• Asian Journal of Atmospheric Environment
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• v.12 no.2
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• pp.178-191
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• 2018

The concentrations and chemical compositions of volatile organic compounds (VOCs), including volatile fatty acids, phenols, indoles, aldehydes, and ketones, which are the main organic compounds generated by swine, were investigated in July and October 2016 and January 2017. In addition, the emission rates and annual emissions of these components from the swine shed were estimated. The concentrations of VOCs in the swine shed averaged $511.3{\mu}g\;m^{-3}$ in summer, $315.5{\mu}g\;m^{-3}$ in fall and $218.6{\mu}g\;m^{-3}$ in winter. Acetone, acetic acid, propionic acid, and butyric acid were the predominant components of the VOCs, accounting for 80-88% of the total VOCs. The hourly variations of VOC concentrations in the swine shed in fall and winter suggest that the VOC concentrations were related to the ventilation rate of the swine shed, the activity of the swine, and the temperature in the swine shed. Accordingly, the emission rates of VOCs from the swine shed were $1-2{\times}10^3{\mu}g(h\;kg-swine)^{-1}$.

• Korean Journal of Food Science and Technology
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• v.41 no.3
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• pp.296-301
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• 2009

In order to investigate the effect of different yeasts (La Parisienne (LP), Y18-2, Y54-3, Y90-2, Y90-9 and Y272-7) from nuruks on the quality of Glutinous rice wines, physicochemical properties and volatile flavor components were evaluated. Glutinous rice wines prepared with different yeasts were analyzed for ethanol, pH, total acid, amino acid, soluble solid, coloring degree, UV absorbance, reducing sugar, organic acid, free sugar and volatile compounds. After fermentation for 17 days, the ethanol contents ranged from 13.40 to 14.50%, while the total acid levels were from 0.33 to 0.44%. The amino acid contents in six samples ranged from 0.13 to 0.18%, while soluble solid contents ranged from 12.1 to $14.7^{\circ}Bx$. The glutinous rice wine prepared with LP showed the highest level of coloring degree, soluble solid and reducing sugar among six samples. Organic acid contents of the glutinous rice wine prepared with LP had the highest levels of lactic acid and acetic acid, while the glutinous rice wine prepared with Y90-9 had the highest level of succinic acid. In all glutinous rice wines tested, the most abundant free sugars were glucose followed by maltose. Volatile flavor components in the glutinous rice wines were identified by using GC-MSD. Nineteen esters, ten alcohols, eight acids, one aldehyde and one miscellaneous compound were identified in the glutinous rice wines. Using relative peak area, it was found that other than ethyl alcohol, hexadecanoic acid ethyl ester was the major component, predominantly found in the range of 2.73-10.41%. Phenylethyl alcohol, isoamyl alcohol, ethyl oleate, ethyl linoleate and tetradecanoic acid ethyl ester were some of the major volatile components present through the fermentation, respectively. Overall, it was shown that different yeast strains from nuruks greatly affected chemical and volatile characteristics of the glutinous rice wines.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.8
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• pp.1168-1174
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• 2017

Objective: The aim of the study was to evaluate the effects of different nitrate levels (150, 300, 450, and 600 ppm $KNO_3$) on the volatile compounds and some other properties of pastırma. Methods: Pastırma samples were produced under the controlled condition and analyses of volatile compounds, and thiobarbituric acid reactive substances (TBARS) as an indicator of lipid oxidation, non-protein nitrogenous matter content as an indicator of proteolysis, color and residual nitrite were carried out on the final product. The profile of volatile compounds of pastırma samples was analyzed by gas chromatography/mass spectrometry using a solid phase microextraction. Results: Nitrate level had a significant effect on pH value (p<0.05) and a very significant effect on TBARS value (p<0.01). No significant differences were determined in terms of $a_w$ value, non-protein nitrogenous substance content, color and residual nitrite between pastırma groups produced by using different nitrate levels. Nitrate level had a significant (p<0.05) or a very significant (p<0.01) effect on some volatile compounds. It was determined that the amounts and counts of volatile compounds were lower in the 450 and especially 600 ppm nitrate levels than 150 and 300 ppm nitrate levels (p<0.05). While the use of 600 ppm nitrate did not cause an increase in residual nitrite levels, the use of 150 ppm nitrate did not negatively affect the color of pastırma. However, the levels of volatile compounds decreased with an increasing level of nitrate. Conclusion: The use of 600 ppm nitrate is not a risk in terms of residual nitrite in pastırma produced under controlled condition, however, this level is not suitable due to decrease in the amount of volatile compounds.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.2
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• pp.298-305
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• 2016

Prior research has attempted to develop a method for fermentation of onion vinegar to satisfy customer quality standard. Onion wine (OW) and onion vinegar (OV) were produced by alcoholic and acetic fermentation of onion extracts (OE) using Saccharomyces cerevisiae and Acetobacter pasteurianus, and their taste compounds (non-volatile organic acids, non-protein N compounds, and free sugars) were determined. Main components of non-volatile organic acids were malic acid (50.1%) and citric acid (26.9%) in OE, whereas malic acid (28.1%), acetic acid (20.8%), lactic acid (20.1%), citric acid (13.3%), and succinic acid (12.0%) were detected in OW. Total concentrations of non-volatile organic acids in OV were 4,612.0 mg/100 g, which was 3.9 and 2.3 times higher than those of OE and OW, respectively. Non-volatile organic acids except malonic acid and acetic acid were reduced during acetic fermentation. Non-protein N compounds increased 4.23-fold ($41,526.8{\mu}g/100g$) during alcohol fermentation, and urea content was the highest of non-protein N compounds at $33,816{\mu}g/100g$. The reduced values in OV might be used as a nutritious element of Acetobacter pasteurianus. Free sugars (glucose, fructose, and sucrose) were detected in OE, whereas only fructose was absent in OW and OV.

• Korean Journal of Food Science and Technology
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• v.39 no.6
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• pp.593-599
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• 2007

In this study, we examined the volatile flavor components in the mashes of takju prepared using different yeasts such as Saccharomyces coreanus, S. ellipsoideus, S. carlsbergensis, S. cerevisiae (Baker's yeast), and S, rouxii by GC and GC-MS. Fourteen alcohols, 13 esters, 5 acids, 3 aldehydes, 7 amines, and 2 other compounds were identified in the mash after 6 days of fermentation. On day 6, the takju fermented by S. coreanus had the greatest variety of volatile flavor components. Fifteen flavor components, including ethanol, isobutyl alcohol, isoamyl alcohol, methyl pentanol, 1,3-butanediol, 3-methylthio-1-propanol, benzeneethanol, ethyl lactate, acetic acid, acetaldehyde, and 1,3-cyclohexane diamine, were typically detected in all the treatments. The relative peak areas of the volatile components were as follows: alcohols (96.758-99.387%), esters (0.081-0.968%), acids (0.040-0.640%), aldehydes (0.266-0.959%), and amines (0.011-0.047%). In particular, 1-propanol, isobutyl alcohol, 3-methyl-1-butanol, 2,3-butanediol, trimethyl benzylalcohol, heptene-2,4-diol, ethyl lactate, diethyl succinate, ethyl nonanoate, methyl hexadecanoate, linoleic acid, hexadecanoic acid, and acetaldehyde were hish in the takju made by S. coreanus. Also, ethyl stearate was high in the takju made by S. carlsbergensis, and hexanoic acid was high in the takju made by S. cerevisiae. Finally, methyl pentanol, 1,3-butanediol, 3-methylthio-1-propanol, benzene ethanol, ethyl octadecanoate, acetic acid, pentanal, and 1,3-cyclohexane diamine were high in the takju made by S. rouxii.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.7
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• pp.822-832
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• 2017

This study analyzed contents of organic acids, free sugars, and volatile flavor compounds by type of Jerusalem artichoke (Helianthus tuberosus L.). Organic acids in dried Jerusalem artichoke were mainly composed of malic acid, citric acid, and succinic acid. Sucrose, fructose, and glucose were the major sugar components of dried Jerusalem artichoke. Free sugars were more abundant in the white colored sample than in the purple colored sample. In contrast, purple colored sample contained more organic acids than the white colored one. Volatile compounds in Jerusalem artichoke were investigated using the solid-phase micro-extraction method of gas chromatography/mass spectrometry. A total of 117 volatile compounds were identified in Jerusalem artichoke, and chemical classification was as follows: 5 acids, 13 alcohols, 19 aldehydes, 12 hydrocarbons, 15 ketones, 8 miscellaneous, 27 pyrazines, and 18 terpenes in all samples. Terpene was the most abundant in Jerusalem artichoke, and ${\beta}$-bisabolene was the main component in terpenes. The second most common compound was aldehyde, and hexanal was the highest. Pyrazines were the most abundant in the roasted samples, and 2,5-dimethyl-3-ethylpyrazine was present at the highest level, followed by 2,5-dimethylpyrazine. Compared with purple samples, main compounds contained in white samples were aldehydes and hydrocarbons, whereas the major compounds in purple samples were terpenes and alcohols.

• Korean Journal of Food Science and Technology
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• v.42 no.1
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• pp.75-81
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• 2010

In order to investigate the effects of different milling degrees on the quality of glutinous rice wines, the physicochemical properties and volatile compounds of various wines were evaluated. Sample wines prepared from glutinous rice with 90, 80, and 70% milling yields were analyzed for ethanol, pH, total acids, amino acids, soluble solids, coloring degree, UV absorbance, reducing sugars, organic acids, free sugars and volatile compounds. After fermentation for 17 days, ethanol contents in the wines ranged from 15.2 to 15.85%, while total acid levels ranged from 0.31 to 0.35%. The amino acid contents in four samples ranged from 0.63 to 0.73%, while soluble solid contents ranged from 11.4 to $13.1^{\circ}Bx$. The wine prepared from glutinous rice with a 30% degree of milling showed the highest coloring degree, UV absorbance and reducing sugar content among four samples. Furthermore, this wine had the highest levels of malic acid and acetic acid, while the glutinous rice wine prepared from rice with a 0% degree of milling had the highest levels of succinic acid and lactic acid. In all the glutinous rice wines tested, the most abundant free sugar was glucose followed by maltose. With increasing degree of milling, the alcohol, amino acid and organic acid contents of the glutinous rice wines decreased, whereas soluble solids, coloring degree, UV absorbance, reducing sugar and free sugar contents increased. Volatile compounds were identified using GC-MSD, and thirty-nine esters, seven alcohols, six acids, one aldehyde, four alkanes, one alkene and two miscellaneous compounds were identified in the glutinous rice wines. Using relative peak area, it was determined that other than ethyl alcohol, hexadecanoic acid ethyl ester was the major component and was primarily found in the range of 11.566-18.437%. Succinic acid diethyl ester and isoamyl laurate decreased with an increasing degree of milling, whereas hexanoic acid ethyl ester and 2-octenoic acid ethyl ester increased. Overall, it was shown that different milling degrees greatly affected the physicochemical and volatile characteristics of the glutinous rice wines.

• Korean Journal of Food Science and Technology
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• v.39 no.2
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• pp.109-113
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• 2007

Adenophora remotiflora (Mosidae) is a perennial plant in the Campanulaceae family and a wild plant that only inhabits in Korea. This research analyzed the volatile compounds in Mosidae and their antioxidant activities. The volatile compounds in fresh, shady air-dried, and freeze-dried Mosidae were isolated by steam-distillation extraction (SDE) method using diethylether as a solvent. Volatile compounds were analyzed by gas chromatography-mass spectrometry (GC/MS). Antioxidant activities were determined using the linoleic acid system and 1,1-diphenyl-2-picrylhydrazyl (DPPH) method. Sixty and seventy-two volatile compounds were identified from fresh and shady air-dried Mosidae, respectively. In fresh Mosidae, the most abundant compounds were ethyl acetate and heptyl acetate, while ethyl acetate and limonene were the most abundant in the shady air-dried sample. Inhibition of peroxide formation by fresh Mosidae was higher than that of ${\alpha}-tocopherol$, and inhibition by shady air-dried Mosidae was same as that of ${\alpha}-tocopherol$. Furthermore, volatile compounds from shady air-dried Mosidae had higher free radical scavenging activity than ${\alpha}-tocopherol$. The freeze-dried sample showed lower antioxidant activity in both the linoleic acid system and DPPH method.

• Food Science of Animal Resources
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• v.41 no.6
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• pp.936-949
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• 2021

This study discriminated fatty acid profile and flavor characteristics of Beijing You Chicken (BYC) as a precious local breed and Dwarf Beijing You Chicken (DBYC) eggs. Fatty acid profile and flavor characteristics were analyzed to identify differences between BYC and DBYC eggs. Four classification algorithms were used to build classification models. Arachidic acid, oleic acid (OA), eicosatrienoic acid, docosapentaenoic acid (DPA), hexadecenoic acid, monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA), unsaturated fatty acids (UFA) and 35 volatile compounds had significant differences in fatty acids and volatile compounds by gas chromatography-mass spectrometry (GC-MS) (p<0.05). For fatty acid data, k-nearest neighbor (KNN) and support vector machine (SVM) got 91.7% classification accuracy. SPME-GC-MS data failed in classification models. For electronic nose data, classification accuracy of KNN, linear discriminant analysis (LDA), SVM and decision tree was all 100%. The overall results indicated that BYC and DBYC eggs could be discriminated based on electronic nose with suitable classification algorithms. This research compared the differentiation of the fatty acid profile and volatile compounds of various egg yolks. The results could be applied to evaluate egg nutrition and distinguish avian eggs.

• Journal of the Korean Society of Food Culture
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• v.21 no.3
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• pp.319-324
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• 2006

Volatile compounds in low-temperature and long-term fermented Baechu kimchi were extracted by high vacuum sublimation(HVS), and then analyzed by gas chromatography/mass spectrometry(GC-MS). A total of 62 compounds, including 7 sulfur-containing compounds, 8 terpenes, 5 esters, 8 acids, 15 alcohols, 2 nitrites, 2 ketones, 11 aliphatic hydrocarbons and 4 miscellaneous compounds, were found in low-temperature and long-term fermented Baechu kimchi. Among them, acetic acid and butanoic acid were quantitatively dominant. Aroma-active compounds were also determined by gas chromatography/olfactometry(GC-O) using aroma extract dilution analysis(AEDA). A total of 16 aroma-active compounds were detected by GC-O. Butanoic acid was the most potent aroma-active compound with the highest FD factor($Log_3FD$) followed by linalool, acetic acid, 2-vinyl-4H-1,3-dithin and 3-methyl-1-butanol. The major aroma-active compounds, such as acetic acid and butanoic acid, were related to sour and rancid or notes.