60ºF/16ºC for red wines, around 32ºF/0ºC for
whites — reduce the solubility of all the
dissolved solids, and cause the wine to cloud
up with a fine precipitate of various
complexes of proteins, carbohydrates, and
tannins. Late in the racking procedure, the
wine may be fined: that is, a substance will be
added to the wine that attracts these
suspended particles to itself, and then settles
to the bottom, carrying them with it. Gelatin,
egg white, bentonite clay, and synthetic
materials are used. Any particles remaining in
the wine after racking and fining can be
removed by passing it through a centrifuge or
filter. Winemakers may choose to limit or
omit the fining and filtration steps, since they
remove some flavor and body along with the
undesirable particles.
Brettanomyces, the Controversial Barrel
Yeast
Some wines, including classic reds from