Dimethyl dicarbonate
Encyclopedia
Dimethyl dicarbonate or DMDC is a colourless liquid with a sharp odour. Its primary use is as a beverage
preservative
and or processing aid or sterilant (INS No. 242), and acts by inhibiting
the enzyme
s acetate kinase
and L-glutamic acid decarboxylase. It has also been proposed that methoxycarbonylation of the histidine
part of the enzymes alcohol dehydrogenase
and glyceraldehyde 3-phosphate dehydrogenase
by DMDC inhibits these essential enzymes also. Once it has been added to beverages, the efficacy of the chemical is provided by the following reactions:
DMDC is sometimes used as a preservative in wine
as a replacement to sulfur dioxide
, inactivating wine spoilage yeasts such as Brettanomyces
. In the U.S. the FDA
approved its use in wines in 1988, with the maximum permitted level being set at 200 mg/L, and only if there were fewer than 500 yeast cells/mL at time of dosage. It is listed as approved in the EU (where it is listed under E number
E242) and USA but is not listed in Australia and New Zealand. The application of DMDC is particularly useful when wine needs to be sterilised but cannot be sterile filtered, pasteurized
, or sulfured.
DMDC is used to stabilise non alcoholic beverages such as carbonated or non carbonated juice beverages, isotonic sports beverages, iced teas and flavoured waters.
DMDC is added before the filling of the beverage. It then breaks down into small amounts of methanol
and carbon dioxide
, which are both natural constituents of fruit and vegetable juices.
The EU Scientific Committee on food, the FDA in the United States and the JECFA of the WHO have confirmed the safe use in beverages.
Drink
A drink, or beverage, is a liquid which is specifically prepared for human consumption. In addition to fulfilling a basic human need, beverages form part of the culture of human society.-Water:...
preservative
Preservative
A preservative is a naturally occurring or synthetically produced substance that is added to products such as foods, pharmaceuticals, paints, biological samples, wood, etc. to prevent decomposition by microbial growth or by undesirable chemical changes....
and or processing aid or sterilant (INS No. 242), and acts by inhibiting
Enzyme inhibitor
An enzyme inhibitor is a molecule that binds to enzymes and decreases their activity. Since blocking an enzyme's activity can kill a pathogen or correct a metabolic imbalance, many drugs are enzyme inhibitors. They are also used as herbicides and pesticides...
the enzyme
Enzyme
Enzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates...
s acetate kinase
Acetate kinase
In molecular biology, acetate kinase , which is predominantly found in micro-organisms, facilitates the production of acetyl-CoA by phosphorylating acetate in the presence of ATP and a divalent cation. The enzyme is important in the process of glycolysis, enzyme levels being increased in the...
and L-glutamic acid decarboxylase. It has also been proposed that methoxycarbonylation of the histidine
Histidine
Histidine Histidine, an essential amino acid, has a positively charged imidazole functional group. It is one of the 22 proteinogenic amino acids. Its codons are CAU and CAC. Histidine was first isolated by German physician Albrecht Kossel in 1896. Histidine is an essential amino acid in humans...
part of the enzymes alcohol dehydrogenase
Alcohol dehydrogenase
Alcohol dehydrogenases are a group of dehydrogenase enzymes that occur in many organisms and facilitate the interconversion between alcohols and aldehydes or ketones with the reduction of nicotinamide adenine dinucleotide...
and glyceraldehyde 3-phosphate dehydrogenase
Glyceraldehyde 3-phosphate dehydrogenase
Glyceraldehyde 3-phosphate dehydrogenase is an enzyme of ~37kDa that catalyzes the sixth step of glycolysis and thus serves to break down glucose for energy and carbon molecules...
by DMDC inhibits these essential enzymes also. Once it has been added to beverages, the efficacy of the chemical is provided by the following reactions:
- DMDC + H2O → 2CH3OH + 2CO2
- DMDC + EtOH → Ethyl methyl carbonate
- DMDC + NH3 → Methyl carbamate
- DMDC + Amino acidAmino acidAmino acids are molecules containing an amine group, a carboxylic acid group and a side-chain that varies between different amino acids. The key elements of an amino acid are carbon, hydrogen, oxygen, and nitrogen...
→ Derived carboxymethyl
DMDC is sometimes used as a preservative in wine
Wine
Wine is an alcoholic beverage, made of fermented fruit juice, usually from grapes. The natural chemical balance of grapes lets them ferment without the addition of sugars, acids, enzymes, or other nutrients. Grape wine is produced by fermenting crushed grapes using various types of yeast. Yeast...
as a replacement to sulfur dioxide
Sulfur dioxide
Sulfur dioxide is the chemical compound with the formula . It is released by volcanoes and in various industrial processes. Since coal and petroleum often contain sulfur compounds, their combustion generates sulfur dioxide unless the sulfur compounds are removed before burning the fuel...
, inactivating wine spoilage yeasts such as Brettanomyces
Brettanomyces
Brettanomyces is a non-spore forming genus of yeast in the family Saccharomycetaceae, and is often colloquially referred to as "Brett". The genus name Dekkera is used interchangeably with Brettanomyces, as it describes the teleomorph or spore forming form of the yeast. The cellular morphology of...
. In the U.S. the FDA
Food and Drug Administration
The Food and Drug Administration is an agency of the United States Department of Health and Human Services, one of the United States federal executive departments...
approved its use in wines in 1988, with the maximum permitted level being set at 200 mg/L, and only if there were fewer than 500 yeast cells/mL at time of dosage. It is listed as approved in the EU (where it is listed under E number
E number
E numbers are number codes for food additives that have been assessed for use within the European Union . They are commonly found on food labels throughout the European Union. Safety assessment and approval are the responsibility of the European Food Safety Authority...
E242) and USA but is not listed in Australia and New Zealand. The application of DMDC is particularly useful when wine needs to be sterilised but cannot be sterile filtered, pasteurized
Pasteurization
Pasteurization is a process of heating a food, usually liquid, to a specific temperature for a definite length of time, and then cooling it immediately. This process slows microbial growth in food...
, or sulfured.
DMDC is used to stabilise non alcoholic beverages such as carbonated or non carbonated juice beverages, isotonic sports beverages, iced teas and flavoured waters.
DMDC is added before the filling of the beverage. It then breaks down into small amounts of methanol
Methanol
Methanol, also known as methyl alcohol, wood alcohol, wood naphtha or wood spirits, is a chemical with the formula CH3OH . It is the simplest alcohol, and is a light, volatile, colorless, flammable liquid with a distinctive odor very similar to, but slightly sweeter than, ethanol...
and carbon dioxide
Carbon dioxide
Carbon dioxide is a naturally occurring chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom...
, which are both natural constituents of fruit and vegetable juices.
The EU Scientific Committee on food, the FDA in the United States and the JECFA of the WHO have confirmed the safe use in beverages.