Potassium metabisulfite, K2S2O5, also known as potassium pyrosulfite, is a white crystalline powder with a pungent odour. It is mainly used as an antioxidant or chemical sterilant.[1] As a disulfite, it is chemically very similar to sodium metabisulfite, with which it is sometimes used interchangeably. Potassium metabisulfite has a monoclinic crystal structure.
It is used as a food additive, also known as E224.[3] It is restricted in use and may cause allergic reactions in some sensitive persons.[4]
Wineedit
Potassium metabisulfite is a common wine or must additive, in which it forms sulfur dioxide (SO2). Sulfur dioxide is a disinfectant. It also acts as a potent antioxidant, protecting both the color and delicate flavors of wine.
A high dose would be 3 grams of potassium metabisulfite per six-gallon bucket of must (yielding roughly 75 ppm of SO2) prior to fermentation; then 6 grams per six-gallon bucket (150 ppm of SO2) at bottling. Some countries regulate the SO2 content of wines.[5]
Winemaking equipment is sanitized by spraying with a 1% SO2 (2 tsp potassium metabisulfite per L) solution.
Beeredit
Potassium metabisulfite is sometimes used in the brewing industry to inhibit the growth of wild bacteria and fungi. This step is called 'stabilizing'. It is also used to neutralize monochloramine from tap water. It is used both by homebrewers and commercial brewers alike. It is not used as much for brewing beer, because the wort is almost always boiled, which kills most microorganisms.
Other usesedit
Potassium metabisulfite is sometimes added to lemon juice as a preservative.
Potassium metabisulfite is used in the textile industry for dyeing and cotton printing.
Potassium metabisulfite is sometimes used to precipitate gold from solution in aqua regia (as an alternative to sodium sulfite).
It is a component of certain photographic developers and solutions used in photographic processing, keeping active developing species from contact with oxygen.[6]
It is used as a bleaching agent in the production of coconut cream.
It is used in some pickles as a preservative.
It is used in tint etching iron-based metal samples for microstructural analysis.[7]
^Johnstone, H. F. (1946). "Sulfites and Pyrosulfites of the Alkali Metals". Inorganic Syntheses. Inorganic Syntheses. Vol. 2. pp. 162–167. doi:10.1002/9780470132333.ch49. ISBN9780470132333.
^Metcalfe, Dean D.; Simon, Ronald A. (2003). Food allergy: adverse reactions to food and food additives. Malden, MA: Wiley-Blackwell. pp. 324–339. ISBN978-0-632-04601-0.
^Gorman-McAdams, Mary (July 9, 2020). "The Truth About Sulfites in Wine & the Myths of Red Wine Headaches". The Kitchn. Retrieved February 10, 2024.
potassium, metabisulfite, k2s2o5, also, known, potassium, pyrosulfite, white, crystalline, powder, with, pungent, odour, mainly, used, antioxidant, chemical, sterilant, disulfite, chemically, very, similar, sodium, metabisulfite, with, which, sometimes, used, . Potassium metabisulfite K2S2O5 also known as potassium pyrosulfite is a white crystalline powder with a pungent odour It is mainly used as an antioxidant or chemical sterilant 1 As a disulfite it is chemically very similar to sodium metabisulfite with which it is sometimes used interchangeably Potassium metabisulfite has a monoclinic crystal structure Potassium metabisulfite Names Other names Potassium pyrosulfiteDipotassium disulfitePotassium metabisulphiteDipotassium disulphite Identifiers CAS Number 16731 55 8 Y 3D model JSmol Interactive image ChemSpider 26061 Y ECHA InfoCard 100 037 072 E number E224 preservatives PubChem CID 28019 RTECS number TT4920000 UNII 65OE787Q7W Y CompTox Dashboard EPA DTXSID1021293 InChI InChI 1S 2K H2O5S2 c 1 6 2 7 3 4 5 h H 1 2 H 3 4 5 q2 1 p 2 YKey RWPGFSMJFRPDDP UHFFFAOYSA L YInChI 1 2K H2O5S2 c 1 6 2 7 3 4 5 h H 1 2 H 3 4 5 q2 1 p 2Key RWPGFSMJFRPDDP NUQVWONBAF SMILES K K O S O S O O O Properties Chemical formula K 2O 5S 2 Molar mass 222 31 g mol 1 Appearance White crystalline powder Odor Pungent sulfur dioxide Density 2 34 g cm3 solid Melting point 190 C 374 F 463 K decomposes Solubility in water 450 g L 20 C Solubility Insoluble in ethanol Hazards Occupational safety and health OHS OSH Main hazards Irritant asthma risk GHS labelling Pictograms Signal word Danger Hazard statements H315 H318 H335 Precautionary statements P261 P264 P271 P280 P302 P352 P304 P340 P305 P351 P338 P310 P312 P321 P332 P313 P362 P403 P233 P405 P501 NFPA 704 fire diamond 100 Safety data sheet SDS ICSC 1175 Related compounds Other anions Potassium bisulfitePotassium sulfite Other cations Sodium metabisulfite Except where otherwise noted data are given for materials in their standard state at 25 C 77 F 100 kPa Y verify what is Y N Infobox references Contents 1 Preparation and reactions 2 Uses 2 1 Wine 2 2 Beer 2 3 Other uses 3 See also 4 ReferencesPreparation and reactions editMain article bisulfite Reactions Potassium metabisulfite can be prepared by treating a solution of potassium hydroxide with sulfur dioxide 2 2 SO2 2 KOH K2S2O5 H2O It decomposes at 190 C yielding potassium sulfite and sulfur dioxide K2S2O5 K2SO3 SO2Uses editIt is used as a food additive also known as E224 3 It is restricted in use and may cause allergic reactions in some sensitive persons 4 Wine edit Potassium metabisulfite is a common wine or must additive in which it forms sulfur dioxide SO2 Sulfur dioxide is a disinfectant It also acts as a potent antioxidant protecting both the color and delicate flavors of wine A high dose would be 3 grams of potassium metabisulfite per six gallon bucket of must yielding roughly 75 ppm of SO2 prior to fermentation then 6 grams per six gallon bucket 150 ppm of SO2 at bottling Some countries regulate the SO2 content of wines 5 Winemaking equipment is sanitized by spraying with a 1 SO2 2 tsp potassium metabisulfite per L solution Beer edit Potassium metabisulfite is sometimes used in the brewing industry to inhibit the growth of wild bacteria and fungi This step is called stabilizing It is also used to neutralize monochloramine from tap water It is used both by homebrewers and commercial brewers alike It is not used as much for brewing beer because the wort is almost always boiled which kills most microorganisms Other uses edit Potassium metabisulfite is sometimes added to lemon juice as a preservative Potassium metabisulfite is used in the textile industry for dyeing and cotton printing Potassium metabisulfite is sometimes used to precipitate gold from solution in aqua regia as an alternative to sodium sulfite It is a component of certain photographic developers and solutions used in photographic processing keeping active developing species from contact with oxygen 6 It is used as a bleaching agent in the production of coconut cream It is used in some pickles as a preservative It is used in tint etching iron based metal samples for microstructural analysis 7 It is used in aam papad as a preservative See also editCampden tabletReferences edit Barbera Jose Jimenez Metzger Adolf Wolf Manfred 2000 Sulfites Thiosulfates and Dithionitesl Chemistry Ullmann s Encyclopedia of Industrial Chemistry Weinheim Wiley VCH doi 10 1002 14356007 a25 477 ISBN 978 3527306732 Johnstone H F 1946 Sulfites and Pyrosulfites of the Alkali Metals Inorganic Syntheses Inorganic Syntheses Vol 2 pp 162 167 doi 10 1002 9780470132333 ch49 ISBN 9780470132333 List of E number food additives Metcalfe Dean D Simon Ronald A 2003 Food allergy adverse reactions to food and food additives Malden MA Wiley Blackwell pp 324 339 ISBN 978 0 632 04601 0 Gorman McAdams Mary July 9 2020 The Truth About Sulfites in Wine amp the Myths of Red Wine Headaches The Kitchn Retrieved February 10 2024 Potassium Metabisulfite Color Metallography 2011 05 04 Retrieved from https en wikipedia org w index php title Potassium metabisulfite amp oldid 1213407451, wikipedia, wiki, book, books, library,
