methoxycarbonyl methyl carbonate
DMDC; Dicarbonic acid dimethyl ester; Dimethyl pyrocarbonate; Velcorin
3D model (JSmol)
|E number||E242 (preservatives)|
CompTox Dashboard (EPA)
|Molar mass||134.087 g·mol−1|
|Melting point||16 to 18 °C (61 to 64 °F; 289 to 291 K)|
|Boiling point||172 °C (342 °F; 445 K)|
|Viscosity||2.1 Pa·s (20 °C)|
|R-phrases (outdated)||R22 R23 R34|
|S-phrases (outdated)||S7/9 S26 S36/37/39 S45|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
|what is ?)(|
Dimethyl dicarbonate (DMDC) is an organic compound which is a colorless liquid with a pungent odor at high concentration at room temperature. It is primarily used as a beverage preservative, processing aid, or sterilant (INS No. 242), and acts by inhibiting the enzymes acetate kinase and L-glutamic acid decarboxylase. It has also been proposed that DMDC inhibits the enzymes alcohol dehydrogenase and glyceraldehyde 3-phosphate dehydrogenase by causing the methoxycarbonylation of their histidine components.
Use in wine
In wine, it is often used to replace potassium sorbate, as it inactivates wine spoilage yeasts such as Brettanomyces. Once it has been added to beverages, the efficacy of the chemical is provided by the following reactions:
- DMDC + water → methanol + carbon dioxide
- DMDC + ethanol → ethyl methyl carbonate
- DMDC + ammonia → methyl carbamate
- DMDC + amino acid → derived carboxymethyl
The application of DMDC is particularly useful when wine needs to be sterilized but cannot be sterile filtered, pasteurized, or sulfured. DMDC is also used to stabilize non-alcoholic beverages such as carbonated or non-carbonated juice beverages, isotonic sports beverages, iced teas and flavored waters.
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. The FDA approved its use in wines in 1988, with the maximum level being permitted set at 200 mg/L, and only if there were fewer than 500 yeast cells/mL at time of dosage. It is also approved in the EU, where it is listed under E number E242, as well as Australia and New Zealand.
- [dead link]
- DMDC's role in bottle stability - dimethyl dicarbonate, Wines & Vines, Oct 1990
- US Food and Drug Administration: "Listing of Food Additives Status Part I". Archived from the original on 2013-03-14. Retrieved 2011-10-27.
- UK Food Standards Agency: "Current EU approved additives and their E Numbers". Retrieved 2011-10-27.
- Food Standards Australia and New Zealand, Application A1015 - Classification of Dimethyl Dicarbonate - Approval Report -15 December 2010"Application A1025 - Classification of Dimethyl Dicarbonate". Retrieved 2010-12-15.