Vegan wines are made without animal products, so winemakers either leave the particles left behind in the wine-making process to sink naturally to the bottom of the wine, or use non-animal fining products, usually bentonite, a form of clay or pea protein, to bind to those particles and make them big enough to filter out, thus clarifying the wine.

This process if called 'fining' and is traditionally done using isinglass which is derived from the dried swim bladder of fish, but egg whites or gelatine can also be used - but definitely not in a vegan wine!