The INCI for beer is Beer so you don't have to list all the ingredients within it. I am a total soap labeling geek and I do list everything via the INCI including all essential oils. The reason I do this is because allergies are a very real consideration these days and INCI was developed so a dermatologist or even your family doctor can look up the ingredient and know exactly what it is. For instance if you google Sodium Olivate you come up with
In my experience most brewers are happy to have the free advertising of having their name appear on your label and permission is super easy to obtain. For me I have a local craft brewer that I'm working with has allowed me to name 2 products after the brew that I'm using (PowTown Porter). It makes for great interest in your soaps as well as your company.
Now the flying pig....
I freaken love it!!!!!! That is all I have to say on that subject....