Diacetyl[1]
IUPAC name	2,3-Butanedione
Other names	Diacetyl Biacetyl
Identifiers
CAS number	431-03-8
PubChem	650
SMILES	CC(=O)C(C)=O
Properties
Molecular formula	C4H6O2
Molar mass	86.0892 g/mol
Appearance	Yellowish green liquid
Density	0.990 g/mL at 15 °C
Melting point	-2 to -4 °C Image File history File links Size of this preview: 502 × 599 pixelsFull resolution (867 × 1035 pixel, file size: 8 KB, MIME type: image/png) File historyClick on a date/time to view the file as it appeared at that time. ... IUPAC nomenclature is a system of naming chemical compounds and of describing the science of chemistry in general. ... CAS registry numbers are unique numerical identifiers for chemical compounds, polymers, biological sequences, mixtures and alloys. ... PubChem is a database of chemical molecules. ... The simplified molecular input line entry specification or SMILES is a specification for unambiguously describing the structure of chemical molecules using short ASCII strings. ... A chemical formula is a concise way of expressing information about the atoms that constitute a particular chemical compound. ... Molar mass is the mass of one mole of a chemical element or chemical compound. ... For other uses, see Density (disambiguation). ... The melting point of a crystalline solid is the temperature range at which it changes state from solid to liquid. ...
Boiling point	88 °C Italic text This article is about the boiling point of liquids. ...
Solubility in water	Soluble in 4 parts
Hazards
MSDS	External MSDS
Main hazards	Harmful, flammable
R-phrases	R10 R22 R36 R37 R38
S-phrases	S9 S16 S33
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references

Diacetyl (IUPAC systematic name: butanedione or 2,3-butanedione) is a natural byproduct of fermentation. It is a vicinal diketone (two C=O groups, side-by-side) with the molecular formula C₄H₆O₂. Solubility is a chemical property referring to the ability for a given substance, the solute, to dissolve in a solvent. ... Impact from a water drop causes an upward rebound jet surrounded by circular capillary waves. ... This page meets Wikipedias criteria for speedy deletion. ... The examples and perspective in this article or section may not represent a worldwide view. ... R-phrases are defined in Annex III of European Union Directive 67/548/EEC: Nature of special risks attributed to dangerous substances and preparations. ... S-phrases are defined in Annex IV of European Union Directive 67/548/EEC: Safety advice concerning dangerous substances and preparations. ... In chemistry, the standard state of a material is its state at 1 bar (100 kilopascals) and 25 degrees Celsius (298. ... The International Union of Pure and Applied Chemistry (IUPAC) is an international non-governmental organization devoted to the advancement of chemistry. ... There are millions of possible objects that can be described in science, too many to create common names for every one. ... It has been suggested that this article or section be merged with Fermentation (food). ... In chemistry vicinal stands for any two functional groups bonded to two adjacent carbon atoms. ... A diketone is a molecule containing two carbonyl groups. ... A chemical formula is a concise way of expressing information about the atoms that constitute a particular chemical compound. ...

In alcoholic beverages

At low levels in alcoholic beverages, it contributes a slipperiness to the feel of the beer or wine in the mouth. As levels increase, it imparts a buttery or butterscotch flavor (butterscotch itself may be devoid of diacetyl). Alcoholic beverages. ... For other uses, see Beer (disambiguation). ... For other uses, see Wine (disambiguation). ... For other uses, see Butter (disambiguation). ... Americas Got Talent, see Butterscotch (singer). ...

It is produced during fermentation as a byproduct of valine synthesis. During this synthesis yeast produces α-acetolactate, which escapes the cell and is spontaneously decarboxylated into diacetyl. The yeast then adsorbs the diacetyl, and reduces the ketone groups to form acetoin and 2,3-butanediol, relatively flavorless compounds. Valine is an amino acid that cannot be synthesized by humans, so it is considered an essential amino acid for human life. ... A Decarboxylation is any chemical reaction in which a carboxyl group (-COOH) is split off from a compound as carbon dioxide (CO2). ... Ketone group A ketone (pronounced as key tone) is either the functional group characterized by a carbonyl group (O=C) linked to two other carbon atoms or a chemical compound that contains this functional group. ... 3-Hydroxybutanone, also known as acetoin or acetyl methyl carbinol, is a chemical compound composed of carbon, hydrogen and oxygen. ...

Beer sometimes undergoes a diacetyl rest, which entails elevating temperature slightly for two or three days after fermentation is complete, to allow the yeast to absorb the diacetyl it produced earlier in the fermentation cycle. The makers of some wines, such as chardonnay, deliberately promote the production of diacetyl because of the feel and flavors it imparts. It is present in many California chardonnays known as "Butter Bombs," although there is a growing trend back toward the more traditional French styles.^{[citation needed]} Oak-aged Chardonnay is particularly popular in the United States. ...

Concentrations from 0.005 mg/L to 1.7 mg/L were measured in chardonnay wines, and the amount needed for the flavor to be noticed is at least 0.2 mg/l.^[2][3]

Safety

Worker safety

The United States National Institute for Occupational Safety and Health has suggested that diacetyl, when used in artificial butter flavoring (as used in many consumer foods), may be hazardous when heated and inhaled over a long period. The National Institute for Occupational Safety and Health (NIOSH) is the United States federal agency responsible for conducting research and making recommendations for the prevention of work-related injury and illness. ...

Workers in several factories that manufacture artificial butter flavoring have been diagnosed with bronchiolitis obliterans, a rare and serious disease of the lungs. The cases found have been mainly in young, healthy, non-smoking males. There are no known cures for bronchiolitis obliterans except for lung transplantation. Bronchiolitis obliterans is a disease of the lungs in which the bronchioles are plugged with granulation tissue. ... The heart and lungs (from an older edition of Grays Anatomy) The lung is an organ belonging to the respiratory system and interfacing to the circulatory system of air-breathing vertebrates. ... Bronchiolitis obliterans is a disease of the lungs in which the bronchioles are plugged with granulation tissue. ...

While several authorities have called the disease "Popcorn Worker's Lung," a more accurate term suggested by other doctors may be more appropriate, since the disease can occur in any industry working with diacetyl: diacetyl-induced bronchiolitis obliterans.

After the workers filed a lawsuit against the manufacturers, the United States Environmental Protection Agency began an investigation into the chemical properties of microwave popcorn butter flavoring. In March 2004, former microwave popcorn plant employee Eric Peoples, of Joplin, Missouri, was awarded $20 million for permanent lung-injuries sustained while on the job.^[4] On July 19, 2005, jurors awarded $2.7 million to another popcorn plant worker in Missouri for his claim of diacetyl-induced respiratory problems.^[5] EPA redirects here. ... Joplin is a city located in parts of southern Jasper County and northern Newton County in the southwestern corner of Missouri. ... is the 200th day of the year (201st in leap years) in the Gregorian calendar. ... Year 2005 (MMV) was a common year starting on Saturday (link displays full calendar) of the Gregorian calendar. ... Official language(s) English Capital Jefferson City Largest city Kansas City Largest metro area St Louis[1] Area  Ranked 21st  - Total 69,709 sq mi (180,693 km²)  - Width 240 miles (385 km)  - Length 300 miles (480 km)  - % water 1. ...

On July 26, 2006, the International Brotherhood of Teamsters and the United Food and Commercial Workers petitioned the U.S. Occupational Safety and Health Administration to promulgate an emergency temporary standard to protect workers from the deleterious health effects of inhaling diacetyl vapors.^[6] The petition was followed by a letter of support signed by more than thirty prominent scientists.^[7] The matter is under consideration. is the 207th day of the year (208th in leap years) in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... The International Brotherhood of Teamsters (IBT), formerly known by the name International Brotherhood of Teamsters, Chauffeurs, Warehousemen and Helpers of America, is one of the largest labor unions in the United States. ... The United Food and Commercial Workers International Union is a labor union representing approximately 1. ... OSHA logo The United States Occupational Safety and Health Administration (OSHA) is an agency of the United States Department of Labor. ...

There are currently two bills in the California Legislature to ban the use of diacetyl.^[8][9][10]

Consumer safety

Dr. Cecile Rose, pulmonary specialist at Denver's National Jewish Medical and Research Center, in a letter, warned federal agencies or regulators that consumers, not just factory workers, are in danger of suffering the fatal popcorn lung disease from buttery flavoring fumes in microwave popcorn. David Michaels of the George Washington University School of Public Health first published Rose's letter on his blog.^[11][12] However, these claims have no official testing to prove that there is any risk associated with consumption of microwave popcorn. The heart and lungs (from an older edition of Grays Anatomy) The lung is an organ belonging to the respiratory system and interfacing to the circulatory system of air-breathing vertebrates. ... For the Italian comics character with this name, see Lo Sconosciuto Most general, a specialist is a person which are able to solve some predefined class of problems. ... This article refers to the state capital of Colorado. ... National Jewish Medical and Research Center is a research institute specializing in respiratory, immune and allergic research and treatment. ... This article describes the government of the United States. ... In economics, consumers are individuals or households that consume goods and services generated within the economy. ... This article or section does not cite any references or sources. ... In classical economics and all micro-economics labour is one of three factors of production, the others being land and capital. ... Wikipedia does not yet have an article with this exact name. ... FATAL (Originally short for Fantasy Adventure To Adult Lechery, but later changed to From Another Time, Another Land) is a tabletop role-playing game created by Byron Hall. ... Human respiratory system The lungs flank the heart and great vessels in the chest cavity. ... This article is about the medical term. ... This article deals with a type of bread roll. ... Category: ... This article is about the type of Electromagnetic radiation. ... The George Washington University (GW), is a private, coeducational university located in the Foggy Bottom neighborhood of Washington, D.C. The school was founded in 1821 as The Columbian College in the District of Columbia by Baptist ministers using funds bequeathed by George Washington. ... To meet Wikipedias quality standards, this article or section may require cleanup. ...

At least one heavy popcorn consumer has been diagnosed with the same disease affecting workers exposed to the substance, bronchiolitis obliterans.^[13] Bronchiolitis obliterans is a disease of the lungs in which the bronchioles are plugged with granulation tissue. ...

The Flavor and Extract Manufacturers on September 4, 2007, recommended reduction of diacetyl in butter flavorings. The Weaver Popcorn Company of Indianapolis has replaced the butter flavoring with a new ingredient.^[14] Weaver makes the Trail's End brand of popcorn sold by the Boy Scouts of America. ConAgra promises to do the same in a year.^[15] ConAgra Foods also is removing the ingredient from its popcorn products. For other uses, see Butter (disambiguation). ... The Indianapolis skyline Indianapolis is the capital of the U.S. state of Indiana. ... This article is being considered for deletion in accordance with Wikipedias deletion policy. ... Trails End is a brand of popcorn produced by the Weaver Popcorn Company that is provided to Cub Scouts and Boy Scouts in order to assist them with fundraising. ... For the Boy Scouting program within the BSA, see Boy Scouting (Boy Scouts of America). ... ConAgra Foods, Inc. ...

In a Reuters story dated September 5, 2007, writer Julie Steenhuysen quoted the spokeswoman for ConAgra Foods Inc, maker of Orville Redenbacher and Act II microwave popcorn brands, saying "it will drop diacetyl from its butter-flavored microwave popcorn in the near future." ^[16] Reuters Group plc (LSE: RTR and NASDAQ: RTRSY); pronounced is known as a financial market data provider and a news service that provides reports from around the world to newspapers and broadcasters. ... An image of Orville Redenbacher on a popcorn container Image:Bci oriville 1. ...

EU Regulation

The EU Commission has declared that diketones (for example acetylacetone, CH₃COCH₂COCH₃) are like dialcohols and hydroxyketones in that they are in vitro and in vivo genotoxic chemical substances and therefore have been forbidden as nutrition additives since 2005.^[17] The European Commission (formally the Commission of the European Communities) is the executive of the European Union. ... A diketone is a molecule containing two carbonyl groups. ... R-phrases , S-phrases , , , Flash point 34 °C Autoignition temperature 340 °C Explosive limits 2. ... Ethylene glycol, a simple diol A diol or glycol is a chemical compound containing two hydroxyl groups (-OH groups). ... Wiktionary has a definition of: In vitro In vitro (Latin: within glass) means within a test tube, or, more generally, outside a living organism or cell. ... In vivo (Latin for (with)in the living). ... Categories: Move to Wiktionary | Biochemistry stubs ... Food additives are substances added to food to preserve flavor or improve its taste and appearance. ...

As diacetyl is a diketone (in fact the simplest) it may eventually be subject to this EU regulation.^{[citation needed]}

See also

• Bronchiolitis obliterans

Bronchiolitis obliterans is a disease of the lungs in which the bronchioles are plugged with granulation tissue. ...

References

External links

• [1] Questions and Answers about Diacetyl
• Facts about Microwave Popcorn and Diacetyl
• Toxicology data
• NIOSH Alert: Preventing Lung Disease and Workers who Use or Make Flavorings
• Harber, Philip; Saechao, Kaochoy; & Boomus, Catherine. Diacetyl-induced lung disease. Toxicological Reviews 2006;vol 25(4):261-72.
• A Case of Regulatory Failure - Popcorn Workers Lung, from www.defendingscience.org.
• Scientists Urge Secretary of Labor to Protect Workers from Diacetyl, a press release from defendingscience.org. Links to studies on the health effects of diacetyl, and to a variety of related documents including the recent OSHA petition and the scientists' letter of support may be found here.
• Flavoring suspected in illness, Washington Post, May 7, 2007.
• NIOSH International Safety Card for 2,3-butanedione