Chemistry:Isopropyl methoxy pyrazine
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Preferred IUPAC name
2-Methoxy-3-(propan-2-yl)pyrazine | |
Other names
2-Isopropyl-3-methoxypyrazine
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Properties | |
C8H12N2O | |
Molar mass | 152.19 g/mol |
Hazards | |
GHS pictograms | |
GHS Signal word | warning |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). | |
verify (what is ?) | |
Infobox references | |
Isopropyl methoxy pyrazine (IPMP) is a methoxypyrazine, a class of chemical compounds that produce odors. The odor is rather undesirable and is produced by the Asian lady beetle or by the actinomycete Streptomyces sp.[2] It can be detected by human taste at concentrations of as low as 2 nanograms per litre.[3]
Presence in wine grapes
The odor of IPMP tends to be undesirable in the case of certain wines.[4]
Cabernet Sauvignon has high levels of methoxypyrazines.[5][6] Two methoxypyrazine compounds, 3-isobutyl-2-methoxypyrazine (IBMP) and 3-isopropyl-2-methoxypyrazine, are considered to be important determinants of green flavours in Sauvignon blanc wines.[7]
Presence in coffee
IPMP is also an important flavour compound in coffee and is responsible for causing an off-taste called "potato taste" in East African coffee.[8] The insects Antestiopsis are also implicated in causing the taste.[9]
See also
References
- ↑ GHS: sigma-aldrich 243132
- ↑ Three highly odorous metabolites from an actinomycete: 2-Isopropyl-3-methoxy-pyrazine, methylisoborneol, and geosmin. Nancy N. Gerber, Journal of Chemical Ecology, Volume 3, Number 4, pp. 475-482, doi:10.1007/BF00988190
- ↑ Cristina Sala; Olga Busto; Josep Guasch; Fernando Zamora. Factors affecting the presence of 3-alkyl-2- methoxypyrazines in grapes and wines. A review. (Report). http://www.tesisenred.net/bitstream/handle/10803/8653/15-PaperC2.pdf. Retrieved 2012-04-01.
- ↑ Trace flavour components of grapes
- ↑ winepros.com.au Oxford Companion to Wine methoxypyrazines
- ↑ Oz Clarke Encyclopedia of Grapes pg 223 Harcourt Books 2001 ISBN:0-15-100714-4
- ↑ Marais, J., Hunter, J.J., & Haasbroek, P.D. (1999). Effect of microclimate, season and region on Sauvignon blanc grape composition and wine quality. South African Journal of Enology and Viticulture, 20, 19-30.
- ↑ Czerny, M.; Grosch, W. (2000). "Potent Odorants of Raw Arabica Coffee. Their Changes during Roasting". Journal of Agricultural and Food Chemistry 48 (3): 868–872. doi:10.1021/jf990609n. PMID 10725165.
- ↑ B. Bouyjou; B. Decazy; G. Fourny. "L’élimination du " goût de pomme de terre " dans le café Arabica du Burundi" (in fr). Plantations, Recherche, Développement 6 (2): 107–115. http://publications.cirad.fr/une_notice.php?dk=392315.