Determination of free sulfur dioxide in wine
Sulfur dioxide (SO2) is used in oenology mainly as preservative, but also for other purposes (for example for antiseptic, antioxidant, antioxidasic, solubilizing, combining and clarifying functions). Part of the SO2 that is added as potassium metabisulfite to musts and wines undergoes a series of reactions. Therefore, after a short period of time, most of the sulfur dioxide reacts with some of the substances present, binds with them and forms addition compounds (combined sulfur dioxide) that are unable to express the typical properties of unbound molecules. Therefore, only the part that does not combine (free sulfur dioxide) plays an important role in preserving wine from oxidizing alterations and from some micro-organisms. This test can be used to determine the fraction of free SO2.
The Analyzers CDR WineLab® for determining Free sulfur dioxide in Wine and Must
The system is supplied pre-calibrated and ready for use.
Results are expressed in accordance with the reference method.
It is also possible to standardize the system using samples with a known titration.
The reagents have a shelf-life untill 18 months
The analytical methods are simple: the system does not require an equipped laboratory or skilled staff.
|CDR WINELAB®||CDR WINELAB® JUNIOR|
Free sulfur dioxide (Free SO2)
Total sulfur dioxide (Total SO2)
Yeast assimilable nitrogen (YAN)
TPI – Total Polyphenols Index
Colour intensity and tonality
|Configuration with tailored panel of analyses|
|Simultaneous Sample Analyses||16||3|
|Multiple Analyses on a Sample||–|
Test type: kinetic.
Testing time: one test 3 minutes – 60 Tests/hour.
Are possible test sessions with several samples, up to a maximum of 16.
The calibration curve of CDR WineLab®, obtained using reference methods.
SO32- + RSSR <—–> RSSO3– + RS-.
The free fraction of sulfur dioxide is made to react with an organic disulphide in order to form a colored compound, whose intensity, measured at 420 nm in kinetics, is directly proportional to the concentration of free sulfur dioxide in the sample.
Reagent test Kits
The reagents are packaged in foil pouches containing 10 tubes useful to perform 10 analyses.
This is the minimum package that allows the use of CDR systems even to those who need to make a few analyses, thus not wasting reagents.
There are also boxes of 100 tests, however, packaged in 10 bags of 10 tubes containing the reagent.
Code. 300345 : 10 tests
Code. 300333 : 100 tests (10 packages of 10 tests)
The reagents have a shelf-life of 18 months
Processing – Sample Volume – Measuring Range direction
Use the wine as is.
|Free SO2||1 – 60||25 µL||1||1,5 mg/L|