Researchers say they have found the world’s oldest brewery, with residue of 13,000-year-old beer, in a prehistoric cave near Haifa in Israel.The discovery was made while they were studying a burial site for semi-nomadic hunter-gatherers.Brewing beer was thought to go back 5,000 years, but the latest discovery may turn beer history on its head.The findings also suggest beer was not necessarily a side product of making bread as previously thought.he ancient brew, which was more porridge or gruel-like, is thought to have looked quite unlike what we know as beer today.The research team has managed to recreate the ancient brew to compare it with the residue they found.This involved first germinating the grain to produce malt, then heating the mash and fermenting it with wild yeast, the study said.The ancient booze was fermented but probably weaker than modern beer.