IF you use ascorbic acid in wine, please note that it
reacts with the SO2. Test the SO2 level and adjust as needed, otherwise the
wine will oxidize. Even though Ascorbic acid is an anti-oxidant in wines with
SO2, it can cause oxidation!
Acid is an anti-oxidant used as a
partial substitute for sulfur dioxide, or used to prevent oxidation, which creates a dull and unpleasant flavor and
to prevent discoloring in the final product.
Ascorbic Acid, like Copper
Sulfate, is often used to treat hydrogen sulfide (H2S) or ‘mercaptans’, which presents as a rotten egg scent in
your wine. If you have advanced H2S ‘disulfide’, the scent could be described as burnt rubber or garlic-like and
the wine will not improve with the treatment of Copper Sulfate alone.
The use of 0.25gm Ascorbic Acid
per gallon will often help by converting the disulfides back to mercaptans. The process may take up to three weeks,
after which the wine should be treated with Copper Sulfate.
Do a bench test first to determine
the need and or the dose for ascorbic acid. http://www.bcawa.ca/winemaking/h2s.htm MORE, read this page!
This article explains the connection of ascorbic acid use with this treatment, as some instructions will
indicate to add it after treatment and some before!
Some sources recommend always
adding the ascorbic acid first! SO do Bench test
first to determine the need for ascorbic acid and the
Other sources recommend treating first with Copper Sulfate but if the problem persists, then treatment with
Ascorbic Acid will be necessary.
Use 0.25 grams of ascorbic acid
per gallon. You can use your grain scale to
determine different rates for your bench test.
So, saying it again as there is
always more than meets the eye:
IF you use ascorbic acid in wine, it reacts with the SO2. Test the SO2 level and
adjust as needed, otherwise the wine will oxidize. Even though Ascorbic acid is
an anti-oxidant in wines with SO2, it can cause oxidation!