Small beer

Small beer is a beer that contains very little alcohol, perhaps less than one percent. Sometimes unfiltered and porridge-like, it was a favored drink in Medieval Europe and colonial North America. It was sometimes had with breakfast, as attested in Benjamin Franklin's autobiography. Before public sanitation?, water-transmitted diseases, such as cholera?, were a significant cause of death. Because alcohol is toxic to most water-borne pathogens, drinking small beer instead of water was one way to escape infection.

Metaphorically, small beer means a trifle, a think of little importance.