Alright, a short question from me. What kind of Skill could be use in identifying if a wine is of a famous brand or not?

Trade (Cook), I'd think.

Perhaps a Hard Carouse test. 

It could even be a Chem-use test, but I suppose you'd need some sort of tool-kit or laboratory for that.

Definitely Chem-use/tech-use with appropriate instrumentation IMO.  Though I would probably allow someone with an appropriate knowledge (e.g. CL: fine wines…) to determine it by taste.

Well, if you're going with the science-approach, Chem Use is not the skill to use.

Chem Use is for administering drugs, basically using chems without suffering ODs or other complications. To identify or cook up stuff, you need either Scholastic Lore Chymistry or a related Trade(skill).

If you're thinking more of a connoisseur who knows his wines, then  Carouse or a relevant Trade skill (like Cook)

Says in the book under Chem-use that it can be used to identify various chemicals.

SL: Chymistry is knowledge of chemicals and would surely help but as Primateus says the primary skill here would be chem-use to do some work identifying the characteristic compounds present.  Your average chemist is generally good at synthesising chemicals but the methods available for determining identities in a complex mixture are very specialised, not to mention the fact that a specific complex mixture would be very hard to confirm unless there is a very characteristic ingredient.

Having said that the equipment required to do this is also going to be very rare in any DH world.  It is rare enough irl (I am in an analytical group at a university).  I would have thought that there might be other less scientific ways to trace the origin of the bottle.

Chem Use or Lore: Chymistry could be used to determine a wine's alchohol content and whatnot, but not that a Quaddis Noirberry '712 is a highly prized vintage. Hmm… I don't have the rulebooks handy, but I seem to recall that the Noble Born background from Inquisitor's Handbook starts with some kind of Etiquette skill…?

I think we are talking about identifying

"whether that bottle over there is Quaddis Noirberry '712"

rather than

"whether that bottle over there is a good wine"

Actually, the best skill in my mind: Evaluate: "A successful check reveals the market value of the object plus perhaps some additional infomation about the object." There you have it.

Thanks alot guys. :) Its the situation where a noble wants to check out what wine he's drinking and so I will go with Carouse -20 to identify the vintage.