Methoxypyrazines are a class of chemical compounds that produce odors. The odors tend to be undesirable, as in the case of certain wines, or as in the case of the Asian Lady Beetle

Asian lady beetle

Harmonia axyridis is a large coccinellid beetle. Its colour ranges from yellow-orange to black, and the number of spots between 0 and 22. It is native to eastern Asia, but has been introduced to North America and Europe to control aphids and scale insects...

 which produces isopropyl methoxy pyrazine

Isopropyl methoxy pyrazine

Isopropyl methoxy pyrazine 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....

 (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

Cabernet Sauvignon

Cabernet Sauvignon is one of the world's most widely recognized red wine grape varieties. It is grown in nearly every major wine producing country among a diverse spectrum of climates from Canada's Okanagan Valley to Lebanon's Beqaa Valley...

 have high levels of methoxypyrazines. Two methoxypyrazine compounds, 3-isobutyl-2-methoxypyrazine (IBMP) and 3-isopropyl-2-methoxypyrazine (IPMP), are considered to be important determinants of green flavours in Sauvignon blanc

Sauvignon blanc

Sauvignon Blanc is a green-skinned grape variety which originates from the Bordeaux region of France. The grape most likely gets its name from the French word sauvage and blanc due to its early origins as an indigenous grape in South West France., a possible descendant of savagnin...

wines.