Preservatives in wine
The use of Sulphur in wine dates back to Roman times when Sulphur was burnt in storage vessels before filling to prevent spoilage of wine. More recently Sulphur Dioxide was introduced directly into wine to take advantage of its remarkable properties.
Why use Sulphur?
The main use of Sulphur Dioxide is for its anti-oxidant and anti-microbial qualities. This means that it will inhibit the growth of unwanted yeast and bacteria as well as binding to oxygen. Excess oxygen causes wine to spoil. In addition to these properties Sulphur is considered low irritant and easy to detect if present in high quantities. Despite the benefits, there are some people who allergic to the sulphur.
What regulations apply?
Sulphur is an authorised additive for use as an anti-oxidant in wine (including organic wines) as long as the total addition does not exceed 250mg/L and 400mg/L for certain sweet wines. This limit is set by Foodstandards Australia and New Zealand. Even if Sulphur Dioxide is not added to wine there will always be a small amount of Sulphur Dioxide present as it is a by-product of alcoholic fermentation.
The addition of liquid Sulphur Dioxide directly into a wine appears as preservative 220 on a wine label. Addition as Salts of Sulphur that are dissolved in water and when added to the wine appear on wine labels as preservative 221, 222, 223, 224, 225 or 228.