Hmm. It'd have to be an additive that's present in both beer and port. Any idea where I can find a tame biochemist (preferably with special knowledge of booze :-) to answer questions like that?

Gah, I'm using lynx in putty and I can't make it copy and paste. Hope I copy it right:

www.ukparents.co.uk/archives/az_food_allergy.shtml

says that beer has got sulphites in as well as wine. But I've got no idea how many other zillions of preservatives or what other things it *might* have in it and which *might* make you ill etc, just that that is known as a "standard" asthma trigger, which is why they warn you against it. Remind me later and I'll dig out my books on additives.

And all the biochemists I know are a pretty wild bunch ;-)