In some recent scholarship it has been suggested that ancient Greeks commonly drank beer. However, a careful examination of ancient sources, both for negative evidence (the lack of references to beer-making and beer-drinking among Greeks) as well as for positive evidence (the mentions of beer as a foreign product), supports the commonly held belief that Greeks in the archaic and classical periods did not regularly drink beer. There is also no evidence that kykeon was a type of beer.
Nelson, Max. (2014). Did Ancient Greeks Drink Beer?. Phoenix, 68 (1/2), 27-46.