Originally Posted by fun4stuff
thanks. BTW- as a follow-up to above posts: sulfite taste was gone today.
I've found that there is often that "sulphite whiff" when it's been recently added.
You hit the nail on the head how the sulphites work i.e. the metabisulphite is added and dissolved, and the acids in the wine/mead/etc then break it down to provide free SO2.
This does dissipate over time, or if you needed to stir the mix it dissipates quicker. Yet there's normally still enough free SO2 to keep any fungal nasties that might be floating around, in check......
The warning that you see on wine bottles is to do with people with asthma, as the presence of sulphites can, on rare occasions, trigger an attack.
If you encounter people or someone who does suffer with that, you find that you end up making batches that are staggered nutrient and step fed, so that you always reach or surpass the tolerance of the yeast, so that you don't need to use sulphites or stabilisers to prevent refermentation and you can just use fermentable sugars to back sweeten etc, because it can't restart. Plus there's enough alcohol content to act as the preservative.
You just end up doing the clearing etc.....