Diacetyl
362930
216782377
2008-06-03T05:00:32Z
ShelfSkewed
1152308
Disambiguate [[fatal]] to [[wiktionary:fatal]]
{{Chembox new
| Reference = <ref>''Merck Index'', 11th Edition, '''2946'''.</ref>
| ImageFileL1 = Diacetyl structure.png
| ImageSizeL1 = 100px
| ImageFileR1 = Diacetyl-3D-balls.png
| ImageSizeR1 = 120px
| IUPACName = 2,3-Butanedione
| OtherNames = Diacetyl<br>Biacetyl
| Section1 = {{Chembox Identifiers
| CASNo = 431-03-8
| PubChem = 650
| SMILES = CC(=O)C(C)=O
}}
| Section2 = {{Chembox Properties
| Formula = C<sub>4</sub>H<sub>6</sub>O<sub>2</sub>
| MolarMass = 86.0892 g/mol
| Appearance = Yellowish green liquid
| Density = 0.990 g/mL at 15 °C
| MeltingPt = -2 to -4 °C
| BoilingPt = 88 °C
| Solubility = Soluble in 4 parts
}}
| Section3 = {{Chembox Hazards
| ExternalMSDS = [https://fscimage.fishersci.com/msds/03275.htm External MSDS]
| MainHazards = Harmful, flammable
| FlashPt =
| Autoignition =
| RPhrases = {{R10}} {{R22}} {{R36}} {{R37}} {{R38}}
| SPhrases = {{S9}} {{S16}} {{S33}}
}}
}}
'''Diacetyl''' ([[IUPAC]] [[systematic name]]: '''butanedione''' or '''2,3-butanedione''') is a natural byproduct of [[fermentation (biochemistry)|fermentation]]. It is a [[Vicinal (chemistry)|vicinal]] [[diketone]] (two C=O groups, side-by-side) with the [[chemical formula|molecular formula]] C<sub>4</sub>H<sub>6</sub>O<sub>2</sub>. Diacetyl occurs naturally in alcoholic beverages and is added to some foods to impart a buttery flavor.
==In food products==
Diacetyl, along with [[acetoin]], is one of the compounds that gives [[butter]] its characteristic taste. Because of this, manufacturers of [[margarine|margarines]] or similar [[Vegetable fats and oils|oil]] based products typically add diacetyl and acetoin (along with [[beta carotene]] for the yellow color) to the final product, which would otherwise be tasteless.<ref>Pavia et al., Introduction to Organic Laboratory Techniques, 4th ed., ISBN 978-0-495-28069-9</ref>
==In alcoholic beverages==
At low levels in [[alcoholic beverage]]s, it contributes a slipperiness to the feel of the [[beer]] or [[wine]] in the mouth. As levels increase, it imparts a [[butter]]y or [[butterscotch]] flavor (butterscotch itself may be devoid of diacetyl).
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 [[decarboxylation|decarboxylated]] into diacetyl. The yeast then absorbs the diacetyl, and reduces the [[ketone]] groups to form [[acetoin]] and 2,3-butanediol, relatively flavorless compounds.
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.{{Fact|date=May 2007}}
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.<ref>JC Nielsen, M Richelieu. ''[http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=91089 Control of Flavor Development in Wine during and after Malolactic Fermentation by Oenococcus oeni]''. Appl Environ Microbiol. 1999 February; 65(2): 740–745.</ref><ref>B Martineau, T Henick-Kling, T Acree (1995). ''Reassessment of the Influence of Malolactic Fermentation on the Concentration of Diacetyl in Wines''. Am Soc Enol Viticulture.</ref>
==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.
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.
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.<ref> CBS News: [http://www.cbsnews.com/stories/2004/03/16/health/main606532.shtml Jury Gives Popcorn Worker $20M: Missouri Man Says Butter Flavor Vapor Ruined His Lungs] </ref> On [[July 19]], [[2005]], jurors awarded $2.7 million to another popcorn plant worker in [[Missouri]] for his claim of diacetyl-induced respiratory problems.<ref> International Flavors and Fragrances [http://sec.edgar-online.com/2005/08/05/0000051253-05-000020/Section10.asp SEC Annual Report Form 10K: Item 1: Legal Proceedings]. Filed August 5, 2005. </ref>
On [[July 26]], [[2006]], the [[Teamsters|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.<ref> [http://defendingscience.org/upload/Union%20Petition%20to%20CHAO%20on%20Diacetyl%20Signed.pdf UFCW and Teamsters Petition to OSHA]</ref> The petition was followed by a letter of support signed by more than thirty prominent scientists.<ref>[http://defendingscience.org/upload/Scientists%20Letter%20to%20OSHA%20on%20Diacetyl07262006.pdf Scientists Letter to Secretary Chao]</ref> The matter is under consideration.
There are currently two bills in the California Legislature to ban the use of diacetyl.<ref>[http://www.nytimes.com/2007/05/06/us/06butter.html?ex=1336104000&en=8d5a0800872c853f&ei=5124&partner=permalink&exprod=permalink Flavoring-Factory Illnesses Raise Inquiries], New York Times, May 6, 2007</ref><ref>[http://info.sen.ca.gov/pub/07-08/bill/sen/sb_0451-0500/sb_456_cfa_20070601_161435_sen_floor.html SB 456 Senate Bill - Bill Analysis]</ref><ref>[http://info.sen.ca.gov/pub/07-08/bill/asm/ab_0501-0550/ab_514_cfa_20070602_170841_asm_floor.html AB 514 Assembly Bill - Bill Analysis]</ref>
===Consumer safety===
Dr. Cecile Rose, [[pulmonary]] [[specialist]] at [[Denver]]'s [[National Jewish Medical and Research Center]], in a letter, warned [[Federal government of the United States|federal]] agencies or [[regulators]] that [[consumers]], not just [[factory]] [[workers]], are in [[danger]] of suffering the [[wiktionary:fatal|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]].<ref>[http://news.yahoo.com/s/ap/20070905/ap_on_he_me/popcorn_lung_consumer;_ylt=Apuf6TQn0o.P4GubPgYwzKGs0NUE Yahoo.com, Doctor warns consumers of popcorn fumes]</ref><ref>David Michaels. [http://thepumphandle.wordpress.com/2007/09/04/popcorn-lung-coming-to-your-kitchen-the-fda-doesnt-want-to-know/ Popcorn Lung Coming to Your Kitchen? The FDA Doesn’t Want to Know]</ref> However, the only sample data known-to-date is the case where a consumer, who ate at least two bags of buttery microwave popcorn daily for 10 years, became diagnosed with the same disease affecting workers exposed to the substance, [[bronchiolitis obliterans]].<ref>Reuters New Report: [http://uk.reuters.com/article/healthNews/idUKN0524254120070905 FDA to probe popcorn link in man's lung disease].</ref> His lung problems were linked to breathing the vapors; although rare, the reported man's kitchen also had diacetyl levels comparable to those in popcorn plants.<ref>Reuters New Report: [http://uk.reuters.com/article/healthNews/idUKN0524254120070905 FDA to probe popcorn link in man's lung disease].</ref>
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]].<ref>Weaver Popcorn Company. Press Release: [http://www.popweaver.com/NoDiacetylPressRelease.pdf Pop Weaver introduces first microwave popcorn with flavoring containing no diacetyl].</ref> Weaver makes the [[Trail's End]] brand of popcorn sold by the [[Boy Scouts of America]]. A [[ConAgra Foods|ConAgra]] spokesperson has said it will do the same in a year,<ref>Reuters News Report[http://www.usatoday.com/money/industries/food/2007-09-05-popcorn-lung_N.htm ConAgra to drop popcorn chemical linked to lung ailment]</ref> and is working to remove the ingredient from its popcorn products. <ref>[http://newsok.com/article/3160305/1193790238 Microwave popcorn makers removing threatening chemical | NewsOK.com<!-- Bot generated title -->]</ref>
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." <ref>Reuters News Report [http://www.reuters.com/article/domesticNews/idUSN0524254120070905?sp=true Reuters- FDA to probe popcorn link in man's lung disease]</ref>
=== EU regulation ===
The EU Commission has declared that diacetyl is legal for use as a flavouring substance in all EU states. <ref>http://www.fsai.ie/legislation/food/eu_docs/Flavourings/Dir99.217.pdf</ref> As a diketone, diacetyl falls with the EU's flavouring classification Flavouring Group Evaluation 11(FGE.11). A Scientific Panel of the EU Commission evaluated six flavouring substances (not including diacetyl) from FGE.11 in 2004.<ref>http://www.efsa.europa.eu/EFSA/Scientific_Opinion/afc_opinionflav_ej166_en1.pdf</ref> As part of this study, the Panel reviewed available studies on several other flavourings in FEG.11, including diacetyl. Based on the available data, the Panel reiterated the finding that there were no safety concerns for diacetyl's use as a flavouring. As a result of the Panel's 2004 study, [[acetylacetone]] (FL 07.191) was found to be genotoxic in vitro and in vivo, and was therefore deleted from the register of permitted flavouring substances.<ref>http://eur-lex.europa.eu/LexUriServ/site/en/oj/2005/l_128/l_12820050521en00730076.pdf</ref> Recently, the [[European Food Safety Authority]] (EFSA), the EU's food safety regulatory body, stated that that its scientific panel on food additives and flavourings (AFC) was evaluating diacetyl along with other flavourings as part of a larger study. "The experts of the EFSA AFC panel and its working group on food additives will look at this issue to see if new scientific evidence is available that may require further actions. If the experts conclude that consumer exposure to diacetyl can reach levels well above those considered as safe and, that a possible health risk for consumers cannot be excluded when inhaling diacetyl, EFSA will give priority to the re-evaluation of this substance and provide detailed scientific advice."<ref>[http://www.foodnavigator.com/news/ng.asp?n=81014-conagra-popcorn-lung-diacetyl Europe takes 'wait-and-see' stance on diacetyl flavouring<!-- Bot generated title -->]</ref>
==See also==
* [[Bronchiolitis obliterans]]
==References==
{{reflist|2}}
==External links==
*[http://www.diacetyl.dk/index1.asp Research project on diacetyl reduction during beer fermentation]*[http://www2.siri.org/msds/tox/f/q34/q996.html Toxicology data]
*NIOSH Alert: [http://www.cdc.gov/niosh/docs/2004-110/ 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.
*[http://defendingscience.org/case_studies/A-Case-of-Regulatory-Failure-Popcorn-Workers-Lung.cfm A Case of Regulatory Failure - Popcorn Workers Lung], from ''[[SKAPP|www.defendingscience.org]]''.
*[http://www.defendingscience.org/case_studies/Diacetyl-Press-Release-July.cfm Scientists Urge Secretary of Labor to Protect Workers from Diacetyl], a press release from ''[[SKAPP|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.
*[http://www.washingtonpost.com/wp-dyn/content/article/2007/05/06/AR2007050601089.html Flavoring suspected in illness], Washington Post, May 7, 2007.
*[http://www.cdc.gov/niosh/ipcsneng/neng1168.html NIOSH International Safety Card for 2,3-butanedione]
*[http://www.cdc.gov/niosh/topics/flavorings/ National Institute for Occupational Safety and Health - Flavorings-Related Lung Disease]
*[http://www.ific.org/publications/qa/diactylqa.cfm IFIC - Diacetyl]
*[http://www.popcornfacts.com ConAgra Foods, Inc. - Diacetyl]
[[Category:Ketones]]
[[Category:Flavors]]
[[Category:Popcorn]]
[[Category:Occupational safety and health]]
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[[fr:Diacétyle]]
[[lv:Diacetils]]
[[pl:Biacetyl]]
[[fi:2,3-butaanidioni]]
[[nl:butaandion]]