Formula C6H7KO2 Melting point 270 °C Soluble in Water | Molar mass 150.22 g/mol Density 1.36 g/cm³ Appearance White crystals | |
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IUPAC ID Potassium (2E,4E)-hexa-2,4-dienoate | ||
Potassium sorbate
Potassium sorbate is the potassium salt of sorbic acid, chemical formula CH3CH=CH−CH=CH−CO2K. It is a white salt that is very soluble in water (58.2% at 20 °C). It is primarily used as a food preservative (E number 202). Potassium sorbate is effective in a variety of applications including food, wine, and personal-care products. While sorbic acid is naturally occurring in some berries, virtually all of the world's production of sorbic acid, from which potassium sorbate is derived, is manufactured synthetically.
Contents
Is potassium sorbate bad for you
Production
Potassium sorbate is produced industrially by neutralizing sorbic acid with potassium hydroxide. The precursor sorbic acid is produced in a two-step process via the condensation of crotonaldehyde and ketene.
Uses
Potassium sorbate is used to inhibit molds and yeasts in many foods, such as cheese, wine, yogurt, dried meats, apple cider, soft drinks and fruit drinks, and baked goods. Its breakdown to sorbitol, a sugar alcohol, has been shown to increase the chances of a bowel movement from eating prunes. It is used in the preparation of items such as maple syrup and milkshakes served by fast-food restaurants such as McDonald's. 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. It is used in quantities at which no adverse health effects are known, over short periods of time. Labeling of this preservative on ingredient statements reads as "potassium sorbate" or "E202". 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. Tube feeding of potassium sorbate reduces gastric burden of pathogenic bacteria.
Also known 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 renders 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 piperylene (1,3-pentadiene). The pentadiene manifests as a typical odor of kerosene or petroleum.
Toxicology
Pure potassium sorbate is a skin, eye and respiratory irritant.
Typical culinary usage rates of potassium sorbate are 0.025% to 0.1% (see sorbic acid), which in a 100 g serving yields an intake of 25 mg to 100 mg. The maximal acceptable daily intake for human consumption is 25 mg/kg, or 1750 mg daily for an average adult (70 kg). Under some conditions, particularly at high concentrations or when combined with nitrites, potassium sorbate has shown genotoxic activity in vitro.
Although some research implies that potassium sorbate has a long-term safety record, in vitro studies have shown that it is both genotoxic and mutagenic to human blood cells. Potassium sorbate is found to be toxic to human DNA in peripheral blood lymphocytes, hence it negatively affects immunity. It is often used with ascorbic acid and iron salts, as they increase its effectiveness, but this tends to form mutagenic compounds that damage DNA molecules. Regardless, three studies have not found it to have any carcinogenic effects in rats.