Isopropyl methoxypyrazine (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]
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]
^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
^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. PMID10725165.