Even if it does not exactly replicate the beer that Pharaoh, King David or Jesus drank in ancient times, the unique brew sampled by a group of lucky reporters in Jerusalem today contains yeast colonized from Philistine-era vessels at least 3,000 years old.
The golden beer resulted from painstaking detective and scientific work done by a multidisciplinary group of researchers from Hebrew University, Tel Aviv University, Bar-Ilan University and Ariel University, and the Dead Sea Arava Science Center, along with Israeli beer expert Itai Gutman and certified tasters from the International Beer Judge Certification Program under the direction of brewer Shmuel Nakai, owner of Biratenu beer emporium in Jerusalem.
“Reconstruction of ancient beer so far had been done using ancient recipes and modern ingredients. But one of the most important ingredients in beer is the yeast, and everybody who reconstructs beer uses modern yeast like you buy in the supermarket and for sure it’s not the same,” said Hebrew University microbiologist Ronen Hazan, who spearheaded the project with colleague Michael Klutstein.
First, the two researchers devised a method for isolating yeast from the porous walls of broken clay vessels they got from Israel’s Kadma Winery, reportedly the only winery in the world that uses clay vessels for production.
In 2015, remains of an ancient Egyptian brewery had been found in Tel Aviv. Hazan and Klutstein asked the Israel Antiquities Authority if they could try to isolate yeast from the vessels found there.
The IAA gave them 21 jugs as old as 5,000 years, from the Tel Aviv site and other sites, from which they successfully isolated and authenticated six yeast strains and made various beers. These experiments are described in a scientific paper published in mBio by the research team.
The yeast used in the beer revealed today in Jerusalem originated from colonies in Iron-Age Philistine jugs given to them by Prof. Aren Maeir of Bar-Ilan University, lead archeologist on the Tel es-Safi/Gath Archaeological Project halfway between Jerusalem and Ashkelon.
“Beer was an important beverage for the Philistines for its high caloric content and because it was safer to drink than plain water,” explained Maeir.
“It’s not that the yeast in this beer is the original yeast from thousands of years ago but we think the yeast colony was growing for [thousands of years] inside the pores of the vessel, and we were able to salvage all the living organisms in the vessels’ nanopores, revive them and study their properties,” explained Klutstein.
“We now have a new tool in archeobiology to study the traits of something ancient. Just like bacteria can survive for thousands of years, yeast can actually survive a long, long time without food.”
Professors Yuval Gadot and Oded Lipschits from Tel Aviv University contributed restored pottery jugs to the research that were found at Ramat Rachel on the southern edge of Jerusalem, stamped “Judea.” These jugs date from approximately 500 BCE.
“We were excited when we learned there was an option to check their content. The result was they held not beer but mead, a fermented honey drink, meaning there was a beekeeping industry in ancient Judea,” said Gadot.
In the ancient world, people of every age, gender and social class drank beer as their main beverage from infancy, said Yitzchak Paz of the Israel Antiquities Authority. “Every ancient Egyptian soldier drank about 3 liters of beer daily.”
So how does the new-old beer taste? Pretty much like any standard beer on the market today.
“This is not really the authentic taste but it’s much closer than anything done before. We are planning to find out which plants were used and try to get closer to the ancient beer,” said Hazan. “This one was made from a standard beer recipe using the Philistine yeast found in vessels in Tel es-Safi. It’s a descendant of the ancient yeast.”
“We are talking about a real breakthrough here,” said Paz. “This is the first time we succeeded in producing alcohol from the original substances.”