Fermentation of white wine grapes

White wine grapes must be excluded from air contact as soon as crushed to prevent the grapes from discolouring due to oxidation. Wine oxidation can occur at several stages of winemaking, but as we get closer to bottling, its consequences are more negative, so prevention plays a vital role throughout the production and storage of white wine.
Step 1:  Crush the grapes in a destemmer and add an amount of sodium metabisulphate according to the quantity of grapes in the table here.