Please describe what you want on the screen with the portal in more detail. Such a portal implies a one to many relationship. Do you want the layout based on Beers with a portal to all inventory entries for that one Beer?
On another note, I suggest not using the name of the beer in your relationships. Use a serial number field instead. You never know, a brewery might change the name and even if they don't, data entry errors with the beer names can create problems when you try to fix the error after related records based on that incorrectly entered name have been created.