A new study has found that residents of Teotihuacan in ancient Mexico brewed a tequila-like drink called 'pulque' as a source of food and nutrition. Teotihuacan was the biggest city in the Americas before the arrival of Christopher Columbus.

According to a new study published in Proceedings of the National Academy of Science, 'pulque' is milky-white liquor made from the maguey plant, a relative of the agave used in tequila, and is still famous among the local residents. Traces of 'pulque' have been found on pottery shards dating at Teotihuacan dating back to 150 B. C.

Majority of the population used to have the beverage and it could have helped them to praise the diet of the people, said Marisol Correa-Ascencio, a doctoral student in chemistry at the University of Bristol (UK).

Researchers used a new approach to find out chemical remnants on the pottery. They use a lipid biomarker, or a tiny fat molecule bonded with the ceramic molecules of the vase-like amphoras that held the pulque and were sealed with pine resin.

"The principle is that when you process food like cooking or storing, the lipids are absorbed into the ceramic matrix and get encapsulated. We take a potsherd, clean it, crush it and then perform lipid extraction", Correa-Ascensio said.

Researchers for the first time have used this method to identify an ancient alcoholic beverage. This process could also be utilized to research the history of other cultures' use of alcohol, say experts. Ancient Mexican pottery proves that residents of Teotihuacan used to make and drink a milky alcoholic mixture.

Scientists said that there is possibility that this liquor helped the city's residents to have the important nutrients at the time of shortfall in staple foods.