Tag Archives: sulfur dioxide

What Are Sulfites ?

What are sulfites or sulphites ?

Sulfites are a group of preservatives containing the sulfite ion SO3 ²‾. These food additives are used in many ways, in many different food and non-food products. Different items contains different forms of sulfites or sulfur dioxide and I am listing them all separately with their corresponding E-numbers. I will be adding new things on these lists when I find out about those.

Sulfites in wines and in certain beers reduces bacterial growth as wine/beer ferments. Wines and beers will always contain some natural sulfites as sulfites are also a natural by product of fermentation.

Sulfites inhibit oxidation of fruits and vegetables, but sulfites are banned in fresh products in many countries, but they are allowed in dried fruits, in fruit jams, in peeled, pre -prepared potatoes etc.

Sulfites are added in certain seafood, like shrimps and lobster to prevent black spots, melanosis. But sulfites are also often added into the ice where all seafood and fish are kept.

Sulfites are powerful bleaching agent and those are used to bleach food starches like tapioca, potato, corn etc. As well as beet- and cane sugar. Unusually white colour in any food product could mean that it is bleached with sulfites.

Sulfites are also used as a dough condition, and are mixed with various flours, specially premixed flours for cakes, muffins etc.

Sulfites in medicines are used to maintain the stability and potency of the active ingredients.

You can find sulfites also in artificial snow or traces of sulfites might be found in swimming pools.

Sulfites can be everywhere so you really need to memorize the following list of E-numbers for sulfite containing food additives. In Europe E-numbers for all additives are used widely, but you might also see the written words of sulfites and/or sulfur dioxide in labels. In other countries E-numbers are not often used, but a label stating contain sulfites must be clearly written when the product contains more than 10 ppm (parts per million) of sulfites. Always read the labels, being it food, medicine or cosmetic product before using it.

E150b Caustic sulfite caramel

E150d Sulfite ammonia caramel

E220 Sulfur dioxide, SO2 at standard atmosphere is a toxic gas.

  • Occurs naturally by volcanic activity, but is also produced industrially by combustion of elemental sulfur.
  • One of the oldest food additives. Read more here.

E221 Sodium sulfite

E222 Sodium bisulfite (sodium hydrogen sulfite)

E223 Sodium metabisulfte

E224 Potassium metabisulfite

E225 Potassium sulfite

E226 Calcium sulfite

E227 Calcium hydrogen sulfite

E228 Potassium hydrogen sulfite