• The Korean Journal of Food And Nutrition
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• v.31 no.6
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• pp.890-896
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• 2018

The aim of this study was to determine volatile flavor compounds in Shingo pear juice. Volatile flavor compounds were analyzed using solid-phase micro-extraction (SPME) - gas chromatography-mass spectrometry (GC-MS). The effect of inorganic salts solution on the extraction ability of the SPME fiber was treated by adding saturated $CaCl_2$ solution at the ratio of 1:20 (v/v) after 0, 60, 120 min of preparing pear juice, respectively. As a result, a total of 22 volatile compounds were identified in Shingo pear juice. Ethyl acetate was found to be the most abundant volatile compound ($13.36{\sim}19.61{\mu}g/kg$), followed in order by hexanal, ethyl hexanoate, ethyl 3-(methylthio)-2-propenoate, ethyl octanoate and 2-hexenal. Total contents of volatile flavor compounds were $31.07{\mu}g/kg$ (control), $40.93{\mu}g/kg$ (0 min), $27.62{\mu}g/kg$ (60 min) and $26.32{\mu}g/kg$ (120 min). This result indicated that the addition of saline solutions could inhibit the enzymatic reaction of volatile flavor compounds effectively when treated as soon as juice preparation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.5
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• pp.775-783
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• 2015

This study was carried out to investigate the physicochemical properties and volatile ingredients of Jeju Apple mango subjected to different extraction methods and GC/MS. The crude protein, fat, and ash contents were $0.22{\pm}0.01$, $0.09{\pm}0.00$, and $0.27{\pm}0.02%$, respectively, and contents of free sugar increased in the order of sucrose, fructose, and glucose, whereas maltose, lactose, and galactose were not detected. The numbers of volatile flavor compounds obtained by the SE (solvent extraction), SDE (simultaneous steam distillation extraction), and SPME (solid-phase micro-extraction) methods were 51, 59, and 71, respectively. The percentages of extracted volatile flavor compounds in mango were 11.44, 15.68, and 73.54% by the SE, SDE, and SPME methods, respectively. The most abundant compounds found in Jeju Apple mango were terpenes and their derivatives, which accounted for 44.49~94.57% of total volatiles obtained. SPME method was considered to be the most effective extraction method in terms of the numbers of detected compounds and their amounts. ${\delta}$-3-Carene was identified as the dominant compound in mango, whereas ${\alpha}$-phellandrene, ${\gamma}$-terpinene, trans-${\beta}$-ocimene, ${\alpha}$-terpinolene, limonene, ${\alpha}$-pinene, and furaneol were the next important compounds.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.7
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• pp.874-880
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• 2007

Volatile flavor compounds of 4 grape species (Campbell, Sheridan, Red globe, and Meoru) were identified during 3-day storage at either $4^{\circ}C$ or room temperature. Each sample was analyzed by solid-phase micro-extraction (SPME) method combined with gas chromatography-mass spectrometry. Also electronic nose composed of 12 different metal oxide sensors was used to differentiate flavors of grapes. Sensitivities (delta $R_{gas}/R_{air}$) of sensors from electronic nose were obtained by principal component analysis (PCA). Proportion of the first principal component was 99.30% at $4^{\circ}C$ and 99.36% at room temperature, respectively. In our result, flavor patterns of grape can be differentiated according to the storage period. The major volatile flavor compounds were 1-hexanol, hexanoic acid and its ethyl ester, and phenylethyl alcohol with the presence of butanoic acid and its ethyl ester, acetic acid, benzeneacetic acid and its ethyl ester.

• Food Science and Biotechnology
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• v.16 no.1
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• pp.37-42
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• 2007

The biotransformation of monoterpenic agro-industrial wastes (turpentine oil and essential orange oil) was studied. More than 40 fungal strains were isolated from Brazilian tropical fruits and eucalyptus trees and screened for biotransformation of the waste substrates. Solid phase microextraction was used to monitor the presence of volatile compounds in the headspaces of sporulated surface cultures. The selected strains were submitted to submerged liquid culture. The biotransformation of R-(+)-limonene and ${\alpha},\;{\beta}-$ pinenes from the oils resulted in ${\alpha}-terpineol$ and perillyl alcohol, and verbenol and verbenone, respectively, as the main products. The selected strains were also placed in contact with ${\alpha}-$ and ${\beta}-$ pinenes standards. It was confirmed that verbenol, verbenone, and ${\alpha}-terpineol$ were biotransformation products from the terpenes. A concentration of 90 mg/L of verbenone was achieved by Penicillium sp. 2360 after 3 days of biotransformation.

• Analytical Science and Technology
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• v.25 no.1
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• pp.39-49
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• 2012

A method to detect 37 volatile organic compounds (VOCs) in surface water was described based on headspace solid-phase micro extraction and gas chromatography-mass spectrometry. VOCs in water were vaporized for 30 min at 40 $^{\circ}C$ in a headspace vial and adsorbed on 85 ${\mu}m$ carboxen-polydimethylsiloxane. Under the established condition, the lowest quantification limit was 4.1-96 ng/L by using 4.0 mL water sample, and the relative standard deviation was less than 15% at concentrations of 0.05 and 0.50 ${\mu}g/L$. The detection limits meet lower concentration than 1/10 of the water quality criteria for VOCs established by the US EPA or Germany. The LOQ is a sensitivity which the monitoring for the establishing water quality criteria requires. When the proposed method was used to analyze the target compounds in sixteen surface water samples and total 16 VOCs were detected in surface water samples collected from Gum-River. Maximum concentrations of VOCs detected were not exceeded the EPA or Germany guidelines in any of the samples.

• Korean Journal of Food Science and Technology
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• v.39 no.6
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• pp.658-662
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• 2007

In this study, wild sesame leaf aromas (WSLA) were extracted and the extracted aromas were entrapped in porous potato starch micelles. The entrapped aromas did not evaporate, even by heated water treatments, and remained until a physical treatment such as chewing. Thus, the entrapped WSLA starch was used to make precooked instant noodles in order to mask or/and reduce an unpleasant raw flour flavor. The efficiencies of the flavor entrapment were analyzed using gas-chromatography equipped with solid phase micro-extraction (SPME), as well as by sensory evaluation. The highest yield of the porous potato starch was shown as 82.4% at an inlet temperature (IT) of $170^{\circ}C$, an exhaust temperature (ET) of $90^{\circ}C$, and a feeding rate (FR) of 40 mL/min. In the porous starch made by IT at $200^{\circ}C$, ET at $100^{\circ}C$, and FR at 50 mL/min, the entrapment efficiency was 68% by GC analysis; this starch also had the highest WSLA and consumer acceptability, but the lowest raw flour flavor, according to the sensory evaluation results.

• Analytical Science and Technology
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• v.13 no.6
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• pp.736-742
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• 2000

The purpose of this study was to determine the homocysteine (Hey), methionine (Met) and cysteine (Cys) using solid phase micro-extraction (SPME)/gas chromatography (GC)-mass spectrometry (MS) in human plasma and to correlate between the plasma concentration of homocysteine with coronary artery disease. The homocysteine, methionine and cysteine in blood can be used as biomarkers for the risk assessment of vascular disease. The plasma homocysteine level for the coronary artery disease patients was higher than general patients. The concentration ranges of the Hcy, Met and Cys for coronary artery disease patients were $18.47-33.38{\mu}mol/L$, $30.16-55.72{\mu}mol/L$ and $183.16-387.32{\mu}mol/L$, respectively. This method showed good sensitivity and convenience.

• Analytical Science and Technology
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• v.33 no.1
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• pp.11-22
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• 2020

When extracting semi-volatile components of herbal medicines using hot water vapor, some substances may react with water vapor or oxygen, and some volatile substances may be lost, when using an organic solvent extraction method has the disadvantage that it may contain a non-volatile material and residual organic solvent. In addition, it is inefficient to separate semi-volatile substances from herbal medicines into each single component and conduct biological activity research for each component to determine the effective ingredient, and some components may be lost in the separation process. In this study, semi-volatile substances evaporated under two pressure-reduced conditions in Chinese herbal medicines such as Cnidii Rhizoma, Aucklandiae Radix and Amomum Fructus were separated by cooling with liquid nitrogen. Those were analyzed by gas chromatography-mass spectrometry (GC-MS) to identify the components, and this method may be used to study biological activities at the cellular level. The substances separated under reduced pressure, essential oil obtained by simultaneous distillation extraction (SDE) method and substances by using solid phase micro-extraction (SPME) from Cnidii Rhizoma, Aucklandiae Radix and Amomum Fructus were analyzed by GC-MS. In the case of Cnidii Rhizoma and Aucklandiae Radix, there were some differences among the essential oil components obtained by SDE and those identified by low temperature capture (CT) and SPME method, these were believed to be produced by some volatiles reacting with water or oxygen at the boiling point temperature of water.

• Applied Biological Chemistry
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• v.46 no.1
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• pp.23-27
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• 2003

Lipoxygenase is the enzyme responsible for the formation of $C_6$-alcohols and $C_6$-aldehydes ($C_6$-compounds), which are well blown contributors to various types of 'green odor' In green tea. Changes in lipoxygenase activity and volatile compounds of green tea leaves were monitored daily during early growing season. The enzyme activity was spectrophotometrically measured using linoleic acid as a substrate. The volatile compounds were extracted through Solid Phase Micro-Extraction, and were subjected to GC and GC-MS analyses. Results showed that lipoxygenase activity and levels of $C_6$-compounds concomitantly increased or decreased during the early growing season, probably caused by the fluctuation in the daily temperature; increase in temperature led to the increase in enzyme activities and $C_6$-compound levels, whereas leaves plucked too early had low volatile compound levels. In this study, optimum plucking time of tea leaves for the production of high quality green tea with a wellbalanced aroma was determined.

• Journal of the Korean Society of Food Culture
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• v.22 no.2
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• pp.246-253
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• 2007

Mineral and volatile flavor compounds of Pimpinella brochycarpa N., a perennial Korean medicinal plant of the Umbelliferae family, were analyzed by inductively coupled plasma-atomic emission spectroscopy (ICP-AES) and simultaneous steam distillation extract (SDE)-gas chromatography mass spectrometry (GC/MS), head space solid phase micro-extraction (HS-SPME)-GC/MS. Mineral contents of the stalks and leaves were compared and the flavor patterns of the fresh and the shady air-dried samples were obtained by the electronic nose (EN) with 6 metal oxide sensors. Principal component analysis (PCA) was carried out using the data obtained from EN. The 1st principal values of the fresh samples have + values and the shady air-dried have - values. The essential oil extracted from the fresh and the shady air-dried by SDE method contain 58 and 31 flavor compounds. When HS-SPME method with CAR/PDMS fiber and PDMS fiber were used, 34 and 21 flavor compounds. The principal volatile components of Pimpinella brachycarpa N. were ${\alpha}$-selinene, germacrene D, and myrcene.