Sulfite in wine

The practice of adding sulfite to wine to preserve it from the decay of oxidation as the wine ages has been practice for at least 3000, years. The term 'sulfites' is an inclusive term for sulfur dioxide (SO2).

Sulfur dioxide is a preservative and it is widely used in because of its antioxidant and antibacterial properties. Sulfur dioxide plays a very important role in preventing oxidization and maintaining a wine's freshness.

Sulfite is added to the wine industry using o

ne of 3 simple methods:
*Sulfite powder (dissolved in water)
*Campden tablets (crushed and dissolved in water)
*3-10% dilute sulfite solution

In general, wines contain on average of about 80 ppm of sulfites. At levels approaching the maximum, the sulfur in the wine becomes noticeable and unpalatable.

The levels of sulfite in a wine decline gradually over the aging of the wine due to its oxygen scavenging. The rate of decline depends on the acidity and the type of wine and the amount in the wine before bottling.

In the United States, the maximum permissible concentration of sulfites is 350 ppm, and any wine domestic or imported with more than 10 ppm – must display the sulfites warning.
Sulfite in wine

Sulfur dioxide as food additive

Sulfur dioxide has been used since olden times in the form of 1-2% aqueous solutions as a disinfectant for equipment, barrels, bottles, corks and other ancillary items for the wine, drinks and food industries.

Fumes of burning sulfur were used as a sanitizing agent in wine-making by the ancient Egyptians and Romans. The practice is continued by the modern wine industry.

The compound is a colorless, nonflammable gas or liquid under pressure, with a suffocating, pungent odor.

Sulfur dioxide is used to prevent browning in certain dried fruits and to prevent wild yeast growth in wines used to make vinegar.

Sulfur dioxide also is used to control the growth of undesirable microorganism in soft fruits, fruit juices, wines, sausages, fresh shrimp, and acid pickles and using extraction of starches.

It is added to expressed grape juices used for making wines to inhibit molds, bacteria, and undesirable yeasts.

The most obvious drawback of sulfur dioxide is its intense pungent odor, which may be apparent in foods it is used to treat.
Sulfur dioxide as food additive