(CN) — A newly discovered method for detecting the presence of beer in archaeological findings could help unlock the mysteries of how prehistoric cultures brewed malted beverages, performed rituals and organized their societies.
“There are so many ritual behaviors in our societies that make up a lot of our everyday life,” said Andreas Heiss, an archaeobotanist at the Austrian Archaeological Institute at the Austrian Academy of Sciences. “Finding specific components of everyday food and ritual food is very useful in finding out how societies work.”
Heiss and a team of researchers set out to solve a puzzle: how charred remnants of cereal grains from archaeological sites in central Europe were used by humans. By analyzing the relics under a high-powered microscope, the researchers found unusually thin cell walls in the outer layers of endosperms. Endosperms, the central part of grain kernels packed with starch, are essential components for bread- and beer-making.
“We found weird structures and wanted to know what they were,” Heiss said.
One theory emerged: that the shrinking cell walls resulted from beer brewing or malt-based food production. To test their theory, the researchers artificially charred malted barley and compared the simulated grains to charred grains from five archaeological sites dating back to at least 3000 B.C. The charred grains came from two known beer-brewing sites in Egypt and three central European lakeshore settlements where cereal-based foods were found in containers, but the presence of beer was not confirmed.
The same effect observed in the experimental grains was found to be “much more pronounced” in the archaeological grains. Thin cell walls on the outer layer of endosperms were identified as a hallmark of beer brewing or malt-based food production.
“The real excitement about this is it’s not just a small study on a small site, but the discovery of something that is really useful for the whole field of archaeology,” Heiss said.
The new method for detecting ancient beer was revealed in a study published in the journal PLOS ONE Wednesday.
The history of beer goes back at least 5,000 years in ancient China, where archaeologists found beer-brewing equipment in underground rooms built between 3400 and 2900 B.C.
In the West, the oldest evidence of beer brewing has been traced to ancient Egypt and Mesopotamia, including at the Godin Tepe settlement located in modern-day Iran between 3500 and 3100 B.C. and possibly at the Gobekli Tepe settlement in what is now southeastern Turkey.
Finding beer recipes from ancient civilizations is extremely rare. If one were to taste an ancient beer, Heiss says it would almost certainly taste more like a modern sour beer than a modern lager.
“The reason for this is that a ‘natural’ mixture of microorganisms almost always contains not just yeasts, but also lactic acid bacteria,” Heiss said.
Beer and other alcoholic beverages continue to play complex roles in human societies, promoting social bonding, rituals and the formation of social elites. Large quantities of malted barley were found in some ancient European sites where large feasts were held by local rulers as “an instrument of showing off power and forging alliances,” Heiss explained.
In the past, archaeologists used various methods to uncover traces of beer and alcoholic beverages, such as finding evidence of brewing equipment and drinking vessels. But proving the presence of beer from grain remnants has posed challenges. Traditional indications of brewing such as carbon dioxide produced in the fermentation process have little chance of remaining detectable after thousands of years.
Cereal grains and other foods that become charred in a baking, brewing or cooking accident or fire are chemically altered and can stay in the soil without decomposing or changing over time.
“Thus, charred remains can survive centuries or millennia in the ground, more or less unchanged,” Heiss explained.
Prior to this discovery, identifying malt in archaeological remains relied on intact grains. With this new method, Heiss says, “even a speck of dust” from cereal grain in a piece of charred crust can be used to identify the presence of malt.
Using this new technique, Heiss and his team were able to identify the oldest traces of malt-based food in Neolithic Europe, the period ranging from 6500 BC to 3500 B.C.
“We cannot claim for sure that we also identified the oldest beer traces of central Europe — but we are quite confident,” Heiss said.
This new diagnostic tool could help archaeologists discover what other ancient civilizations brewed alcohol and how common beer brewing was in the ancient world.
It could also spur other questions for future research on ancient beer-brewing civilizations. Was beer brewing an activity only performed by men or women in certain cultures? Did one person brew beer for an entire community, or did each family brew their own beer? Did ancient civilizations have their own “microbreweries?”
These are some of the questions Heiss is excited to explore.
“Our research has but unlocked a door,” Heiss said.