Plant protein fining
pea protein, potato protein
A vegan substitute for gelatin and isinglass.
Typical dose
Per the product sheet, in the range of the animal finings it replaces.
When to add it
Where gelatin or isinglass would be used, on wine or juice.
Legal limit
No specific limit that this reference states. Additions are still governed by the treating-materials rules where you make wine, so check them.
Vegan
Yes. Nothing animal-derived, so a wine fined with it can still be labelled vegan.
In practice
Pea and potato proteins fine tannin and clarify much as the animal collagens do, with a gentler action, and they let a wine be finished vegan and free of the fish, egg and milk allergens. They are newer, so results vary more by product, and a bench trial matters more, not less.
Others in fining and clarification
Bentonite
Adsorbs unstable protein to prevent haze in whites and roses.
Isinglass
Fish-derived collagen that polishes whites to brilliance at a tiny dose.
Gelatin
Collagen that strips harsh tannin and astringency from reds.
Egg white
The traditional, gentle softener of barrel-aged red tannin.
Casein
Treats browning and light oxidation or taint in whites.
PVPP
A synthetic that removes browning, pinking and bitter phenols.
Kieselsol
A negatively charged fining, paired with gelatin for a compact lees.
Sparkolloid
A polysaccharide clarifier for stubborn hazes that resist other finings.
Activated carbon
A blunt last resort that strips colour and off-odours together.
Diatomaceous earth
A filter aid, rather than a fining, for wines too cloudy to filter.