Sorbic acid

Hardly soluble in water, sorbic acid is used by winemakers in its salified form: potassium sorbate, E202. This soluble salt is first diluted in water, then added to the must or wine before bottling. This white crystalline powder then dissociates into potassium ions and sorbic acid, not to be confused with ascorbic acid ! Sorbic acid is considered to have three major oenological applications.

It prevents wine refermentation problems

Sorbic acid's antifungal properties make it a popular yeast inhibitor for preventing the resumption of alcoholic fermentation. This ensures the stabilization of wines with residual sugars, such as semi-dry, sweet or syrupy wines.

It protects wine from certain fungal diseases

Sorbic acid's antifungal activity also prevents development of undesirable yeasts such as Candida, Pichia or Hansenula. These microscopic fungi can be responsible for blossom blight, which, despite its pretty name, gives wine a vent-like odor.

It offers an alternative to sulfiting wines

Some winemakers use potassium sorbate to limit the addition of sulfur dioxide (sulfites) to their wines. However, this preservative must always be used in the presence of SO2: this prevents it from being attacked by lactic acid bacteria, against which it has no effect, giving rise to an odor reminiscent of geranium. A minimum level of 20 to 40 mg/l of free SO2 is therefore required. If this level is not reached, or if the wine is not treated, potassium sorbate must be added in combination with sulfur dioxide.

Regulation of the use of potassium sorbate in wine

Authorized as a winemaking adjuvant since 1960, the addition of sorbic acid must comply with amaximum regulatory dose: 200 mg/l,soit 275 mg/l de sorbate de potassium. Its use is forbidden in organic farming, and therefore in organic, natural and biodynamic wines without additives.

A brief history of sorbic acid

Naturally present in the berries of the rowan, an exotic tree with small red berries, this acid was discovered in 1859 by a German chemist, August Wilhelm von Hofmann. It wasn't until 1930 that its antifungal and antimicrobial activity was described, leading to its commercialization some twenty years later. Today, sorbic acid is one of the world's most widely used food preservatives..

A food preservative as well as a pharmaceutical and cosmetic one

Commercialized in its synthetic form from ketene and crotonaldehyde, sorbic acid is colorless, odorless and tasteless.. These characteristics, combined with its antifungal action, mean that it is used in many medicines, creams, lotions and industrial food preparations (pastries, confectionery, sauces, etc.).

The use of sorbic acid is authorized and regulated by the European Food Safety Authority (EFSA), hence the allocation of an E number. Its consumption is thus recognized as safe within the limit of an acceptable daily intake of 25 mg/kg/d. The rare reactions or side effects reported consist of skin irritation on direct contact in the most sensitive individuals.