The chemical compound (2-methoxy-3,5-dimethylpyrazine, abbreviation MDMP) was isolated by the AWRI (Australian Wine Research Institute) in 2004. It is found in cork stoppers and negatively affects the flavour of wines. These smell of fresh cork, wood or dust, which is considered a wine defect from the perception threshold or quantity of 2 to 4 ng/litre. In Australia it is called "fungal must" (mushroom odour). The substance is probably the second most common cause of cork taint in Australian wines after trichloroanisole (TCA). See also under Methoxypyrazine.
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