Potassium bromate

Last updated
Potassium bromate
Potassium bromate.png
Potassium-3D.png
Bromate-3D-vdW.png
Bromicnan draselny.JPG
Names
IUPAC name
Potassium bromate
Other names
  • Potassium bromate(V)
  • Bromic acid, potassium salt
Identifiers
3D model (JSmol)
ChEBI
ChEMBL
ChemSpider
ECHA InfoCard 100.028.936 OOjs UI icon edit-ltr-progressive.svg
EC Number
  • 231-829-8
15380
KEGG
PubChem CID
RTECS number
  • EF8725000
UNII
UN number 1484
  • InChI=1S/BrHO3.K/c2-1(3)4;/h(H,2,3,4);/q;+1/p-1 Yes check.svgY
    Key: OCATYIAKPYKMPG-UHFFFAOYSA-M Yes check.svgY
  • InChI=1/BrHO3.K/c2-1(3)4;/h(H,2,3,4);/q;+1/p-1
    Key: OCATYIAKPYKMPG-REWHXWOFAM
  • [K+].[O-]Br(=O)=O
Properties
KBrO
3
Molar mass 167.00 g/mol
Appearancewhite crystalline powder
Density 3.27 g/cm³
Melting point 350 °C (662 °F; 623 K)
Boiling point 370 °C (698 °F; 643 K) (decomposes)
3.1 g/100 mL (0 °C)
6.91 g/100 mL (20 °C)
13.3 g/100 mL (40 °C)
49.7 g/100 mL (100 °C)
Solubility Insoluble in acetone
−52.6·10−6 cm³/mol
Structure
hexagonal
Thermochemistry
−342.5 kJ/mol
Hazards
GHS labelling:
GHS-pictogram-rondflam.svg GHS-pictogram-skull.svg GHS-pictogram-silhouette.svg
Danger
H271, H301, H350
P201, P202, P210, P220, P221, P264, P270, P280, P281, P283, P301+P310, P306+P360, P308+P313, P321, P330, P370+P378, P371+P380+P375, P405, P501
NFPA 704 (fire diamond)
NFPA 704.svgHealth 3: Short exposure could cause serious temporary or residual injury. E.g. chlorine gasFlammability 0: Will not burn. E.g. waterInstability 2: Undergoes violent chemical change at elevated temperatures and pressures, reacts violently with water, or may form explosive mixtures with water. E.g. white phosphorusSpecial hazard OX: Oxidizer. E.g. potassium perchlorate
3
0
2
OX
Flash point Non-flammable
Lethal dose or concentration (LD, LC):
157 mg/kg (oral, rat) [1]
Safety data sheet (SDS) "ICSC 1115".
Related compounds
Other anions
Potassium chlorate
Potassium iodate
Other cations
Sodium bromate
Calcium bromate
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
X mark.svgN  verify  (what is  Yes check.svgYX mark.svgN ?)

Potassium bromate (KBrO
3
) is a bromate of potassium and takes the form of white crystals or powder. It is a strong oxidizing agent.

Contents

Preparation

Potassium bromate is produced when bromine is passed through a hot solution of potassium hydroxide. This first forms unstable potassium hypobromite, which quickly disproportionates into bromide and bromate: [2]

3 BrO
2 Br
+ BrO
3

Electrolysis of potassium bromide solutions will also give bromate. Both processes are analogous to those used in the production of chlorates.[ citation needed ]

Potassium bromate is readily separated from the potassium bromide present in both methods owing to its much lower solubility; when a solution containing potassium bromate and bromide is cooled to 0°C, nearly all bromate will precipitate, while nearly all of the bromide will stay in solution. [2]

Uses in baking

Potassium bromate is typically used in the United States as a flour improver (E number E924). It acts to strengthen the dough and to allow higher rising. It is an oxidizing agent, and under the right conditions, will be completely reduced to bromide in the baking process. [3] [4] However, if too much is added, or if the bread is not baked long enough or not at a high enough temperature, then a residual amount will remain, which may be harmful if consumed. [4]

Potassium bromate might also be used in the production of malt barley, but under certain safety conditions prescribed by the U.S. Food and Drug Administration (FDA), including labeling standards for the finished malt barley product. [5] It is a very powerful oxidizer (electrode potential   = 1.5 volts, similar to potassium permanganate).[ citation needed ]

Regulation

In October 2023, California passed a law that banned the manufacture, sale, and distribution of potassium bromate (along with three other additives: brominated vegetable oil, propylparaben, and Red 3). This is the first law in the U.S. to ban it, and will possibly have nationwide effects. [6]

Potassium bromate has been banned from food products in the European Union, Argentina, Brazil, [7] Canada, Nigeria, South Korea, and Peru. It was banned in Sri Lanka in 2001, [8] China in 2005, [9] and India in 2016, [10] but it is allowed in most of the United States. As of May 2023, the U.S. state of New York is considering banning the use of potassium bromate. [11] California plans to ban the use of potassium bromate in food starting in 2027, following a bill signed into law in October 2023. [12] [13]

Potassium bromate is classified as a category 2B carcinogen by the IARC. [14] The FDA allowed the use of bromate before the Delaney clause of the Food, Drug, and Cosmetic Act – which bans potentially carcinogenic substances – went into effect in 1958. However, since 1991, the FDA has urged bakers to voluntarily stop using it but has not mandated a ban and some bakers still use it. In California, a warning label is required when bromated flour is used. [15] Japanese baked goods manufacturers stopped using potassium bromate voluntarily in 1980; however, Yamazaki Baking resumed its use in 2005, claiming it had new production methods to reduce the amount of the chemical which remained in the final product. [16]

Related Research Articles

<span class="mw-page-title-main">Aspartame</span> Artificial non-saccharide sweetener

Aspartame is an artificial non-saccharide sweetener 200 times sweeter than sucrose and is commonly used as a sugar substitute in foods and beverages. It is a methyl ester of the aspartic acid/phenylalanine dipeptide with brand names NutraSweet, Equal, and Canderel. Aspartame was approved by the US Food and Drug Administration (FDA) in 1974, and then again in 1981, after approval was revoked in 1980.

<span class="mw-page-title-main">Bromine</span> Chemical element, symbol Br and atomic number 35

Bromine is a chemical element; it has symbol Br and atomic number 35. It is a volatile red-brown liquid at room temperature that evaporates readily to form a similarly coloured vapour. Its properties are intermediate between those of chlorine and iodine. Isolated independently by two chemists, Carl Jacob Löwig and Antoine Jérôme Balard, its name was derived from the Ancient Greek βρῶμος (bromos) meaning "stench", referring to its sharp and pungent smell.

<span class="mw-page-title-main">Potassium bromide</span> Ionic compound (KBr)

Potassium bromide (KBr) is a salt, widely used as an anticonvulsant and a sedative in the late 19th and early 20th centuries, with over-the-counter use extending to 1975 in the US. Its action is due to the bromide ion. Potassium bromide is used as a veterinary drug, in antiepileptic medication for dogs.

<span class="mw-page-title-main">Sodium nitrite</span> Chemical compound

Sodium nitrite is an inorganic compound with the chemical formula NaNO2. It is a white to slightly yellowish crystalline powder that is very soluble in water and is hygroscopic. From an industrial perspective, it is the most important nitrite salt. It is a precursor to a variety of organic compounds, such as pharmaceuticals, dyes, and pesticides, but it is probably best known as a food additive used in processed meats and (in some countries) in fish products.

<span class="mw-page-title-main">Brominated vegetable oil</span> Type of vegetable oil used in the soft drinks industry

Brominated vegetable oil (BVO) is a complex mixture of plant-derived triglycerides that have been modified by atoms of the element bromine bonded to the fat molecules. Brominated vegetable oil is used to help emulsify citrus-flavored soft drinks, preventing them from separating during distribution. Brominated vegetable oil has been used by the soft drink industry since 1931, generally at a level of about 8 ppm.

Hydrobromic acid is an aqueous solution of hydrogen bromide. It is a strong acid formed by dissolving the diatomic molecule hydrogen bromide (HBr) in water. "Constant boiling" hydrobromic acid is an aqueous solution that distills at 124.3 °C (255.7 °F) and contains 47.6% HBr by mass, which is 8.77 mol/L. Hydrobromic acid is one of the strongest mineral acids known.

<span class="mw-page-title-main">White bread</span> Type of bread made from white wheat flour

White bread typically refers to breads made from wheat flour from which the bran and the germ layers have been removed from the whole wheatberry as part of the flour grinding or milling process, producing a light-colored flour.

Wheat flour is a powder made from the grinding of wheat used for human consumption. Wheat varieties are called "soft" or "weak" if gluten content is low, and are called "hard" or "strong" if they have high gluten content. Hard flour, or bread flour, is high in gluten, with 12% to 14% gluten content, and its dough has elastic toughness that holds its shape well once baked. Soft flour is comparatively low in gluten and thus results in a loaf with a finer, crumbly texture. Soft flour is usually divided into cake flour, which is the lowest in gluten, and pastry flour, which has slightly more gluten than cake flour.

<span class="mw-page-title-main">Erythrosine</span> Iodo-derivative of fluorone used as a pink dye

Erythrosine, also known as Red No. 3, is an organoiodine compound, specifically a derivative of fluorone. It is a pink dye which is primarily used for food coloring. It is the disodium salt of 2,4,5,7-tetraiodofluorescein. Its maximum absorbance is at 530 nm in an aqueous solution, and it is subject to photodegradation.

<span class="mw-page-title-main">Bromate</span> Ion, and compounds containing the ion

The bromate anion, BrO
3
, is a bromine-based oxoanion. A bromate is a chemical compound that contains this ion. Examples of bromates include sodium bromate,, and potassium bromate,.

<span class="mw-page-title-main">Sodium bromate</span> Chemical compound

Sodium bromate, the inorganic compound with the chemical formula of NaBrO3, is the sodium salt of bromic acid. It is a strong oxidant.

<span class="mw-page-title-main">Azodicarbonamide</span> Chemical compound

Azodicarbonamide, ADCA, ADA, or azo(bis)formamide, is a chemical compound with the molecular formula C2H4O2N4. It is a yellow to orange-red, odorless, crystalline powder. It is sometimes called a 'yoga mat' chemical because of its widespread use in foamed plastics. It was first described by John Bryden in 1959.

<span class="mw-page-title-main">Propylparaben</span> Chemical compound

Propylparaben is the n-propyl ester of p-hydroxybenzoic acid. It occurs as a natural substance found in many plants and some insects. Additionally, it can be manufactured synthetically for use in cosmetics, pharmaceuticals, and foods. It is a member of the class of parabens and can be used as a preservative in many water-based cosmetics, such as creams, lotions, shampoos, and bath products. As a food additive, it has an E number, which is E216.

<span class="mw-page-title-main">Potassium iodate</span> Chemical compound

Potassium iodate (KIO3) is an ionic inorganic compound with the formula KIO3. It is a white salt that is soluble in water.

<span class="mw-page-title-main">Hypobromite</span> Ion, and compounds containing the ion

The hypobromite ion, also called alkaline bromine water, is BrO. Bromine is in the +1 oxidation state. The Br–O bond length is 1.82 Å. Hypobromite is the bromine compound analogous to hypochlorites found in common bleaches, and in immune cells. In many ways, hypobromite functions in the same manner as hypochlorite, and is also used as a germicide and antiparasitic in both industrial applications, and in the immune system.

Bromine compounds are compounds containing the element bromine (Br). These compounds usually form the -1, +1, +3 and +5 oxidation states. Bromine is intermediate in reactivity between chlorine and iodine, and is one of the most reactive elements. Bond energies to bromine tend to be lower than those to chlorine but higher than those to iodine, and bromine is a weaker oxidising agent than chlorine but a stronger one than iodine. This can be seen from the standard electrode potentials of the X2/X couples (F, +2.866 V; Cl, +1.395 V; Br, +1.087 V; I, +0.615 V; At, approximately +0.3 V). Bromination often leads to higher oxidation states than iodination but lower or equal oxidation states to chlorination. Bromine tends to react with compounds including M–M, M–H, or M–C bonds to form M–Br bonds.

The artificial sweetener aspartame has been the subject of several controversies since its initial approval by the U.S. Food and Drug Administration (FDA) in 1974. The FDA approval of aspartame was highly contested, beginning with suspicions of its involvement in brain cancer, alleging that the quality of the initial research supporting its safety was inadequate and flawed, and that conflicts of interest marred the 1981 approval of aspartame, previously evaluated by two FDA panels that concluded to keep the approval on hold before further investigation. In 1987, the U.S. Government Accountability Office concluded that the food additive approval process had been followed properly for aspartame. The irregularities fueled a conspiracy theory, which the "Nancy Markle" email hoax circulated, along with claims—counter to the weight of medical evidence—that numerous health conditions are caused by the consumption of aspartame in normal doses.

<span class="mw-page-title-main">Dough conditioner</span>

A dough conditioner, flour treatment agent, improving agent or bread improver is any ingredient or chemical added to bread dough to strengthen its texture or otherwise improve it in some way. Dough conditioners may include enzymes, yeast nutrients, mineral salts, oxidants and reductants, bleaching agents and emulsifiers. They are food additives combined with flour to improve baking functionality. Flour treatment agents are used to increase the speed of dough rising and to improve the strength and workability of the dough.

<span class="mw-page-title-main">Yamazaki Baking</span> Japanese food company

The Yamazaki Baking Company, Ltd. is a Japanese food company and the world's largest bread-baking corporation, that makes bread, bakery products and confectionery. It was established by Tojuro Iijima in Japan on 9 March 1948 and started mass production of bread in 1955, and is still controlled by the Iijima family; Nobuhiro Iijima is the third generation of the family to lead the company.

Calcium bromate, Ca(BrO3)2, is a calcium salt of bromic acid. It is most commonly encountered as the monohydrate, Ca(BrO3)2•H2O.

References

  1. "Potassium bromate". chem.sis.nlm.nih.gov. ChemIDplus. U.S. National Institutes of Health. RN 7758-01-2.
  2. 1 2 Synthesis, separation, and purification of KBr and KBrO (PDF). Pre-Labs (course notes). Advanced Placement Chemistry. Harvard-Westlake School. Archived from the original (PDF) on 16 May 2017. Retrieved 14 September 2016 via Harvard-Westlake School (hwscience.com).
  3. "Volume 13, Series 6, page 3136". Federal Register (compendium). Office of the Federal Register, National Archives and Records Service. Washington, DC: General Services Administration. 1948 via Google Books.
  4. 1 2 Kurokawa, Y.; Maekawa, A.; Takahashi, M.; Hayashi, Y. (1 July 1990). "Toxicity and carcinogenicity of potassium bromate – a new renal carcinogen". Environmental Health Perspectives . 87: 309–335. doi:10.1289/ehp.9087309. ISSN   0091-6765. PMC   1567851 . PMID   2269236.
  5. "Potassium Bromate". Food Additives Permitted for Direct Addition to Food for Human Consumption (laws & regulations). U.S. Code of Federal Regulations. U.S. Food and Drug Administration. section 172.730 via ecfr.gov.
  6. California isn’t banning Skittles, but four additives will be removed by Marlene Cimons, Washington Post, Oct. 11, 2023. The article notes that Red dye No. 3, bromated vegetable oil, potassium bromate and propyl paraben all have been linked to risk of cancer and hyperactivity in children.
  7. "Dispõe sobre o uso do bromato de potássio na farinha e nos produtos de panificação" [Regarding the use of potassium bromate in flour and bakery products] (in Portuguese). c. 2001 via planalto.gov.br.
  8. "[title not cited]". E‑Law Advocate. No. 4. Bridges Across Borders. (2001). Archived from the original on 2018-05-16. Retrieved 2006-10-10. Environmental Law Alliance Worldwide[ citation not found ]
  9. "Importer halts unsafe potato chips from the U.S." China Daily . 7 December 2007. Retrieved 2023-02-21 via chinadaily.com.cn.
  10. "India bans use of cancer-causing additive, potassium bromate, in bread, other food". The Times of India . 21 June 2016 [20 June 2016]. Retrieved 20 June 2016 via timesofindia.indiatimes.com.
  11. Smith, Dana G. (13 April 2023). "Two states have proposed bans on common food additives linked to health concerns". The New York Times . Retrieved 23 May 2023 via nytimes.com.
  12. "AB-418 The California Food Safety Act". ca.gov.
  13. "California becomes first U.S. state to ban 4 potentially harmful chemicals in food". CNN . 10 October 2023.
  14. Potassium bromate (group 2B) (Report). IARC Summaries & Evaluations. Vol. 73. International Agency for Research on Cancer (IARC). 73-17 via inchem.org.
  15. "Bromate meets the criteria for listing". CRNR notices. oehha.ca.gov. Proposition 65. California Office of Environmental Health Hazard Assessment. Archived from the original on 2013-12-03.
  16. Kawo, Kuro; et al. (c. 1990). "Japan's Yamazaki Baking to use potassium bromate in bread". AsiaPulse News. Cited by
    Duvvuri, Shreemathi; Panchagnula, Shobharani (September–October 2016). "Analysis of potassium iodate and potassium bromate in bakery products by electro-analytical techniques" (PDF). International Journal of Trend in Research and Development. 3 (5): 412–413. ISSN   2394-9333 via ijtrd.com.