Everything about Diacetyl totally explained
| Section2 =
| Section3 =
| SPhrases =
}}
}}
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 C
4H
6O
2. 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
margarines or similar
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.
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).
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 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's a growing trend back toward the more traditional French styles.
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.
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. On
July 19,
2005, jurors awarded $2.7 million to another popcorn plant worker in
Missouri for his claim of diacetyl-induced respiratory problems.
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. The petition was followed by a letter of support signed by more than thirty prominent scientists. The matter is under consideration.
There are currently two bills in the California Legislature to ban the use of diacetyl.
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. 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. 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.
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. Weaver makes the
Trail's End brand of popcorn sold by the
Boy Scouts of America. A
ConAgra spokesperson has said it'll do the same in a year, and is working to remove the ingredient from its popcorn products.
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."
EU regulation
The EU Commission has declared that diacetyl is legal for use as a flavouring substance in all EU states. 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. 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. 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 can't be excluded when inhaling diacetyl, EFSA will give priority to the re-evaluation of this substance and provide detailed scientific advice."
Further Information
Get more info on 'Diacetyl'.
|
External Link Exchanges
Do you know how hard it is to get a link from a large encyclopaedia? Well we're different and will prove it. To get a link from us just add the following HTML to your site on a relevant page:
<a href="http://diacetyl.totallyexplained.com">Diacetyl Totally Explained</a>
Then simply click through this link from your web page. Our crawlers will verify your link, extract the title of your web page and instantly add a link back to it. If you like you can remove the words Totally Explained and embed the link in article text.
As long as your link remains in place, we'll keep our link to you right here. Please play fair - our crawlers are watching. Your site must be closely related to this one's topic. Any kind of spamming, dubious practises or removing the link will result in your link from us being dropped and, potentially, your whole site being banned. |