• Applied Biological Chemistry
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• v.27 no.1
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• pp.14-20
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• 1984

Volatiles from Mallus pumila Miller Var. Fuji, Ralls Janet and Jonathan during maturity were examined. The volatiles of apples were collected by the headspace trapping method using. Tenax GC and identified by gas liquid chromatography and GC-mass spectrometry. Among over 34 GLC peaks, 23 esters, 9 alcohols and 2 aldehydes were identified. The quantity of volatiles produced was increased in proportion to the degree of maturity, and 1-butanol, isobutyl butyrate, 2-pentanol, ethyl valerate and hexanal were major.

• Food Engineering Progress
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• v.13 no.3
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• pp.190-194
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• 2009

The aim of this study was to investigate the change of volatile aroma compounds in kimchi during fermentation, before and after drying process. Also, the encapsulation effect of cyclodextrin on volatiles during the drying process was examined. GC-MS was used for detection and identification of volatile compounds. During kimchi fermentation, in the early stage, dimethyl sulfide, carbon disulfide were detected as major compounds and after 7 days several sulfur compounds, dimethyl disulfide, methyl 2-propenyl disulfide, allyl methyl sulfide, and di-2-propenyl disulfide bacame the major volatiles. After vacuum-drying, the kimchi powder lost 11 compounds but still retained 13 volatiles of which major compounds were dimethyl sulfide, acetaldehyde and methanethiol. In order to keep volatiles in kimchi powder along with the drying process, 0.25-1.0% cyclodextrin was added in kimchi and dried-kimchi was prepared by using vacuum dryer. Cyclodextrin acted as an encapsulation agent for aroma compounds and it resulted in less loss of volatiles during drying process. Addition of cyclodextrin will permit industry-scale production of dried-kimchi powder with less loss of aroma compounds.

• Journal of the Korean Wood Science and Technology
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• v.48 no.4
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• pp.503-512
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• 2020

Using Na₂CO₃ versus NaCl as chemical activator, we compared the quality of activated carbon produced from oil palm fronds as raw material. These activators were selected for comparison because both are readily available and are environmentally friendly. In the manufacturing, we used Indonesian National Standard (SNI 06-3730-1995) parameters. For the quality comparison, we determined activated-carbon yield, moisture, ash, volatiles, and fixed-carbon contents; and adsorption capacity of iodine. The best characteristics, assessed by morphological surface analysis and Fourier transform infrared (FTIR) spectral analysis, were observed in the carbon activated by Na₂CO₃ at an activator concentration of 10% and carbonization temperature of 400 ℃. The results were as follows: activated-carbon yield, 84%; water content, 8.80%; ash content, 2.20%; volatiles content, 14.80%; fixed-carbon content, 68.60%; and adsorption capacity of iodine, 888.51 mg/g. Identification using the FTIR spectrophotometer showed the presence of the functional groups O-H, C=O, C=C, C-C, and C-H in the Na₂CO₃-activated carbon.

• Korean Journal of Food Science and Technology
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• v.37 no.6
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• pp.1048-1064
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• 2005

Detection of specific compounds influencing food flavor quality is not easy. Electronic nose, comprised of electronic chemical sensors with partial specificity and appropriate pattern recognition system, is capable of recognizing simple and complex volatiles. It provides fast analysis with simple and straightforward results and is best suited for quality control and process monitoring of flavor in food industry. This review examines application of electronic nose in food analysis with brief explanation of its principle. Characteristics of different sensors and sensor drift. and solutions to related problems are reviewed. Applications of electronic nose in food industry include monitoring of fermentation process and lipid oxidation, prediction of shelf life, identification of irradiated volatile compounds, discrimination of food material origin, and quality control of food and processing by principal component analysis and neural network analysis. Electronic nose could be useful for quality control in food industry when correlating analytical instrumental data with sensory evaluation results.

• Korean journal of applied entomology
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• v.61 no.1
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• pp.35-50
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• 2022

In this review, the compositions of the sex pheromones of 22 lepidopteran species were analyzed and briefly arranged by comparing the research results conducted in different locations worldwide. These compositions can be used as monitoring tools for pests of rice, maize, leguminous crops, perilla, and sesame in Korea. The sex pheromone compounds and those compositions of four species were successfully identified within Korean populations. The optimal compositions of sex pheromones of three other species were selected through behavioral studies using synthetic chemicals of the known pheromone compounds in laboratories and fields, without chemical identification processes in the sex pheromone compounds of Korean populations. For a few species, the roles of the minor components of the sex pheromone volatiles should be re-assessed for use in the development of optimal monitoring lures.

• Journal of the Korean Society of Food Science and Nutrition
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• v.17 no.1
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• pp.1-5
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• 1988

Kochujang (Red pepper paste) is one of a traditional fermented seasoning foods having peculia. flavor. In present paper, the effects of microorganisms on the formation of volatile components of Kochujang during fermentation were observed. The volatiles of Kochujang were extracted by a steam-distillation under the reduced pressure and determined by gas chromatography and gas chromatography-mass spectrometry (CC-MS), respectively. During fermentation of Kochujang, Saccharomyces sp. and three strains of Bacillus sp. were isolated as main microorganisms participating in the formation of volatile components. According to the analytical results, tetrahydro geroniol, furfuryl alcohol, methoxy acecoptenone and myrtanal in Kochujang inoculated with Saccharomyces spl, 2-methyl-propan-2-ol, furfuryl alcohol an furfuryl-n-butyrate in Kochujang inoculated with Bacillus sp. B-1, 2-methyl-propan-2-ol, furfuryl alcohol and furfuryl-n-butyrate in Kochujang inoculated with Bacillus sp. B-2, and 2-methyl-propan-2-ol, furfuryl alcohol and n-propylbenzene in Kochujang inculated with Bacillus sp. B-3, were identified as major components, respectively.

• Applied Biological Chemistry
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• v.31 no.3
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• pp.292-297
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• 1988

The volatiles of whole and homogenated tomato fruits collected by the headspace trapping method using Tenax GC and the simultaneous steam distillation method were identified by GC and GC-MS. Among over 100 GC peaks, 10 alcohols, 6 aldehydes, 4 ketones, 3 esters, 1 phenol and 1 acid were identified from whole tomato fruits, whereas 12 alcohols, 6 aldehydes, 5 ketones, 5 esters, 2 phenols, 1 hydrocarbon and 1 acid were identified from homogenated tomato fruits. By simultaneous steam distillation-extraction, 19 alcohols, 13 hydrocarbons, 9 esters, 9 ketones, 8 aldehydes, 2 phenols, 2 lactones,2 furans, 1 acids and 2 others were identified among over 300 peaks.

• Korean Journal of Food Science and Technology
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• v.20 no.5
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• pp.718-723
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• 1988

A yeast strain producing fruity-floral aroma was isolated from soil and identified as Hansenula saturnus var. saturnus. Glucose was found to be the best carbon source and sodium nitrate or phenylalanine as nitrogen source in terms of the nature and the intensity of the aroma produced by the isolated yeast. Seventeen compounds, mainly esters and alcohols, were identified in the ether-pentane extract of the culture broth by gas chromatography and/or coupled gas chromatography-mass spectrometry. Ethyl alcohol, isobutyl alcohol, isoamyl alcohol, phenethyl alcohol and their acetate esters together with ethyl caprylate were the major compounds in the aroma concentrate. Three unusual compounds, dibutyl disulfide, 3-methyl pentanoic acid and methyl pentanoate were also tentatively identified in the culture broth of the isolated yeast.

• 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.

• Korean Journal of Food Science and Technology
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• v.7 no.1
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• pp.15-21
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• 1975

Soong-Neung is a Korean traditional beverage served after meals and is made from cooked and roasted rice produced on the bottom of the container during the rice cooking process. The volatiles from the extract of cooked and roasted rice were separated into pyrazine and carbonyl fractions and qualitatively investigated. The pyrazine fraction was characterized by gas chromatography and combined gas chromatography-mass spectrometry and five pyrazines were positively identified. Pyrazine compounds identified are 2-methylpyrazine, 2,3-dimethylpyrazine, 2,5-dimethylpyrazine, 2-ethyl-5-methylpyrazine and 2-ethyl-3-methylpyrazine. Carbonyls were converted to their 2,4-dinitrophenylhydrazones and identified by gas chromatography, combined gas chromatography-mass spectrometry and thin layer chromatography. Acetaldehyde, propionaldehyde, iso-butyraldehyde and iso-valeraldehyde were positively identified in the carbonyl compounds. The aroma of the fractions indentified as 2,3-dimethylpyrazine and 2,5-dimethylpyrazine had a nut-like or roasted cereal-like flavor, which is one of the characteristic flavors of Soong-Neung.