First thought is to insulate the line. Thinking the 1/2" pipe insulation might work. Otherwise you'll need something like a tower cooling unit, except it'll be horizontal. If the 8" of line gets warm you have some foam on the first warm pour is about it. Cheers!!!
Edit: IP ya got me by a nose... :-)
If Homebrew & BBQ aren't the answer, then you're askin' the wrong questions... Cheers!!!