If in any doubt it is always best to contact the airline or travel agent to ask before arriving at the airport only to be charged for excess baggae.
I tend to find that if you aren't taking your own ski equipment then 20kg for a week is more than achievable.
As a whisky drinker, I must confess to preferring whisky to beer myself. Just be careful to pad it well before packing it as you wouldn't want to open your bag only to see all that lovely whisky wasted dur to breakage. I usually cry when that happens!