Conversation so far:
other than taste and texture how is guinness beer different from other beers
Guinness contains the most folate of the imported beers, one of the highest levels of fiber, a lower alcohol content, and is lower in calories compared with other beers.
what is guinness stout made of
Guinness stout is made from water, barley, roast malt extract, hops, and brewer's yeast.

Question: what makes the beer dark
Self-contained rewrite: what makes guinness stout dark