Yep - probably gone by the time we finished mixing it - and I doubt there is a test that can be done to detect amounts that small.
The good news is that a lot of the flavour companies we use are slowly but surely changing their flavour creations to use chemicals that do not need alcohol as a solvent, and as they come out, we replace them and update the site accordingly.
Same goes for acetoin, they are replacing it with Butyric Acid - it is naturally occurring in milk, butters, and some cheeses and gives the same buttery, custard notes as acetoin.
