Tips for getting an accurate free sulfur dioxide reading on the Sentia™
Sentia User's must be mindful that free sulfur dioxide (FSO₂) is a highly volatile compound, sensitive to oxygen and oxygen binding events. This means that FSO₂ samples need to be collected with particular care and tested rapidly for best results.
Tips for FSO₂ sampling:
- Collect a homogenous sample
- Collect a decent sized sample; DO NOT transfer/apply miniscule or bubbled volumes to your Sentia device. Over aerated samples can lead to lower than true figures.
- Test FSO₂ samples IMMEDIATELY post-collection where possible.
- If you cannot test your FSO₂ sample immediately (or you're conducting a comparison with another FSO₂ method), store the sample in a sealed vessel containing little to no air until use.
- DO NOT test FSO₂ with the Sentia device (or any other device) immediately after making any SO₂/potassium metabisulfite additions to your wine. The wine will need at least 24 hours after a dosing event to settle and re-stabilize before testing. *
- DOT NOT test FSO₂ on highly carbonated samples.
Figure 1. Dos & don'ts for FSO₂ sample collection.
Figure 2. Dos & don'ts for FSO₂ sample storage.
* Note: when adding potassium metabisulfite (PMS) additions to wine, the change in free sulfur levels may not read as expected if the PMS used is old or degraded. Store PMS in a moisture/humid-free environment when not in use and check expiry dates.