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. The grapes that we work with are grown without using synthetic pesticides, herbicides, fungicides, or fertilizers. - Broc Cellars