Abstract A characteristic component of butter flavour is 2, 3-dimethyl-2, 4-nonadien-4-olide, the enol lactone of 2, 3-dimethyl-4-oxo-2-nonenoic acid. Homologues have not been found. The substance which has a strong odour reminiscent of celery and occurs in an amount of about 0.5 mg/kg butter, was called “bovolide”.
