At Broc Cellars, all of our wines are made using spontaneous fermentation, a process that means we only use native yeasts and bacteria that exist on the grapes in order to make wine. We don’t add anything – this includes nutrients, yeast, bacteria, enzymes, tannins or other popular fermentation agents. Sulphur is a naturally occurring element in all wine, the amount found can vary. We add little to no S02, depending on the wine and style.