Determination of Total Sulfur Dioxide in wine
With WineLab is possible to determine the Total Sulfur Dioxide in wine in 1 minute with a simple photometric reading using the wine as is without having to resort to the distillation according with the reference method OIV or to the iodometric titration according with the simplified method. Calibration is not necessary.
The Analyzers CDR WineLab® for determining Total 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 | |
|---|---|---|
| Analyses | Fermentable Sugars Total Acidity Acetic Acid L-Lactic Acid L-Malic Acid Malolactic Fermentation Alcohol Free sulfur dioxide (Free SO2) Total sulfur dioxide (Total SO2) pH Yeast assimilable nitrogen (YAN) Gluconic Acid Glycerol Polyphenols TPI – Total Polyphenols Index Acetaldehyde (Ethanal) Anthocyanins Catechins Colour intensity and tonality Copper | Configuration with tailored panel of analyses |
| Simultaneous Sample Analyses | 16 | 3 |
| Multiple Analyses on a Sample |  | – |
Method
Test type: End Point.
Time testing: one test 1 minute – 80 Test/Hour.
Are possible test sessions with several samples, up to a maximum of 16.
Calibration curve
The calibration curve of CDR WineLab®, obtained using reference methods.
Test Principle
SO32- + RSSR <—–> RSSO3– + RS-.
The sulfur dioxide contained in a wine is made to react with an organic disulphide in order to form a colored compound, whose intensity, measured at 420 nm in end-point, is directly proportional to the concentration of total sulfur dioxide in the sample.
Definition and scope of the test
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 total content of SO2 in wine, which is the sum of the free and combined sulfur dioxide fractions.
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. *300350: 10 tests
Code. *300334: 100 tests (10 packages of 10 tests)
The reagents have a shelf-life of 18 months.
Processing – Sample Volume – Measuring Range
Wine: use as is.
| Test | Measuring range (mg/L SO2) | Sample volume | Resolution | Repeatability |
|---|---|---|---|---|
| Total SO2 White Wine | 15 – 250 | 25 µL | 1 | 2,5 mg/L |
For samples with SO2 > 200 mg/L, use 10 µL of sample and multiply the result by 2.5.
