• Journal of the Korean Society of Tobacco Science
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• v.25 no.1
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• pp.70-79
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• 2003

$\beta$ -Glucosidase-catalysed synthesis of glucosides with aromatic alcohols and monoterpene alcohols as accepters and cellobiose as a donor in the presence of various commercial $\beta$ -glucosidases were described. $\beta$ -Glucosidases from Aspergillus niger spp,. Trichoderma spp., Penicillium sup. and bitter almond have been shown to catalyze synthesis of $\beta$ -glucosides of benzyl alcohol, 2-hydroxybenzyl alcohol, 4-hydroxybenzyl alcohol, 2-phenylethyl alcohol, geraniol and citronellol in the presence of cellobiose as sugar donor. Among enzyme preparations tested, each $\beta$ -glucosides prepared from Aspergillus niger were isolated in the pure state by Diaion HP-20 and silica gel column chromatography. The products were identified as $\beta$ -glucosyl products of benzyl alcohol, 2-hydroxyhenzyl alcohol, 4-hydroxybenzyl alcohol, 2-phenyl ethyl alcohol, geraniol and citronellol by spectrometry (UV, IR, $^1$H-NMR, $^{13}$ C-NMR) and enzymatic hydrolysis with $\beta$ - glucosidase. Monoterpene alcohols with a sterically hindered hydroxyl group, such as linalool, $\ell$-menthol and $\alpha$-terpineol were not used as acceptors in transglycosylation reaction.

• The Korean Journal of Food And Nutrition
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• v.30 no.1
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• pp.120-128
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• 2017

This study aimed to provide volatile flavor compounds of three onion products through thermal process and alcohol fermentation, to meet the quality standard of onion products. The identified components of onion extracts (OE) included 49 (18 sulfur-containing compounds, 5 alcohols, 8 acids, 3 ketones, 4 esters, 4 aromatic compounds, 2 aldehydes, 1 pyrazines and 4 miscellaneous compounds), and 55 (17 sulfur-containing compounds, 15 alcohols, 5 acids, 11 ketones, 3 aromatic compounds, 2 aldehydes and 1 pyrazine) in autoclave-sterilized onion extracts (SOE); and 69 (10 sulfur-containing compounds, 27 alcohols, 11 acids, 11 ketones, 6 esters, 1 aromatic compound and 3 pyrazines) in onion wine (OW), respectively. Among the major flavor classes, sulfur-containing compounds (36.8%), acids (31.3%) and aldehydes (13.6%) in OE were changed to alcohols (46.5%) and ketones (27.3%) in SOE whereas, alcohols (56.3%) and acids (26.6%) in OW. Moreover, 1,3-butanediol, 2,3-butanediol, and 3-hydroxy-2-butanone were highly detected in SOE whereas, acetic acid, 3-methylbutanol, 2-phenylethanol and 1,2,3-propanetriol in OW.

• Fire Science and Engineering
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• v.7 no.2
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• pp.24-28
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• 1993

The flash point for flammable liquids (alcohol, aromatic compounds) were measured by Penskt-Martens's measuring apparatus with closed cup. As a result, it was observed that the flash points had the regular tendency according to the carbon number and the molecular structure. Consequently, the flash point for the alcohols were increased in proportion to the increase of the carbon number and branch number. The differences between the literature and experimental data are 14.6% for the relative error and 3.46$^{\circ}C$ in average for the measuring temperature.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.2
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• pp.299-304
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• 1999

To compare the composition of volatile flavor components of two different types of rice, the volatile flavor concentrates isolated from brown rices Hyangnambyeo(aromatic cultivar) and Dongjinbyeo (normal cultivar) were analyzed by gas chromatography and gas chromatography mass spectrometry. A total of components, including 16 hydrocarbons, 16 aldehydes and ketones, 15 alcohols, 4 acids, and 10 miscellaneous components were identified positively or tentat ively. Among them, n pentanol was the most abundant component in both samples and Hyangnambyeo contained more aldehydes and alcohols than Dongjinbyeo. 2 Acetyl 1 pyrroline which is chiefly responsible for the character istic odor of aromatic type rice was high in Hyangnambyeo compare to Dongjinbyeo, but these were detected as minor component.

• Bulletin of the Korean Chemical Society
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• v.3 no.4
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• pp.149-152
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• 1982

A new convenient method for the reduction of carboxylic acids to the corresponding alcohols via acyloxyborohydrides was explored. Acyloxyborohydrides, prepared from the reaction of various carboxylic acids and sodium borohydride, underwent reduction to the corresponding alcohols readily by the addition of dimethyl sulfate or Lewis acids, such as boron trifluoride etherate and triphenyl borate, presumably through acyloxyboranes. By utilizing this procedure, aliphatic and aromatic acids are rapidly and quantitatively reduced to the corresponding alcohols in terahydrofuran either at room temperature (or at $65^{\circ}$). This procedure provides selective reduction of carboxylic acids in the presence of halogen, nitro, and heterocyclic rings such as furan and thiophene.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.3
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• pp.181-185
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• 1999

To compare the composition of volatile flavor components of three different cultivars of rice, Hyangnambyeo (aromatic cultivar), Heugjinjubyeo (pigmented cultivar) and Dongjinbyeo (normal cultivar), the volatile flavor components of brown rice were isolated by Likens-Nickerson simultaneous steam distillation and extraction apparatus. The flavor concentrates obtained were analyzed by gas chromatography and gas chromatography-mass spectrometry. A total of 65 components, including 14 aliphatic aldehydes and ketones, 7 aliphatic alcohols, 8 aromatic alcohols, 13 hydrocarbons, 9 esters, 7 aliphatic acids, and 7 miscellaneous components were identified. The aliphatic aldehydes, which are known as contributors to the overall flavor of cooked rice, were present in larger amounts in Hyangnambyeo than in Heugjinjubyeo and Dongjinbyeo, while the difference in quantity of these components between Heugjinjubyeo and Dongjinbyeo was not remarkable. Hyangnambyeo and Heugjinjubeyo contained 562 ng and 259 ng of 2-acetyl-1-pyrroline per gram of brown rice based on dry weight, respectively, which is a key compound contributing to the popcorn-like aroma in aromatic rice. Dongjinbeyo contained about 6 ng.

• Bulletin of the Korean Chemical Society
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• v.31 no.8
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• pp.2361-2367
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• 2010

$TiO_2-ZrO_2$ was prepared with surfactant through a sol-gel method. Catalysts containing 5 - 35% $H_3PO_4$ were prepared using these oxides. Subsequently the catalytic performance of prepared catalysts was determined for liquid phase esterification of aromatic acids. $H_3PO_4/TiO_2-ZrO_2$ has been used as catalyst to synthesize various novel esters by esterification of some aromatic acids with aliphatic alcohols (2-propanol, 1-butanol, iso butanol, 3-pentanol, 1-hexanol, heptanol, cyclo heptanol, octanol and decanol). Under optimized conditions, maximum yields and selectivity (100%) to the corresponding ester, was obtained by using 25 wt % $H_3PO_4/TiO_2-ZrO_2$ as catalyst. The Catalyst can be easily recycled after reaction and can be reused without any significant loss of activity/selectivity performance. No by-product formation, high yields, short reaction times, mild reaction conditions, operational simplicity with reusability of the catalyst are the salient features of the present synthetic protocol. The reaction was carried out under solvent-free condition.

• Journal of Life Science
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• v.18 no.11
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• pp.1570-1577
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• 2008

For useful basic data in developing of Omandungi (Styela plicata) processed products, volatile flavor compounds were analyzed to identify the key reaction flavor compounds induced through heat treatment ($100^{\circ}C$, 10 min) in Omandungi -Doenjang (soybean paste) soups and stew. A total of 128 flavor compounds were identified and composed mainly of esters (16), aromatic compounds (14), N-containing compounds (11), alcohols (34), terpenes (5), carbonyl compounds (23), furans (4), hydrocarbons (13), acids (5) and miscellaneous compounds (3). Three groups including aromatic compounds, alcohols and acids were detected in high amounts in Doenjang. However, the levels of C4-C6 series acids (i.e., pentanoic acid having off-flavor) decreased by cooking ($100^{\circ}C$, 10 min), whereas that of furans (i.e., furfural) as heat induced compounds increased 2 times. Alcohols were detected the major group in Omandungi and followed by hydrocarbons and aromatic compounds in that order. In particular, 3 compounds including decenol, 2,6-dimethylheptanol and octanol were the major alcohols of Omandungi. By cooking, the compounds known heat-induced compound, 2-acetyl-2-thiazoline and benzothiazole, were newly formed in Omandungi-Doenjang stew. The alcohols (i.e., decenol, 2,6-dimethylheptanol), hydrocarbons and aromatic compounds derived from Omandungi were supposed to enhance a seafood-like flavor in Omandungi-Doenjang stew.

• Korean journal of food and cookery science
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• v.17 no.1
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• pp.55-59
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• 2001

To investigate the usefulness of Allium senescens as a aromatic edible plant, volatile flavor components and flavor pattern were analyzed. Essential oils of fresh and freeze dried Allium senescens were extracted by SDE(simultaneous steam distillation and extraction) method using diethyl ether as solvent. And their volatile flavor components were analyzed by gas chromatography(GC) and gas chromatography-mass spectrometry (GC-MS). A total of 46 components, including 11 hydrocarbons, 9 aldehydes, 4 alcohols, 2 esters, 7 acids, 4 ketones and 9 sulfur containing compounds were identified in fresh Allium senescens. In freeze dried Allium senescens, 8 hydrocarbons, 5 aldehydes, 3 alcohols, 5 esters, 2 acids, 3 ketones and 4 sulfur containing compounds were identified. Volatile flavor patterns of Chinese chive and Allium senescens were compared using electronic nose. The score of first principal component was significantly different in Allium senescens and Chinese chive.

• Bulletin of the Korean Chemical Society
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• v.34 no.11
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• pp.3410-3414
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• 2013

Atom-economical esterification is of great importance in green chemistry. In this work, we demonstrated the catalyst and additive free esterification of alcohols by their reaction with 2-acyl-4,5-dichloropyridazin-3(2H)-ones without solvent at $100^{\circ}C$. Aliphatic and aromatic alcohols were converted into the corresponding esters in good to excellent yields. It is noteworthy that the reaction is solvent-free, atom-economic, easy-workup, and rapid and that the process is inexpensive.