Occurs in essential oils, e.g. lavender, hop. Also present in apple, banana, blackberry, hog plum, wheat bread, malt whiskey, red or white wine, tea, toasted oat flakes and other foodstuffs. Flavouring agent Butanal is an organic compound that is the aldehyde analog of butane. It is a colorless flammable liquid with an acrid smell. It is miscible with most organic solvents.(wikipedia); IN man, butanal is a biomarker for oxidative damage to lipids, proteins and DNA. (PubMed ID 15763951 ); Butyraldehyde, also known as butanal, is an organic compound with the formula CH3(CH2)2CHO. This compound is the aldehyde derivative of butane. It is a colourless flammable liquid with an acrid smell. It is miscible with most organic solvents.