9.25.5 - Total sulphur dioxide in beer by DTNB method with quick test kits (IM)
- 29/06/2026
- 28
- |
- Beer
- |
- 2024
The purpose of this method is the determination of total sulphur dioxide in beer. Sulphites, like sulphur dioxide, are a group of sulphur-based substances which are produced naturally during fermentation and are also used as food additives for their preservative and antioxidant properties. This method describes the determination of Total Sulphur Dioxide in beer using DTNB method with quick test kits a) CDR BeerLab®, b) Merck Spectroquant, c) Megazyme K-TSULPH of Neogen. The method is based on the reaction between sulphur dioxide and 5,5’-dithiobis nitrobenzoic acid (DTNB) in basic conditions. The absorption is measured on a photometer of the supplier (CDR BeerLab®) or a spectrophotometer (Spectroquant or Megazyme test). The method has been validated to cover a total sulphur dioxide range of 1,0 to 19,4 mg/L. Basic laboratory skills, including pipetting skills, are sufficient to accomplish the semi-automated (CDR BeerLab®) or manual (Spectroquant/Megazyme) method successfully, the beer samples should be briefly degassed. Labour time and total analysis time are short; within 1 hour (CDR BeerLab®/Megazyme) the results can be reported of a few samples; for Spectroquant you need 1 to 2 hours. The reagents used do not present a specific risk, however you need to wear safety gloves and glasses when you work with reagent 1 (SO3-1) of Megazyme.
