Malolactic fermentation (malo, MLF or malolactic conversion) is a bacterial process, typically controlled by the winemaker, that converts malic acids (the green apple kind of acids) into the softer lactic acids (the dairy kind – think the kind of acidity you see in yoghurt). Most red wines go through this process whereas whites it is a winemaking decision, as it does affect the flavour of the wine. It is also not an all-or-nothing decision – a winemaker may choose to stop malolactic fermentation part-way through or to blend wine that has gone through malo with wines that haven’t. If you’re picking up dairy notes in a white wine – such as butter, cream or yoghurt – there’s a good chance that it has gone through some degree of malolactic fermentation.
