Methoxypyrazines are a class of chemical compounds that produce odors. The odors tend to be undesirable, as in the case of certain wines,Trace flavour components of grapes or as defensive chemicals used by insects such as Harmonia axyridis which produces isopropyl methoxy pyrazine (IPMP). They have also been identified as additives in cigarette manufacture. Detection thresholds are very low, typically near 2 parts per trillion (1 ng/L).
Examples of methoxypyrazines in wine grapes Cabernet Sauvignon has high levels of methoxypyrazines.winepros.com.au Oxford Companion to Wine methoxypyrazines Oz Clarke Encyclopedia of Grapes pg 223 Harcourt Books 2001 Two methoxypyrazine compounds, 3-isobutyl-2-methoxypyrazine (IBMP) and 3-isopropyl-2-methoxypyrazine (IPMP), are considered to be important determinants of "green" (i.e., herbal, grassy, or vegetal) flavours in Sauvignon blanc wines.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.
See also Alkylpyrazines
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