A small Brussels-based brewery has embarked on a project to make beer from leftover bread, harking back to antiquity, when bread, rather than barley, was the main ingredient.

The idea for brewing with bread came when 31-year-old Frenchman Sebastien Morvan talked to a friend about food waste, specifically the bread thrown away be­cause supermarkets, eager to offer fresh bread to shoppers all day, baked until late afternoon.

“Twelve per cent of food waste in Brussels is bread – it’s quite astonishing,” Morvan, one of the founders of microbrewery Brussels Beer Project, said.

Morvan calculated that about 30 per cent of the barley used in brewing could be replaced with one-and-a-half slices of bread per bottle. Brewing 4,000 litres would use up 500 kilos of bread. A nearby social project, Atelier Groot Eiland, arranged to get unsold bread from nearby supermarkets, dry it and cut it into flakes for him.

The oldest surviving recipe for beer dates back about 4,000 years

The oldest surviving recipe for beer dates back about 4,000 years to ancient Mesopotamia and calls for thick, multigrain loaves to be mixed with honey. The Belgian bread beer is more modern, using hops from the US and Britain and adds yeast instead of relying on spontaneous fermentation.

Getting the recipe right took about a year. Initial trials failed before the brewers worked out the ideal ratio of bread to barley and how to cut the bread so it would not clog the brewing equipment.

Sebastien Morvan is one of the founders of microbrewery Brussels Beer Project. Photos: Yves Herman/Reuters

The resulting beer, called Babylone, is a seven per cent amber brew, with a subtly salty taste from the bread and a hoppy finish. For now, most of it is being sold to local cafes and bars.

“It’s fusion between maybe what they used to do with bread 1,000 years ago and contemporary brewing,” said Morvan. “It might not please everybody’s palate, but I think the ones who like this will really enjoy it.”