Let’s talk about the term buttery. Buttery is a term that you most often see associated with Chardonnay. Wine goes through fermentation. Fermentation is pretty straightforward chemistry. You have yeast and they eat the sugars that are found in those fresh grapes. The yeast converts that sugar into alcohol.
There is a second fermentation that happens and it is called malolactic fermentation. Typically all red wines go through malolactic fermentation. Some whites do and some don’t. Chardonnay is one white wine that typically does go through malolactic fermentation and that is for a really specific reason.
Grapes naturally have a type of acidity found in them called malic acid. Malic acid is sort of like if you bite into a fresh Granny Smith Apple, or maybe one that is not quite ripe, you get that kind of bracing almost a stringent acidity. Well, what happens with malolactic fermentation is a very specific bacteria is introduced to convert that malic acid into a softer lactic acid. Lactic acid is the kind of acid you find in a lot of dairy products like yogurt or sour cream. It makes the wine softer, rounder, and creamier.
At the same time, one of the byproducts of that malolactic fermentation is a chemical called diacetyl. That’s the same chemical that they use in creating that fake movie popcorn butter aroma. So, there you end up with a buttery wine.
Learn Wine featuring Master Sommelier Emily Wines