April 19 (UPI) -- The study of an ancient microbrewery in Peru and its supply of a sour beer has provided scientists new insights into the stability of the Wari empire.
For several years, researchers have been studying the remains of a brewing site at Cerro Baúl, an ancient city in southern Peru and the political center of the Wari empire, which lasted from 600 to 1100 AD -- a long time for an ancient dynasty.
According to archaeologists, the brewing site played an important role in the development the empire's political organization.
"It was like a microbrewery in some respects. It was a production house, but the brewhouses and taverns would have been right next door," Ryan Williams, an associate curator and head of anthropology at the Field Museum in Chicago, said in a news release.
Williams and his colleagues estimate political elites regularly gathered at the brewery to drink a locally made sour ale called chicha.
"[Chicha] was only good for about a week after being made, it wasn't shipped offsite -- people had to come to festivals at Cerro Baúl to drink it," Williams said. "These festivals were important to Wari society."
For the latest study, researchers blasted the insides of one of the beer-drinking vessels with a laser. The laser helped separate a layer of the beverage from the ceramic. When researchers heated the ancient beer molecules, they were able to discern some of the ingredients.
Scientists determined the sour ale was made using pepper berries, a drought resistant plant. They also confirmed the ceramic drinking vessels were locally made. The findings -- published this week in the journal Sustainability -- suggests the Wari's beer supply was immune to unfavorable weather and trading disruptions.
Even when instabilities arose, the Wari empire always had beer. Researchers at the Field Museum suggest the beverage was a tool of political unity.
"We think these institutions of brewing and then serving the beer really formed a unity among these populations, it kept people together," said Williams.