How to ensure accurate free sulfur dioxide results

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 (as outlined in How to take a wine 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/PMS 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.