Wineries may use animal derived products in the "Fining Process".
Examples of animal
products used are:
Bulls blood is also used in some Mediterranean countries but is not allowed
in the US or France.
To remove proteins, yeasts, and
other organic particles which are in suspension during the making of the
wine, a "fining
agent" is added to the top of the vat. As it sinks down, the particles
adhere to the agent, and are carried out of suspension. None of the fining agent
remains in the finished product sold in the bottle, and not all wines are fined.
As an alternative to the animal
products Bentonite, a natural, inert clay powder, can be used to clarify the
wine. There are even some very patient vintners who let the wine's sediments
settle naturally. Winemakers are not required to put on their label which
clarifier is used, since it is removed from the final product.