatied dried ginger were $98.27\%\;and\;98.12\%$, respectively. $\alpha$ -zingiberene,$\beta$-sesquiphelland reno, geranial, (Z,E) $\alpha$ -farnesene, $\beta$ -phellandene were detected as major volatile compounds of two experimental sample. The amount of volatile components in the samples was changed by irradiation but the profile of volatiles in non- and irradiated dried ginger were the same.