Diacetyl is a buttery-tasting compound that is a by-product of malolactic fermentation, the process in which beneficial bacteria turn sharp-tasting malic acid in wine to softer lactic acid. Chardonnays that have gone through malolactic fermentation often have noticeable diacetyl. Butteriness in chardonnay does not come from oak; although many wine drinkers assume this is the case.

Get WineSpeed

Join tens of thousands of other wine lovers. Get each week’s edition of WineSpeed delivered to your inbox every Friday. It’s fast. It’s free. It’s the smartest way to stay up to speed on wine.
Email address
First Name
Last Name
Other Way You Heard About Us
Be sure to check your inbox to confim your subscription.