Agriculture Reference
In-Depth Information
only for the beginner, but also for the most prestigious of
professional wineries.
Testing Sulfite Levels
It is very rare that you would need to test the sulfite levels in
wine. Simply following the directions in this topic will assure
adequate but not excessive levels of sulfite for most purposes.
However, there are instances where you'll want to know how
much sulfite is in the wine. For example, if you plan to follow
your secondary fermentation with a malolactic fermentation
in order to reduce perceived acidity, most malolactic cultures
will be inhibited by sulfite levels greater than 20 ppm. So if
you have been dosing regularly with sulfite between rackings,
when you rack into a container to initiate malolactic
fermentation, you should test the sulfite levels in your must,
and reduce them if they are too high.
You can purchase sulfite test kits from wine equipment
suppliers. These test kits use what is called the “Ripper”
method and they work quite well with wines that are not
strongly colored. With strongly colored wines, they give a
reading that is too high because the compounds that impart
color to the wine combine with some of the test ingredients
making them inert. You can “guesstimate” the error by
subtracting 10ppm from the results of the test, or you can do a
more elaborate test on your own. I've detailed that test in the
advanced techniques chapter.
To reduce sulfite levels, stir 3% hydrogen peroxide solution
from the pharmacy into your wine and wait an hour. The
amount you need is equal to 1 ml for every ppm reduction per
gallon of wine. So if I have 5 gallons of must with a sulfite
