Potassium sorbate

Potassium sorbate[1][2]
Names
IUPAC name
Potassium (2E,4E)-hexa-2,4-dienoate
Other names
E202
Sorbistat-K
Sorbistat potassium
Identifiers
24634-61-5 Yes
ChEBI CHEBI:77868 
ChemSpider 4445644 Yes
Jmol-3D images Image
KEGG D02411 Yes
PubChem 23676745
Properties
Molecular formula
C6H7KO2
Molar mass 150.22 g·mol−1
Appearance White crystals
Odor yes
Density 1.363 g/cm3
Melting point 270 °C (518 °F; 543 K) (decomposes)
58.5 g/100 mL (100 °C)
Solubility in other solvents Soluble in ethanol, propylene glycol
Slightly soluble in acetone
Very slightly soluble in chloroform, corn oil, ether
Insoluble in benzene
Hazards
NFPA 704
Flammability code 1: Must be pre-heated before ignition can occur. Flash point over 93 °C (200 °F). E.g., canola oil Health code 2: Intense or continued but not chronic exposure could cause temporary incapacitation or possible residual injury. E.g., chloroform Reactivity code 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g., liquid nitrogen Special hazards (white): no codeNFPA 704 four-colored diamond
1
2
0
4340 mg/kg (oral, rat)[3]
Except where noted otherwise, data is given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
  verify (what is: Yes/?)
Infobox references

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).[4] 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.

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.[5][6][7]

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.[8] It is used in the preparation of items such as Sweet maple syrup and milkshakes served by fast food conglomerates such as Mc Donalds. [9] [10] [11] 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 there are no known adverse health effects, over short periods of time.[12] 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.[13]

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 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 piperylene (1,3-pentadiene). The pentadiene manifests as a typical odor of kerosene or petroleum.[14]

Toxicology

Potassium sorbate is a skin, eye and respiratory irritant.[15] Although some research implies it has a long-term safety record,[16] 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, and hence found that it negatively affects immunity.[17] 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.[18] Regardless, it has not been found to have any carcinogenic effects in rats.[19][20][21]

Typical usage rates of potassium sorbate are 0.025% to 0.1% (see sorbic acid), which in a 100 g serving yields intake of 25 mg to 100 mg. Acceptable daily intake for human consumption is 12.5 mg/kg, or 875 mg daily for an average adult (70 kg), according to FAO/World Health Organization Expert Committee on Food Additives.[12]

See also

References

  1. Merck Index, 11th Edition, 7661.
  2. Potassium sorbate at Sigma-Aldrich
  3. http://chem.sis.nlm.nih.gov/chemidplus/rn/590-00-1
  4. Nordic Food Additive Database Nordic Working Group on Food Toxicology and Risk Assessment
  5. Erich Lück, Martin Jager and Nico Raczek "Sorbic Acid" in Ullmann's Encyclopedia of Industrial Chemistry, 2011, Wiley-VCH, Weinheim. doi:10.1002/14356007.a24_507.pub2
  6. patent process for commercial potassium sorbate
  7. CFNP TAP Review
  8. Erich Lück, Martin Jager and Nico Raczek "Sorbic Acid" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2000.doi:10.1002/14356007.a24_507
  9. "Ingredients - Vanilla Mc Shake". Mc Donalds USA. Retrieved 24 April 2014.
  10. "Nutrition Information". Mc Donalds UK. Retrieved 24 April 2014.
  11. "15 Horrifying Reasons to Never Let Anyone You Love Near a McDonald's". Bin'scorner. Retrieved 24 April 2014.
  12. 12.0 12.1 "036. Sorbate, potassium (FAO Nutrition Meetings Report Series 40abc)". Inchem.org. Retrieved 2013-02-22.
  13. Tulamait, Aiman; Laghi, F; Mikrut, K; Carey, RB; Budinger, GR (2005). "Potassium sorbate reduces gastric colonization in patients receiving mechanical ventilization". J Crit Care 20 (3): 281–287. doi:10.1016/j.jcrc.2005.03.002. PMID 16253799.
  14. The Soft Drinks Companion - A technical handbook for the beverage industry, Chapter 10
  15. "Potassium Sorbate". Retrieved 2013-02-22.
  16. Tulamait, Aiman; Laghi, F; Mikrut, K; Carey, RB; Budinger, GR (2005). "Potassium sorbate reduces gastric colonization in patients receiving mechanical ventilization". J Crit Care 20 (3): 281–287. doi:10.1016/j.jcrc.2005.03.002. PMID 16253799.
  17. Mamur, Sevcan; Yüzbaşıoğlu, Deniz; Ünal, Fatma; Yılmaz, Serkan (2010). "Does potassium sorbate induce genotoxic or mutagenic effects in lymphocytes?". Toxicology in Vitro 24 (3): 790–4. doi:10.1016/j.tiv.2009.12.021. PMID 20036729.
  18. Kitano, K; Fukukawa, T; Ohtsuji, Y; Masuda, T; Yamaguchi, H (2002). "Mutagenicity and DNA-damaging activity caused by decomposed products of potassium sorbate reacting with ascorbic acid in the presence of Fe salt". Food and Chemical Toxicology 40 (11): 1589–94. doi:10.1016/S0278-6915(02)00119-9. PMID 12176085.
  19. Hendy, R J; Hardy, J; Gaunt, I F; Kiss, I S; Butterworth, K R (1976). "Long-term toxicity studies of sorbic acid in mice". Food and Cosmetics Toxicology 14 (5): 381–86. doi:10.1016/S0015-6264(76)80173-3. PMID 1010505.
  20. Gaunt, I F; Butterworth, K R; Hardy, J; Gangolli, S D (1975). "Long-term toxicity of sorbic acid in the rat". Food and Cosmetics Toxicology 13 (1): 31–45. doi:10.1016/0015-6264(75)90080-2. PMID 1123201.
  21. Mason, P L; Gaunt, I F; Hardy, J; Kiss, I S; Butterworth, K R; Gangolli, S D (1976). "Long-term toxicity of parasorbic acid in rats". Food and Cosmetics Toxicology 14 (5): 387–94. doi:10.1016/S0015-6264(76)80174-5. PMID 1010506.