Pressing is the process of applying pressure to grapes or fermented grape solids to separate liquid from skins, seeds and other solids. In white-wine production, grapes are commonly pressed before fermentation so the juice can be clarified and fermented separately. In red-wine production, pressing usually takes place after maceration or fermentation to separate the new wine from the skins and seeds.
White grapes are generally pressed soon after harvest, although some producers use a period of skin contact before pressing. Gentle pressing helps extract juice while limiting the extraction of harsh phenolics from skins and seeds. The juice may then be settled or clarified before fermentation.
Red grapes are commonly fermented with their skins to extract colour, tannin and flavour. Once the desired maceration is complete, free-run wine is drained from the tank and the remaining solids are pressed. Pressing pressure and duration affect the amount and character of press wine, so wineries may separate different press fractions.
Example: white grapes may be gently pressed before fermentation, while a red Cabernet Sauvignon may be pressed after fermentation to separate the wine from its skins.
Crushing breaks grape skins to release juice. Pressing applies pressure to separate liquid from the solids. The processes are related but are not the same operation.
Chef’s note: pressing pressure influences the composition of the juice or wine. Gentle pressing and careful separation of fractions help the winemaker control bitterness, tannin and texture.
This term is one of hundreds covered in depth across OCS courses, learning paths, and 1-on-1 coaching with Chef Eric.
