It really all depends on your setting...
Stereotype-wise, I voted orc, because honestly, for some reason I would think an "evil" race would have more potent booze. Don't ask me to make that make sense. That said, in my WIP orcs aren't evil, and are actually rather smart and un-orc-like, by most standards. But I digress...
I would say Orc > Dwarf > Elf > Halfling > Human. Last two perhaps interchangeable. Orcs have the nastiness to want super-potency, and dwarfs and elfs would have the age/experience and possibly magic to have the know-how to make super-old, super-strong liquor. Humans and halflings, by contrast, don't really have anything in their favor...humans have inventiveness, and halflings have passion for the subject matter. Neither really compare to magic or experience, hence their place at the bottom of my mental list.