Potassium sorbate

Potassium sorbate[1][2]
IUPAC name	Potassium (2E,4E)-hexa-2,4-dienoate
Other names	E202 Sorbistat-K Sorbistat potassium
Identifiers
CAS number	24634-61-5 Y
PubChem	23676745
SMILES	C\C=C\C=C\C(=O)[O-].[K+]
Properties
Molecular formula	C6H7KO2
Molar mass	150.22 g/mol
Density	1.363 g/cm3
Melting point	270 °C (decomposition)
Solubility in water	58.2% at 20 °C
Solubility	soluble in ethanol, propylene glycol slightly soluble in acetone very slightly soluble in chloroform, corn oil, ether insoluble in benzene
Hazards
LD50	4920 mg/kg (rat, oral)
Y (what is this?)  (verify) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Potassium sorbate is the potassium salt of sorbic acid. Its primary use is as a food preservative (E number 202).^[3] Potassium sorbate is effective in a variety of applications including food, wine, and personal care.

Chemistry

The molecular formula of potassium sorbate is C₆H₇O₂K and its systematic name is potassium (E,E)-hexa-2,4-dienoate. It has a molecular weight of 150.22 g/mol. It is very soluble in water (58.2% at 20 °C). It is prepared by the reaction of sorbic acid with potassium hydroxide.

Uses

Potassium sorbate is used to inhibit molds and yeasts in many foods, such as cheese, wine, yogurt, dried meats, apple cider and baked goods. It can also be found in the ingredients list of many dried fruit products. In addition, herbal dietary supplement products generally contain potassium sorbate, which acts to prevent mold and microbes and to increase shelf life, and is used in quantities at which there are no known adverse health effects^[4]. Labeling of this preservative reads as "potassium sorbate" on the ingredient statement. Also, it is used in many personal care products to inhibit the development of microorganisms for shelf stability. Some manufacturers are using this preservative as a replacement for parabens.

Also known affectionately as "wine stabilizer", potassium sorbate produces sorbic acid when added to wine. It serves two purposes. When active fermentation has ceased and the wine is racked for the final time after clearing, potassium sorbate will render any surviving yeast incapable of multiplying. Yeast living at that moment can continue fermenting any residual sugar into CO₂ and alcohol, but when they die no new yeast will be present to cause future fermentation. When a wine is sweetened before bottling, potassium sorbate is used to prevent refermentation when used in conjunction with potassium metabisulfite. It is primarily used with sweet wines, sparkling wines, and some hard ciders but may be added to table wines which exhibit difficulty in maintaining clarity after fining.

Some molds (notably some Trichoderma and Penicillium strains) and yeasts are able to detoxify sorbates by decarboxylation, producing 1,3-pentadiene. The pentadiene manifests as a typical odor of kerosene or petroleum.^[5]

Toxicology

Potassium sorbate is considered to be safe because of its long term safety record and non-toxic profile. Potassium sorbate is non-irritating and non-sensitizing. Allergic reactions are rare^{[citation needed]} and it is well tolerated when administered internally.^[6]

Potassium sorbate exhibits low toxicity with LD50 (rat) of 4.92 g/kg^[7], similar to table salt^[8]. The amount of potassium sorbate in a serving (100 g) is typically between 0.025% to 0.1% (see sorbic acid), or 25 mg to 100 mg, which is 0.1% to 0.3% the LD50 dose.

Acceptable daily intakes for human is 12.5 mg/kg, or 875 mg daily for a normal adult (70 kg), according to FAO/World Health Organization Expert Committee on Food Additives^[4].

Compendial status

This section requires expansion.

See also

• Sodium benzoate

References

1. ^ Merck Index, 11th Edition, 7661.
2. ^ Potassium sorbate at Sigma-Aldrich
3. ^ Nordic Food Additive Database Nordic Working Group on Food Toxicology and Risk Assessment
4. ^ ^{a b} http://www.inchem.org/documents/jecfa/jecmono/40abcj15.htm
5. ^ The Soft Drinks Companion - A technical handbook for the beverage industry, Chapter 10
6. ^ Potassium sorbate reduces gastric colonization in patients receiving mechanical ventilization. The Division of Pulmonary and Critical Care Medicine, Loyola University, Stritch School of Medicine, Chicago, IL 60611, USA. J Crit Care. 2005 Sep;20(3):281-7. J Crit Care. 2006 Jun;21(2):230. Tulamait, Aiman [corrected to Tulaimat, Aiman]. Abstract
7. ^ http://msds.chem.ox.ac.uk/PO/potassium_sorbate.html
8. ^ http://msds.chem.ox.ac.uk/SO/sodium_chloride.html