Vegan and vegetarian wine

This is one of the most searched practical questions about wine and one of the least well answered, largely because the honest answer involves explaining what fining is.

A great deal of wine is already vegan without saying so, which is why the absence of a mark tells you very little.

Fining adds a substance that binds unwanted material — excess tannin, protein that would later form haze, unstable colour — so that it can be settled or filtered out.

Egg white is traditional for softening tannin in red wine; casein for treating browning in whites; gelatin as a general tannin fining; isinglass, from fish swim bladders, for clarifying white wine.

Bentonite, a clay, is the standard protein fining for white wine and is not animal-derived. Pea and potato protein preparations are now widely used as alternatives.

A good deal of wine is not fined at all, particularly reds that have had long enough in barrel to clarify by settling.

Because these are processing aids removed before bottling, they generally need not be declared. Egg and milk derivatives are the exception where residues may remain: EU and UK allergen rules require declaration above a threshold, which is why some labels carry "contains egg" or "contains milk".

It is a genuine consumer question with a genuine answer, and the answer is that the certification mark is the reliable signal — not the ingredients, and not the absence of a warning.