Determination of the correct Velcorin® dosage
flavored beverages, liquid tea concentrate, fruit wine, non-alcoholic wine
DMDC (Velcorin®) is used for the cold sterilization of non-alcoholic beverages. It essentially kills yeasts, bacteria and molds, with little effect on mold spores or yeast ascospores. Certain species of Lactobacillus possess an elevated resistance to Velcorin®.
There should be fewer than 500 microbes/cm3 at the time the dosage is added.
According to the EU guideline EG 1129/2011 [1], up to 250 mg/l DMDC may be added to flavored non-alcoholic beverages, non-alcoholic wine and liquid tea concentrates.
Dimethyl dicarbonate (Velcorin®) quickly dissociates in aqueous solutions almost completely to carbon dioxide and methanol. In addition, small amounts of ethyl methyl carbonate are formed through the reaction of DMDC with ethanol, which can be detected through GC-MS analysis techniques [2]. The amount of DMDC added to a beverage can be determined by measuring the content of EMC and ethanol. The Velcorin® dosage can be checked by measuring the amount of methanol quantitatively using GC analysis; however, the initial amount of methanol present in the product prior to adding Velcorin® must be determined.
H2O + C4H6O5 (DMDC) → 2CH3OH + CO2
250 mg Velcorin → 119.5 mg methanol + 164.1 mg carbon dioxide
C2H5OH + C4H6O5 (DMDC) → C4H8O3 + CH3OH+ CO2