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
This method describes how to evaluate the sensory properties of filter aids and stabilization agents.
Filter aids and stabilization agents which are used in the brewing and food production industries
This test provides information regarding any odors transferred by filter aids to wort and beer. A minimum of three samples should be collected from each lot of the product delivered.
This method describes how to test the sensory impact of filter aids and stabilizing agents under normal operating conditions.
Filter aids and stabilizing agents which are used in the brewing and food production industries
In order to test the influence and effects of filter aids in a routine production situation, it is recommended that a filtration trial be conducted under standard operating conditions.
The odor and flavor of the filtered beer is also tested as part of this trial.
The test should be conducted against a control sample that has not been in contact with the material to be tested.
This method describes how to evaluate the sensory impact of lactic acid or food-grade lactic acid.
Lactic acid or food-grade lactic acid which are used in the brewing and food production industries
Food-grade lactic acid may be used to adjust the pH during mashing and wort production for products not subject to the regulations of the Reinheitsgebot or the German purity law concerning beer.
The method describes how to determine pesticides and biocidal products in drinking water using high performance liquid chromatography.
Water intended for use as an ingredient in the production of beer (brewing liquor) or other foods
The determination is carried out by means of HPLC (refer to W-010.06.120 Quantitative Determination of Polycyclic Aromatic Hydrocarbons (PAH) in Drinking Water).
This method describes how to determine the chemical oxygen demand in wastewater through oxidation with potassium dichromate.
Potassium dichromate is added to the acidified sample as an oxidizing agent along with silver sulfate as a catalyst; mercury sulfate is also added to prevent the formation of elemental chlorine from chlorides. After oxidation of the organic substances in the sample (the dichromate ion is reduced to the chromium(III) ion in an acidic solution), the chromate required to achieve this is determined through reverse titration of the excess potassium dichromate with iron(II) solution (adjusted) against ferroin as an indicator [1].
Cr2O72- + 6 e- + 14 H3O+ → 2 Cr3+ + 21 H2O
Cr2O72- + 6 Fe2+ + 14 H3O+ → 2 Cr3+ + 6 Fe3+ + 21 H2O