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Sample records for 1,1-diethoxyethane

  1. Proteins involved in wine aroma compounds metabolism by a Saccharomyces cerevisiae flor-velum yeast strain grown in two conditions.

    Science.gov (United States)

    Moreno-García, Jaime; García-Martínez, Teresa; Millán, M Carmen; Mauricio, Juan Carlos; Moreno, Juan

    2015-10-01

    A proteomic and exometabolomic study was conducted on Saccharomyces cerevisiae flor yeast strain growing under biofilm formation condition (BFC) with ethanol and glycerol as carbon sources and results were compared with those obtained under no biofilm formation condition (NBFC) containing glucose as carbon source. By using modern techniques, OFFGEL fractionator and LTQ-Orbitrap for proteome and SBSE-TD-GC-MS for metabolite analysis, we quantified 84 proteins including 33 directly involved in the metabolism of glycerol, ethanol and 17 aroma compounds. Contents in acetaldehyde, acetic acid, decanoic acid, 1,1-diethoxyethane, benzaldehyde and 2-phenethyl acetate, changed above their odor thresholds under BFC, and those of decanoic acid, ethyl octanoate, ethyl decanoate and isoamyl acetate under NBFC. Of the twenty proteins involved in the metabolism of ethanol, acetaldehyde, acetoin, 2,3-butanediol, 1,1-diethoxyethane, benzaldehyde, organic acids and ethyl esters, only Adh2p, Ald4p, Cys4p, Fas3p, Met2p and Plb1p were detected under BFC and as many Acs2p, Ald3p, Cem1p, Ilv2p, Ilv6p and Pox1p, only under NBFC. Of the eight proteins involved in glycerol metabolism, Gut2p was detected only under BFC while Pgs1p and Rhr2p were under NBFC. Finally, of the five proteins involved in the metabolism of higher alcohols, Thi3p was present under BFC, and Aro8p and Bat2p were under NBFC. PMID:26187821

  2. Proteins involved in wine aroma compounds metabolism by a Saccharomyces cerevisiae flor-velum yeast strain grown in two conditions.

    Science.gov (United States)

    Moreno-García, Jaime; García-Martínez, Teresa; Millán, M Carmen; Mauricio, Juan Carlos; Moreno, Juan

    2015-10-01

    A proteomic and exometabolomic study was conducted on Saccharomyces cerevisiae flor yeast strain growing under biofilm formation condition (BFC) with ethanol and glycerol as carbon sources and results were compared with those obtained under no biofilm formation condition (NBFC) containing glucose as carbon source. By using modern techniques, OFFGEL fractionator and LTQ-Orbitrap for proteome and SBSE-TD-GC-MS for metabolite analysis, we quantified 84 proteins including 33 directly involved in the metabolism of glycerol, ethanol and 17 aroma compounds. Contents in acetaldehyde, acetic acid, decanoic acid, 1,1-diethoxyethane, benzaldehyde and 2-phenethyl acetate, changed above their odor thresholds under BFC, and those of decanoic acid, ethyl octanoate, ethyl decanoate and isoamyl acetate under NBFC. Of the twenty proteins involved in the metabolism of ethanol, acetaldehyde, acetoin, 2,3-butanediol, 1,1-diethoxyethane, benzaldehyde, organic acids and ethyl esters, only Adh2p, Ald4p, Cys4p, Fas3p, Met2p and Plb1p were detected under BFC and as many Acs2p, Ald3p, Cem1p, Ilv2p, Ilv6p and Pox1p, only under NBFC. Of the eight proteins involved in glycerol metabolism, Gut2p was detected only under BFC while Pgs1p and Rhr2p were under NBFC. Finally, of the five proteins involved in the metabolism of higher alcohols, Thi3p was present under BFC, and Aro8p and Bat2p were under NBFC.

  3. Changes in physico-chemical and volatile aroma compound composition of Gewürztraminer wine as a result of late and ice harvest.

    Science.gov (United States)

    Lukić, Igor; Radeka, Sanja; Grozaj, Nikola; Staver, Mario; Peršurić, Đordano

    2016-04-01

    To investigate the changes in physico-chemical and aroma composition after late and ice harvest, Gewürztraminer wines were subjected to standard, enzymatic and GC/MS analysis. Late harvest (LHGW) and ice wines (IHGW) contained more sugars, extract and volatile acidity than standard wines (SGW). IHGW had elevated glycerol and gluconic acid amounts. LHGW was richer in monoterpenol oxides, β-damascenone, 1-octen-3-ol, acetates, ethyl cinnamate and 4-vinylguaiacol than SGW. IHGW contained even higher amounts, with increased citronellol, acetaldehyde, ethyl acetate, dicarboxylic acids esters, benzenoids, furans and acetals, and reduced fermentation aroma compounds. Based on odour activity values, the strongest odorants in SGW were fruity esters. In LHGW the impact of esters increased, while in IHGW cis-rose oxide, β-damascenone and 1,1-diethoxyethane emerged as the most potent. Fruity and sweet were the dominant aroma compound series in SGW and LHGW, but in IHGW declined, while terpenic, floral, chemical, pungent and ripe fruit aroma compound series increased. PMID:26593588

  4. Characterization of the key aroma compounds in a commercial Amontillado sherry wine by means of the sensomics approach.

    Science.gov (United States)

    Marcq, Pauline; Schieberle, Peter

    2015-05-20

    An aroma extract dilution analysis (AEDA) carried out on the volatile fraction isolated by extraction/solvent-assisted flavor evaporation (SAFE) distillation from a commercial Amontillado sherry wine revealed 37 odor-active compounds with flavor dilution (FD) factors in the range of 16-4096. Among them, 2-phenylethanol (flowery, honey-like) and ethyl methylpropanoate (fruity) showed the highest FD factors, followed by ethyl (2S,3S)-2-hydroxy-3-methylpentanoate (fruity) reported for the first time in sherry wine. A total of 36 aroma-active compounds located by AEDA were then quantitated by a stable isotope dilution assay, and their odor activity values (OAVs; ratio of concentration to odor threshold) were calculated. The highest OAV was displayed by 1,1-diethoxyethane (2475; fruity), followed by 2- and 3-methylbutanals (574; malty) and methylpropanal (369; malty). Aroma reconstitution experiments and a comparative aroma profile analysis revealed that the entire orthonasal aroma profile of the Amontillado sherry wine could be closely mimicked. PMID:25921555

  5. Characterization of the Key Aroma Compounds in Two Commercial Rums by Means of the Sensomics Approach.

    Science.gov (United States)

    Franitza, Laura; Granvogl, Michael; Schieberle, Peter

    2016-01-27

    Two rums differing in their overall aroma profile and price level (rum A, high price; rum B, low price) were analyzed by means of the Sensomics approach. Application of aroma extract dilution analysis (AEDA) on a distillate of volatiles prepared from rum A revealed 40 aroma-active compounds in the flavor dilution (FD) factor range from 8 to 2048. The identification experiments indicated cis-whiskey lactone, vanillin, decanoic acid, and 2- and 3-methylbutanol with the highest FD factors. The AEDA of a distillate prepared from rum B showed only 26 aroma-active compounds in the same FD factor range. Among them, in particular, ethyl butanoate, 1,1-diethoxyethane, ethyl (S)-2-methylbutanoate, and decanoic acid appeared with the highest FD factors. Thirty-seven compounds having at least an FD factor ≥32 in one of the two rums were quantitated using stable isotope dilution assays or enzyme kits (2 compounds). The calculation of odor activity values (OAVs; ratio of concentration to respective odor threshold) indicated ethanol, vanillin, ethyl (S)-2-methylbutanoate, and (E)-β-damascenone with the highest OAVs in rum A, whereas ethanol, 2,3-butanedione, 3-methylbutanal, and ethyl butanoate revealed the highest OAVs in rum B. Most compounds were present in similar concentrations in both rums, but significant differences were determined for vanillin, cis-whiskey lactone, and 4-allyl-2-methoxyphenol (all higher in rum A) and 3-methylbutanal, 2,3-butanedione, and ethyl butanoate (all higher in rum B). Finally, the aromas of both rums were successfully simulated by a recombinate using reference odorants in the same concentrations as they naturally occurred in the spirits. PMID:26715051

  6. Uptake and Reactions of Formaldehyde, Acetaldehyde, Acetone, Propanal and Ethanol in Sulfuric Acid solutions at 200-240 K: Implications for upper tropospheric aerosol composition

    Science.gov (United States)

    Iraci, L. T.; Williams, M. B.; Axson, J.; Michelsen, R.

    2007-12-01

    The production of light absorbing, organic material in aerosol that is normally considered to be transparent in the UV and visible wavelength regions has significant implications for biogeochemical cycling and climate modelling. Production mechanisms likely involve carbonyl compounds such as formaldehyde, acetone, acetaldehyde and propanal that are present in significant quantities in the upper troposphere (UT). In this study, we have performed experiments focusing on a class of acid catalyzed carbonyl reactions, the formation of acetals. R2C=O + 2R'OH --> R2C(OR')2 + H2O Using a Knudsen cell apparatus, we have measured the rate of uptake of formaldehyde, acetaldehyde, acetone, propanal, and ethanol into sulfuric acid solutions ranging between 40-70 wt% of acid, containing 0-0.1 M of ethanol, acetone or formaldehyde at temperatures of 220-250 K. For all reactant pairs, the aldol condensation path, including self reaction, should be insignificant at the acidities studied. Evidence for reaction between organics was observed for all pairs, except those involving propanal which were likely limited by the very low solubility. We attribute enhanced uptake to the formation of acetals, such as 1,1-diethoxyethane and 2,2- diethoxypropane, among others. Enhanced uptake was observed to proceed on timescales > 1 hour and sometimes shows complex dependence on acidity that is likely related to speciation of the individual carbonyls in acidic solution. The acetal products do not absorb in the visible but are less volatile than parent molecules, allowing for accumulation in sulfuric acid particles, and enhanced uptake. Cross reactions of carbonyls with alcohols in sulfuric acid medium have not been previously measured, yet methanol and ethanol show high solubility and are present at significant concentrations in the UT. Thus even at slow reaction rates, the acetal reaction has ample starting material and proceeds under conditions common to the UT. We will present results for the

  7. 西湖龙井茶香气成分的全二维气相色谱-飞行时间质谱分析%Analysis of Aroma Components in Xihu Longjing Tea by Comprehensive Two-Dimensional Gas Chromatography- Time-of-Flight Mass Spectrometry

    Institute of Scientific and Technical Information of China (English)

    朱荫; 吕海鹏; 林智; 杨停; 施江; 余方林; 戴伟东; 谭俊峰; 郭丽; 张悦; 彭群华

    2015-01-01

    , hentriacontane, acetaldehyde, pentanal, hexanal, furfural, heptanal, phenylacetaldehyde, nonanal, 1-ethoxypropane, 2-ethoxybutane, 1-ethoxybutane, 1,1-diethoxyethane, 1-ethoxypentane, pentanol, tert-butanol, benzyl alcohol, phenethyl alcohol, phytol, diisobutyl phthalate, dibutyl phthalate, ethyl 2-(5-methyl-5-vinyltetrahydrofuran-2-yl) propan-2-yl carbonate, (Z)-hex-3-en-1-yl hexanoate, methyl palmitate, acetoin, 2,4-di-tert-butylphenol, 3-methylbutanoic acid, nonanoic acid, hexadecanoic acid, linoleic acid, octadecanoic acid, dimethyl sulfoxide, benzothiazole, indole, caffeine, linalool oxide (pyranoid), 2,3-dihydrobenzofuran, ethylbenzene, phenylpropane, and 1-methylnaphthalene, were found to be relatively high contents in aroma components of Xihu Longjing tea, suggesting that they played an important role in effecting the aroma quality of Xihu Longjing tea. The analysis of characteristic aroma compositions indicated that enols, aldehydes, alcohols, esters and aromatic hydrocarbons with agreeable smell would be responsible for the outstanding aroma quality of Xihu Longjing tea, and the effects of alkanes, ethers, organic acids and sulphur compounds with no special smell or offensive odor and aroma compounds with low odor threshold values were also worth future research.[Conclusion] The successful application of GC×GC-TOFMS technology in tea aroma analysis has improved the number of identified compounds significantly, which could make up for the defects of GC-MS analysis to some extent and supply the advanced technical support for the future in-depth studies on the chemical composition of tea aroma and formation mechanism of tea aroma quality.%【目的】香气是评价茶叶品质优劣的最重要因子之一,探明茶叶香气的化学组成可进一步丰富茶叶香气化学理论,为改善和提高茶叶香气品质提供重要的科学理论依据。【方法】采用全二维气相色谱-飞行时间质谱联用技术(GC×GC-TOFMS)与气相色谱-质谱联