| Title: | Quantifying the contribution of grape hexoses to wine volatiles by high-precision [U(1)(3)C]-glucose tracer studies |
| Author(s): | Nisbet MA; Tobias HJ; Brenna JT; Sacks GL; Mansfield AK; |
| Address: | "Department of Food Science, Cornell University - NYSAES , Geneva, New York 14456, United States" |
| ISSN/ISBN: | 1520-5118 (Electronic) 0021-8561 (Print) 0021-8561 (Linking) |
| Abstract: | "Many fermentation volatiles important to wine aroma potentially arise from yeast metabolism of hexose sugars, but assessing the relative importance of these pathways is challenging due to high endogenous hexose substrate concentrations. To overcome this problem, gas chromatography combustion isotope ratio mass spectrometry (GC-C-IRMS) was used to measure high-precision (13)C/(12)C isotope ratios of volatiles in wines produced from juices spiked with tracer levels (0.01-1 APE) of uniformly labeled [U-(13)C]-glucose. The contribution of hexose to individual volatiles was determined from the degree of (13)C enrichment. As expected, straight-chain fatty acids and their corresponding ethyl esters were derived almost exclusively from hexoses. Most fusel alcohols and their acetate esters were also majority hexose-derived, indicating the importance of anabolic pathways for their formation. Only two compounds were not derived primarily from hexoses (hexanol and isobutyric acid). This approach can be extended to other food systems or substrates for studying precursor-product relationships" |
| Keywords: | Carbon Isotopes Fermentation Fruit/*chemistry Gas Chromatography-Mass Spectrometry/methods Hexoses/*analysis Vitis/*chemistry Volatile Organic Compounds/*analysis Wine/*analysis; |
| Notes: | "MedlineNisbet, Mark A Tobias, Herbert J Brenna, J Thomas Sacks, Gavin L Mansfield, Anna Katharine eng R01 GM103437/GM/NIGMS NIH HHS/ RR031264/RR/NCRR NIH HHS/ Research Support, N.I.H., Extramural Research Support, U.S. Gov't, Non-P.H.S. 2014/06/25 J Agric Food Chem. 2014 Jul 16; 62(28):6820-7. doi: 10.1021/jf500947x. Epub 2014 Jul 1" |
