How Is SO2 Prepared Commercially What Are The Conditions For It?

A commercial sulfur dioxide cork sterilization treatment was assessed microbiologically. The treatment
inactivated, respectively, 80% and almost 100% of the
bacterial and mold colony forming units present on the
corks. Penicillium spp., predominant among the untreated cork microflora, were almost completely inactivated by the treatment. Bacillus spp. Were found at
much lower levels than molds on the corks, but appeared
less susceptible to the treatment than Penicillium spp.
Yeasts were rarely detected on the corks.
Example:
A faint purple color was produced when 2.2 milliliters of 0.01
N iodine solution was added to 10 milliliters of white wine. The
free SO2 level of this wine was obtained by multiplying 3200
times 2.2 (the quantity of iodine solution) times 0.01 (the
normality of the iodine solution). The multiplication (3200 X 2.2
X .01) gives 70.4 milligrams per liter of free sulfur dioxide.
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