What is fining a wine?

Fining is the removal of sediment (proteins and excess tannin among them) that can cloud a finished wine. Several different types of fining agents are available. They all work by attracting the sediment and forming heavy enough “clumps” to settle to the bottom of the fermenter. Fining agents are added prior to bottling, and should always be used prior to filtering. Bentonite is a very fine clay that is mixed with a small amount of water or wine. Isinglass is a liquid made from fish bladders. Gelatin is also used. These are all available from HomeBrew4Less.com