Tom would highly recommend the use
of PVPP (or Polyclar) on our Riesling from the 2008 harvest. Due to
excessive rain in June-July 2008 and during harvest time, there was botrytis
in some of the Riesling, especially in juices picked up after October
23, 2008. We have also had reports of "pinking" of certain
whites. PVPP would turn your surprise blush back into a
He recommends using a lower
dose if a range is given and working your way up or to do bench
PVPP is used to remove "browning" or "pinking"
pigments. It is used to remove oxidized odors, color and small
amounts of bitter phenolic compounds. Winemakers use it on whites,
blushes and reds. It may strip too much color from reds. It is
most commonly used on white and blush wines. Bench trials are
recommended especially if you need it for a
Mix with 20 times its
weight in cold distilled water.
Allow to set for 3 hours before use; no agitation is necessary during this
time. It should be added to juice or wine during a racking process to
ensure adequate mixing.
PVPP reacts very quickly and
can be removed from the wine (or juice) after 24 hours. However, Polyclar
does not settle out very well. Many winemakers prefer to filter the
wine after a PVPP treatment. Sometimes bentonite or casein is used as an
additional fining material to help PVPP particles to settle.
Filtration is still
recommended for separation.
Polylact is a blend of PVPP and casein in a cellulose base from
Scott Labs. Polylact acts evenly on all types of phenolic compounds and
can be used as both a curative and a preventative against browning and pinking
in white wines and musts.
The rates below are for
Curative Usage rate: 0.3-0.7grams/L
(5 gallons is 19 liters)
Prevent Oxidation: 15-30 grams/hl = 0.15-0.30
grams/L (such as use on a white wine that will be exposed to long or
extreme storage conditions.)
10 from Crosby Baker (BSG)
recommended dose is 1/8 ounce or 3.54 grams per 5 gallons (19 liters) of
wine. It is double that for beer. Overall PVPP is
probably more commonly used by brewers, but winemakers should also be aware of
As with all products, follow
the rate recommended on the label, as products differ. We
currently have both the Polyclar 10 from Crosby and Baker and Polylact from
Good Luck and may your wines