Determination of Total Sulfur Dioxide in Cider
With CDR CiderLab is possible to determine the Total Sulfur Dioxide (SO₂) in cider in 1 minute with a simple photometric reading using the cider as is without having to resort to the distillation according with the reference method or to the iodometric titration according with the simplified method. Calibration is not necessary.
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 juice and ciders 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 cider from oxidizing alterations and from some micro-organisms.
This test can be used to determine the total content of SO2 in cider, which is the sum of the free and combined sulfur dioxide fractions.
Method
Sample treatment
If necessary, the sample shall be degassed using the specific ultrasonic bath (code 222062). In case of tests performed on must, the sample shall be centrifuged (code 222061) or filtered (code 300210).
Principle of the test
The total sulfur dioxide contained in a cider or must is made to reacts 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.
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Calibration curve
The calibration curve of CDR CiderLab, obtained using reference methods, confirms the excellent linearity of the system over the whole testing range.
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Reagent test Kits
Code*300350: 10 tests
Measuring range
| Analyses | Measuring range | Resolution | Repeatability |
|---|---|---|---|
| Total SO2 | 15 - 250 mg/L | 1 mg/L | 4 mg/L |
The Analyzers for process and quality control in cider production
CDR CiderLab
Complete analysis panel, supplied already configured
Up to 16 determinations simultaneously
Possibility of carrying out analyses of the same sample
Integrated printer
Full connections (LAN - USB - Bluetooth barcode/QR code reader)
CDR CiderLab Jr
Partial analysis panel, customisable configuration
Up to 3 determinations simultaneously
Wireless connection to external printer
USB connections