I'd be curious to know if any poison - that one can readily buy in a shop - is potent enough to be harmful if 1 drop is diluted into 20L of wort that is then boiled for an hour.I'd always been put off by the "POISON" printed on bottles of metho
and since using for yeast cuturing would end up in the beer we drink
- or would the amount ending up in the beer be so low as to be
negligible?
(Botulin toxin is one of the most powerful known toxins: about one microgram is lethal to humans, but the botulinum toxin is destroyed by thorough cooking over the course of a few minutes).
Besides as manticle said the metho is burned away in the flaming process.