• Food Science of Animal Resources
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• v.44 no.1
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• pp.165-177
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• 2024

Volatile compounds (VOCs) are an important factor affecting meat quality. However, the characteristic VOCs in different parts of donkey meat remain unknown. Accordingly, this study represents a preliminary investigation of VOCs to differentiate between different cuts of donkey meat by using headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) combined with chemometrics analysis. The results showed that the 31 VOCs identified in donkey meat, ketones, alcohols, aldehydes, and esters were the predominant categories. A total of 10 VOCs with relative odor activity values ≥1 were found to be characteristic of donkey meat, including pentanone, hexanal, nonanal, octanal, and 3-methylbutanal. The VOC profiles in different parts of donkey meat were well differentiated using three- and two-dimensional fingerprint maps. Nine differential VOCs that represent potential markers to discriminate different parts of donkey meat were identified by chemometrics analysis. These include 2-butanone, 2-pentanone, and 2-heptanone. Thus, the VOC profiles in donkey meat and specific VOCs in different parts of donkey meat were revealed by HS-GC-IMS combined with chemometrics, whcih provided a basis and method of investigating the characteristic VOCs and quality control of donkey meat.

• Korean Chemical Engineering Research
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• v.50 no.4
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• pp.672-677
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• 2012

Lipids in microalgal biomass were recovered by using pyrolysis method. The pyrolysis experiments of two Chlorella sp. KR-1 samples, which have triglyceride contents of 10.8% and 36.5%, respectively were carried out at $600^{\circ}C$ to investigate the effects of lipid contents in the cells on the reaction characteristics. The conversion and liquid yield of the lipid-rich sample were higher than those of the lipid-lean sample since its carbon to hydrogen ratio was low. There were low molecular weight organic acids, ketones, aldehydes and alcohols in the liquid products from both KR-1 samples, but the pyrolysis oil of the lipid-rich sample was abundant in free fatty acids, particularly palmitic acid, oleic acid and stearic acid while the content of nitrogen containing organic compounds was low. The microalgal pyrolysis oil had two layers composed of the light hydrophobic fraction and the heavy hydrophilic fraction. The light fraction might be originated from triglycerides and the heavy fraction might be from carbohydrates and proteins. In the light fraction of the liquid products, there were considerable linear alkanes such as pentadecane and heptadecane as well as free fatty acids, implying that deoxygenation reaction including decarboxylation was occurred during the pyrolysis. The yield of the liquid products from the pyrolysis of the KR-1 sample having triglyceride content of 36.5% was 56.9% and the light fraction in the liquid products was 68.2%. Also more than 80% of the light fraction was free fatty acids and pure hydrocarbons, thus showing that most triglycerides could be extracted in the form of suitable raw materials for biofuels.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.16 no.4
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• pp.314-323
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• 2006

This study was conducted to identify ingredients of thinners and to confirm reliability of material safety data sheets (MSDS) of thinners for public and workers' health. The 41 thinner products were collected from paint shops located in Busan and Gyeongnam province. The 12 thinner products among them were identified using product MSDS. GC-MSD was used to analyze 41 kinds of thinners qualitatively and quantitatively. The 12 products MSDS were compared with thinner's component through qualitative analysis to confirm MSDS. Chemical ingredients, such as Benzene, Toluene, and Xylene etc., of thinners were analysed in quantity. The 41 thinner products contained 17 disclosed specific, trade name, or generically described chemical solvent ingredients. These 17 ingredients came under 6 classes: alcohols, aromatic hydrocarbons, esters, glycol ethers, ketones, and mixtures. These 17 ingredients were important in the view of industrial hygiene and had occupational exposure limit in the ambient, such as toluene, xylene, acetone, nonane, EGEE, heptane, cumene, MIBK, indene, tri-methyl benzene, etc, were found in 41 kinds of thinners. Aromatic hydrocarbons were the most identified ingredient in thinners. Especially, the benzene, which induces leukemia, was found in 4 kinds of thinners. The content rates of benzene in thinners were 0.25~1.18%. The benzene in enamel thinner, which were 0.39~0.72%, was highest from chemical classification. The contents of toluene, which was found from 27 kinds of thinners, were 5.35~64.16%, which were highest in sobu thinner as 58.80%. Xylene was found from 22 kinds of thinners and contents of xylene were 4.61~72.42%. Acrylic thinner's contents of xylene were 12.06~51.05%, which was most high. It was found that contents of benzene were increased and frequency of detection was decreased through comparison with other study. The MSDS possession rate of paint shops was low as 29.27%. So it did not provide information with public or workers. Mean of agreement rate between MSDS and components of thinners through qualitative analysis was 42.01% and it has wide range from 8.3% to 75%. There are many deficiencies in MSDS about component of thinners. In some case of sample, expecially, despite containing benzene, information was not written it on MSDS.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.8
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• pp.378-384
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• 2018

$C_9H_7NHCrO_3Cl$ was synthesized by reacting $C_9H_7NH$ with chromium (VI) trioxide. The structure of the product was characterized by FT-IR (Fourier transform infrared) spectroscopy and elemental analysis. The oxidation of benzyl alcohol by $C_9H_7NHCrO_3Cl$ in various solvents showed that the reactivity increased with increasing dielectric constant(${\varepsilon}$) in the following order: DMF (N,N'-dimethylformamide) > acetone > chloroform > cyclohexane. The oxidation of alcohols was examined by $C_9H_7NHCrO_3Cl$ in DMF. As a result, $C_9H_7NHCrO_3Cl$ was found to be an efficient oxidizing agent that converts benzyl alcohol, allyl alcohol, primary alcohols, and secondary alcohols to the corresponding aldehydes or ketones (75%-95%). The selective oxidation of alcohols was also examined by $C_9H_7NHCrO_3Cl$ in DMF. $C_9H_7NHCrO_3Cl$ was the selective oxidizing agent of benzyl, allyl and primary alcohol in the presence of secondary ones. In the presence of DMF with an acidic catalyst, such as $H_2SO_4$, $C_9H_7NHCrO_3Cl$ oxidized benzyl alcohol (H) and its derivatives ($p-OCH_3$, $m-CH_3$, $m-OCH_3$, m-Cl, and $m-NO_2$). Electron donating substituents accelerated the reaction rate, whereas electron acceptor groups retarded the reaction rate. The Hammett reaction constant (${\rho}$) was -0.69 (308K). The observed experimental data were used to rationalize hydride ion transfer in the rate-determining step.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.10
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• pp.1555-1564
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• 2014

This study investigated the effects of combined treatment of immersion liquids (adjusted pH 4.5 with Citrus junos concentrate (CL), pH 5.5 with Prunus mume concentrate (PL), or no pH adjustment, pH 6.5, control) and high hydrostatic pressure (HHP, 450 MPa) on shelf-life and quality of mackerel. In this study, we measured changes in viable cell counts, pH level, volatile basic nitrogen, thiobarbituric acid reactive substances, color analysis, volatile organic compounds, and sensory evaluation of mackerel at $4^{\circ}C$ for 20 days. CL/HHP and PL/HHP treatments reduced viable cell counts by 3 log cycles during storage compared to the control. Mackerel treated with CL/HHP and PL/HHP showed significantly lower TBARS and VBN levels as compared to the control. After combined treatment, lightness and whiteness increased but redness decreased. VOCs tests showed that contents of alcohol, acid, and ketones in mackerel fillet treated with CL/HHP and PL/HHP were relatively reduced. Especially, CL/HHP and PL/HHP suppressed production of sulfur. In the sensory evaluation, aroma, taste, salinity, hardness, and springiness of mackerel treated with combined HHP showed higher scores than the control. These results suggest that immersion liquids and HHP treatments may increase shelf-life of mackerel and maintain quality during storage at $4^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.50 no.2
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• pp.152-164
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• 2018

Fermented seasoning pastes were prepared by Aspergillus oryzae and Bacillus subtilis using three edible insects, Tenebrio molitor larvae (TMP), Gryllus bimaculatus (GBP), and Bombyx mori pupa (SPP), with soybean (SBP) as a negative control. Volatile compounds were extracted by the headspace solid-phase microextraction (HS-SPME) method and confirmed by gas chromatograph-mass spectrometry (GC-MS). In total, 121 volatiles from four samples were identified and sub-grouped as 11 esters, 18 alcohols, 23 aldehydes, 5 acids, 10 pyrazines, 2 pyridines, 7 aromatic hydrocarbons, 10 ketones, 19 alkanes, 9 amides, 4 furans and 3 miscellaneous. TMP, GBP, SPP and SBP had 48, 54, 36, and 55 volatile compounds, respectively. Overall, 2,6-dimethylpyrazine and trimethylpyrazine were found by a high proportion in all samples. Tetramethylpyrazine, a main flavor of doenjang, a Korean fermented seasoning soybean paste, was identified as one of the major compounds in TMP, SPP, and SBP. SBP had benzaldehyde, hexanal, n-pentanal, and aldehydes and SPP with pyrazines.

• Journal of Applied Biological Chemistry
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• v.60 no.3
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• pp.283-291
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• 2017

Rice that the half of population in the world eats as a staple food is mostly produced and consumed in Asia. However, its consumption is nowadays decreasing mainly due to diet diversity. Accordingly, some attempts are in demand to enhance the utilization of rice. In this study, profiling of volatile and non-volatile flavor components in rice pastes obtained by ${\alpha}$-amylase was performed and compared according to nine different rice cultivars domestically cultivated in Korea using gas chromatography-mass spectrometry combined by solid phase microextraction and gas chromatography-time of flight-mass spectrometry after a derivatization, respectively. In total, 46 volatile compounds identified included 6 alcohols, 6 aldehydes, 4 esters, 4 furan derivatives, 4 ketones, 1 acid, 1 sulfur-containing compound, 7 hydrocarbons, 5 aromatics and 8 terpenes. The non-volatile flavor components found were composed of 12 amino acids, 6 sugars and 4 sugar alcohols. In principal component analysis, rice paste samples could be discriminated according to cultivars on the score plots of volatile and non-volatile flavor compounds. In particular, some volatile compounds such as pentanal and 4,7-dimethylundecane could contribute to distinguish Senong 17 white and Senong 17 brown, whereas ethanol, 6-methylhep-5-en-2-one, and tridecane could be highly related to the discrimination of Iipum from other cultivars. Among non-volatile compounds, some amino acids such as glycine, serine and ${\gamma}$-aminobutyric acid and some sugars such as sucrose and fructose were mainly responsible for the discrimination of Danmi from the other cultivars. On the other hand, galactose, arabitol and mannose were more closely related to Senong 17 white than Senong 17 brown.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.1
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• pp.88-103
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• 2009

The volatile and semi-volatile compounds of 5 accessions of domestic scented and 25 accessions of introduced scented were extracted by solid phase microextraction (SPME) and analyzed by gas chromatographymass spectrum (GC-MS). A total of 156 volatile and semivolatile compounds were identified from 30 accessions of aromatic rice, including 32 alcohols, 25 acids, 25 ketones, 21 hydrocarbon, 18 esters, 16 aldehydes, 4 ethers, 5 amines, 2 phenols, 2 bases, and 8 miscellaneous compounds. By UPGMA/Neighbor-join tree analysis, the thirty accessions of aromatic rice could be classified into seven groups according to the major odor or aroma compounds. Group I included indica type of Basmati varieties. Group II and Group IV included japonica type introduced scented. Group III consisted only Hyangmibyeo1ho in domestic scented. Group V and Group VII included indica type of Basmati and non-Basmati varities. Group VI included four of domestic scented of seven accessions excepted Basmati6129, Basmati 6311, and Seratus Malam.

• Food Science and Preservation
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• v.24 no.2
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• pp.187-195
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• 2017

This study evaluated quality characteristics of soybean fermented by selected lactic acid bacteria, which were the enzyme strains with high antimicrobial activities isolated from traditionally prepared soybean paste. We determined total aerobic and lactic acid bacteria counts, protease and amylase activities, reducing sugar and amino-type nitrogen contents, and the amounts of amino acids, organic acids, and aroma-compounds. The total aerobic bacteria counts in soybean fermented with strain I13 ($7.75{\times}10^9CFU/mL$) were the highest among all the strains analyzed. Lactic acid bacteria numbers were $2.85{\times}10^9$ to $4.35{\times}10^9CFU/mL$ in soybean fermented with isolates. Amylase and protease activities of the JSB22 sample were the highest among all sample. Reducing sugar and amino-type nitrogen contents of soybean fermented with JSB22 (1.23%, 94.52 mg%) were highest. Total amino acid content of the samples was 15.88-17.62%, and glutamic acid, aspartic acid, leucine, lysine, and arginine were the major amino acids. Lactic acid (0.82-3.65 g/100 g), oxalic acid (22.74-63.57 mg/100 g), and fumaric acid (2.88-6.33 mg/100 g) were predominant organic acids. A total of 39 volatile aroma-compounds were identified, including 2 esters, 5 ketones, 7 alcohols, 14 hydrocarbons, 2 heterocyclic compounds, 4 acids, and 5 miscellaneous compounds. These results represent useful information for the development of a starter (single or complex) and will be used for production of functional fermented soybean foods.

• Korean journal of food and cookery science
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• v.22 no.6 s.96
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• pp.774-782
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• 2006

Flavor components in fresh Codonopsis lanceolata cultivated on a wild hill were detected by headspace sampling(HSS) method and GC-MS equipped with a VB-5(5% phenylmethyl polysiloxane) column. The 167 volatile compounds that were detected, consisted of 28 terpenes and terpene alcohols, 34 hydrocarbon, 31 alcohols, 13 aldehydes and ketones, 25 esters, 6 acids, 10 ethers and 20 miscellaneous components. The ten major volatile flavor components, comprising about 58% of the total, were dl-limonene (10.2%), ${\alpha}$-guaiene (9.0%), 2,2,6-trimethyl-octane (8.6%), hexadecane (8.0%), isolongifolan-8-ol (4.2%), 2,4,4-trimethyl-1,3-pentanediol diisobutyrate (4.1%), ${\beta}$-selinene (3.9%), 2,2,3-trimethylnonane (3.6%), 3-methyl-5-propyl-nonane (3.1%), and ledene (3.1%). The unique aroma of fresh Codonopsis lanceolata described by sensory evaluation was green, earthy, camphoraceous and aldehydic. The components attributed to green or camphoraceous flavor such as 1-hexanol, 2-methylhexan-3-ol, 3-hexen-1-ol, cis-3-hexenyl butyrate, ethylhexanol, hexyl acetate, trans-2-hexen-1-ol, camphor, longiborneol and menthol were not included in the ten or twenty major volatile components which had the largest peak area in descending order. We concluded that the intensity of green and camphoraceous flavor might be used as an indicator of the freshness of Codonopsis lanceolata.