My fining posts seem to be quite popular judging by this sites web stats, so why not a few more.

It’s pretty hard to top “fish products” as a strange fining agent or allergen declaration but “milk products” is still rather odd.

Like isinglass and egg whites, casein (a milk product) is a protein fining aimed at removing bitterness, off flavors and softening the palate of white wines and sherry style wines. It can also lighten the color. The active ingredient is protien casein and although milk can be used, winemakers normally use specially prepared casein fining agents like sodium caseinate.

The problem with casein fining is that it doesn’t want to stay in the acid environment of wine and is difficult to dissolve. The bonus of that though is that the reaction is quick and the settling out process fast.

Again the thing remember is that this is a processing aid, not something that is intended to stay in the wine. There is a possibility that minute traces may remain but they are almost impossible to detect with current equipment. For example additions are at the rate of (roughly) 50 –300 grams per 1000 Litres to begin with. The concept of the fining agent is that it precipitates out of the wine along with the components you are trying to remove. Fining agents are not something that will enhace a wine by there presence, but by there absence.