• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.6
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• pp.801-805
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• 2003

Volatile flavor components in chestnut (Castanea crenate Sieb. et Zucc.) flower were collected by SDE method using the mixture of n-pentane and diethylether as an extract solvent and were identified by GC-FID and GC/MS. A total of 122 components including 35 alcohols,5 hydrocarbons,20 terpene and derivatives,7 ketones, 24 aldehydes, 12 esters, 4 acids, 3 furans, and 2 miscellaneous were identified from total volatile extract of chestnut. Alcohols were comprise 36.58% of volatile extract and dominant constituents and the main components of flower volatiles were 1-phenylethanol (18.6%), (E)-geraniol, tricosane, heneicosane, benzyl alcohol, acetophenone and 2-phenylethanol as aromatic alcohols and odd carbon hydrocarbons. Especially 1-phenylethanol and acetophenone would be applicable to the markers to ascertain floral origin of chestnut honey. The powerful animal and floral notes of chestnut flower were characterized by compounds including nonanal.

• Journal of the Korean Applied Science and Technology
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• v.38 no.1
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• pp.99-106
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• 2021

To circumvent the skin problem from phenylethanol (PhE), we have studied on the enzymatic synthesis of phenylethanol galactoside (PhE-gal) as an alternative to PhE. Base on the previous study, we optimized the reaction conditions for PhE-gal synthesis from PhE using E. coli β-galactosidase (β-gal). The optimal amount of β-gal, PhE concentration, pH, and temperature for PhE-gal synthesis were 0.45 U/ml, 1%, 8.0, 40℃, respectively. Under these conditions, about 81.9 mM PhE was converted into about 47.4 mM PhE-gal, in which the conversion yield was about 57.9%. Meanwhile, when the reaction mixture containing PhE and PhE-gal was mixed and fractionated with water-immiscible solvent (EA or MC), it was observed that PhE-gal was distributed in water phase, and PhE was distributed in solvent phase. Additionally, PhE-gal was clearly distributed into water phase when MC was used, but PE-gal was not when EA was used. In the future, we are planning to carried out the continuing study on developing an alternative cosmetic preservative using PhE-gal.

• Bulletin of the Korean Chemical Society
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• v.32 no.4
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• pp.1327-1330
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• 2011

Dehydration of 1-phenylethanol to produce styrene has been studied in liquid phase with three solid acid catalysts such as H-ZSM-5, H-Y and Amberlyst-15. Amberlyst-15 shows the highest conversion and styrene yield, suggesting the applicability of a resin catalyst in the dehydration. The good performance of the Amberlyst-15 may be due to high acid concentration and ready diffusion of reactants and products. A possible reaction scheme (such as the formation of styrene from diphenylethylether) has also been suggested.

• Microbiology and Biotechnology Letters
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• v.48 no.1
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• pp.90-97
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• 2020

Vinegar was prepared from corn produced in Gangwon province and changes to the major aroma components were investigated for acetic acid fermentation and ripening. The most prevalent volatile component in corn alcohol was determined to be 2-phenylethanol (accounting for 27% of total aroma components); the levels of 2-phenylethanol decreased to 15% after acetic acid fermentation. Principal component analysis of volatile compounds revealed that corn vinegar was distinguishable from corn alcohol. The highest content of total volatile components (50%) was acetic acid, followed by 2-phenylethanol and diethyl succinate. Ethyl phenylacetate and diethyl succinate had the highest odor activity value, and might contribute most profoundly to the aroma of corn vinegar.

• Korean Journal of Food Science and Technology
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• v.48 no.2
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• pp.122-127
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• 2016

The objective of this study was to identify the volatile compounds and aroma-active compounds from acai berry (Euterpe oleracea). Volatiles were isolated by high vacuum distillation using solvent-assisted flavor evaporation (SAFE) and liquid-liquid continuous extraction (LLCE). To identify the characteristic aroma-active compounds of acai berry, gas chromatography-mass spectrometry-olfactometry was used. Aroma-active compounds were evaluated by aroma extract dilution analysis (AEDA). A total of 51 and 54 volatile compounds from acai berry were identified from SAFE and LLCE extracts, respectively. Alcohols were confirmed to be important volatile compounds in acai berry, as the major volatile compounds were 2-phenylethanol, (Z)-3-hexenol, and benzyl alcohol. ${\beta}-Damascenone$ (berry, rose), trans-linalool oxide (woody), (Z)-3-hexenol (grass), and 2-phenylethanol (rose, honey) were considered the aroma-active compounds in acai berry. The most intense aroma-active compound of acai berry was ${\beta}-damascenone$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.12
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• pp.1755-1761
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• 2016

Volatile flavor compounds in soy sauce residue (SSR) and acid hydrolysate of SSR (AHSSR) were analyzed by solid phase micro extraction (SPME)/gas chromatography (GC)/mass spectrometry (MSD) methods. A total of 79 compounds were detected in samples (66 SSR and 60 AHSSR). Quantitatively, alcohols (433.37 ng/g), aldehydes (273.01 ng/g), esters (236.80 ng/g), and aromatic hydrocarbons (180.66 ng/g) were dominant in the volatiles of SSR, whereas furans (249.27 ng/g) were only dominant in AHSSR (P<0.05). Among these, four esters, 3-methylbutyl acetate (banana/pear-like), ethyl 3-methyl butanoate (fruity), ethylbenzene acetate (wine-like), and ethyl 3-methyl butanoate (apple-like), three alcohols, 3-methyl-1-butanol (fruity/whisky-like), 2-phenylethanol (floral/sweet), and 1-octen-3-ol (mushroom-like), four aldehydes, (E)-2-phenyl-2-butenal (chocolate-like), benzaldehyde (almond-like), 3-methylbutanal (malty), and 2-phenylacetaldehyde (floral), four aromatic hydrocarbons, 4-ethyl-2-methoxyphenol (smoky/soy sauce-like), 4-ethylphenol (medicine-like), 4-vinyl-2-methoxyphenol (woody), and phenol (woody), and two furans, furfural (almond-like) and 4-hydroxy-2,5-dimethyl-3(2H)-furanone (caramel-like), were major compounds in SSR, whereas seven compounds, including furfural, 5-methylfurfural (almond-like), 3-methyl-1-butanol, 2-phenylethanol, 4-ethyl-2-methoxyphenol, 3-methylbutanal, and benzaldehyde were major compounds in AHSSR.

• Journal of the Korean Applied Science and Technology
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• v.37 no.5
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• pp.1323-1329
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• 2020

To characterize the molecular structure of PhE-gal synthesized using Escherichia coli 𝛽-gal, NMR (¹H- and ¹³C-) spectroscopy and mass spectrometry of PhE-gal were conducted. ¹H NMR spectrum of PhE-gal showed multiple peaks corresponding to the galactosyl group, which is an evidence of galactosylation on 2-phenylethanol (PhE). Downfield proton peaks at 𝛿_H 7.30~7.21 ppm showed the presence of aromatic protons of PhE as well as benzyl CH₂ protons at 𝛿_H 2.88 ppm. Up field proton peaks at 𝛿_H 4.31 ppm, 4.07 ppm and multiple peaks from 𝛿_H 3.86~3.38 ppm are indicative of galactocylation on PhE. ¹³C NMR spectrum revealed the presence of 12 carbons suggestive of PhE-gal. Among 12 carbon peaks from PhE-gal, the four peaks at 138.7, 129.0, 128.6 and 126.5 were assigned aromatic carbons in the phenyl ring. Three peaks at 129.0, 128.6 and 126.5 showed high intensities, indicating CH aromatic carbons. ¹³C NMR data of PhE-gal showed 6 monosaccharide peaks from galactose and 2 peaks from aliphatic chain of PhE, indicating that PhE-gal was galactosyl PhE. The mass value (sodium adduct ion of PhE-gal, m/z = 307.1181) from mass spectrometry analysis of PhE-gal, and ¹H and ¹³C NMR spectral data were in good agreement with the expecting structure of PhE-gal. We are expecting that through future study it will eventually be able to develop a new additive with low cytotoxicity.

• Korean Journal of Food Science and Technology
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• v.31 no.1
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• pp.36-44
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• 1999

Samjangs which were prepared using magjang, traditional doenjang, and mixture of traditional doenjang and magjang were stored. Characteristics of the stored samjangs were investigated. Maximum titratable acidity was shown in traditional doenjang after 30 day of storage. Total sugar in samjangs decreased while reducing sugar increased to $11.45{\sim}12.35%$ from $8.44{\sim}9.29%$ after 40 days. Amino type nitrogen predominantly increased to $337.3{\sim}381.1\;mg%$ after 40 days from $48{\sim}53\;mg%$ of initial period of preparation. Among the free amino acids the content of glutamic acid $(202.6{\sim}464.6\;mg/100g)$ was highest and others were not too much changed. Forty two components including 7 alcohols, 4 esters, 13 acids, 6 aldehydes, 5 phenols, 3 pyrazines and others were found in samjangs. Ethanol, acetic acid ethyl ester and 2-phenylethanol were found in all treatments and ethanol, acetic acid ethyl ester, phenylacetaldehyde, butanoic acid, acetic acid, 3-methyl butanoic acid and 2,4-hexadienoic acid might be major volatile components considering of high peak area. 2-Phenylethanol, butandioic acid ethyl ester, butanoic acid and 2-methyl-2-butenoic acid were higher than other components in samjang with magjang while ethanol, acetic acid, 2,4-hexadienoic acid were in samjang with traditional doenjang and 3-methyl butanoic acid, acetic acid ethyl ester and methyl pentanoic acid were in the mixed treatment.

• Journal of Microbiology and Biotechnology
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• v.26 no.1
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• pp.72-79
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• 2016

The fungal morphologies and pellet sizes were controlled in acetophenone reduction by Rhizopus oryzae. The acetophenone conversion and (S)-phenylethanol enantiomeric excesses (e.e.) reached the peak after 72 h of incubation when using pellets with 0.54 mm diameter, which showed an excellent performance compared with suspended mycelia, clumps, and pellets with 0.65 or 0.75 mm diameter. Furthermore, nano-sized acetophenone was used as a substrate to improve the performances of biotransformation work. The results showed that the conversion of nanometric acetophenone and (S)-phenylethanol e.e. reached the maximum (both >99%) after 32 h of incubation when using 0.54 mm diameter pellets, at least 24 h in advance of the control group. On the other hand, Tween 80 and 1, 2-propylene glycol showed low or no toxicity to cells. In conclusion, pellets and acetophenone nanoemulsions synergistically result in superior performances of acetophenone reduction.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2020.08a
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• pp.110-110
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• 2020

꽃을 우려내어 차로 마시는 꽃차(flower tea)는 꽃이 가진 색과 향, 맛과 모양을 즐길 수 있어 최근 수요가 급증하고 있다. 본 연구는 매화(Prunus mume), 장미(Rosa spp.), 그리고 해당화(Rosa rugosa) 등 3종의 장미과 식물의 꽃차의 향기 성분 특성을 구명코자 꽃차를 headspace vial에 담은 후 solid phase microextraction(SPME)를 이용하여 추출한 후 gas chromatography-mass spectrometry를 이용하여 휘발성 성분을 분리하였다. 분리된 각 성분은 deconvolution 과정을 수행한 후 NIST masss spectral library를 이용하여 동정하였다. 매화꽃차에서는 총 58개의 휘발성 성분이 검출되었는데, benzaldehye와 nonane, 그리고 phenylmethanol이 주요 구성 성분으로 검출된 전체 휘발성 성분의 각각 64.7%, 16.1% 및 4.7%를 차지하고 있었다. 장미 꽃차의 경우 검출된 35종 중 주요 구성 성분은 nonane과 2-phenylethanol, 그리고 phenylmethanol로서 각각 전체 성분 중 54.0%, 18.0% 및 4.6%를 구성하고 있었다. 해당화 꽃차의 경우는 장미 꽃차와 동일하게 2-phenylethanol(62.2%)과 nonane(20.1%)이 주요 성분으로 동정되었으며 이들 2 성분의 합이 전체 43개 휘발성 성분의 82.3%를 차지하는 것으로 나타났다. 본 연구에 사용된 매화, 장미, 해당화 등 장미과 식물 3종의 꽃차 모두에서 공통적으로 검출된 휘발성 성분은 앞서 각 꽃차 종류별 주요 성분으로 언급된 4종의 성분을 포함하여 19종이었으며 매화꽃차에서만 검출된 성분은 29종으로 장미꽃차(6종)와 해당화 꽃차(8종)보다 향기성분의 다양성이 높은 것으로 나타났다.