For years we’ve used Laffort Oenosteryl effervescent SO2. It is fast, convenient, and the effervescence helps distribute the SO2. However the expiration dates are very conservative (expire fast), and I often have unused boxes beyond expiry.
Has anyone tested expired Oenosteryl? I know how (make a stock dilution and test with my Vinmetrica titration setup), but it is a hassle and I was hoping someone already did this.
I’ve never used Oenosteryl but I don’t see any reason why unopened product wouldn’t last effectively indefinitely. My only issue with old effervescent SO2 has been that it clumps and so becomes a pain to use. But I have used pure KMBS that is >5 years old with no problem.
