Signs of beer brewed 5,000 years ago

Residue on pottery from an archeological site has revealed the earliest evidence of beer brewing in China - done 5,000 years ago, researchers said.

The artefacts, found in Shaanxi province, show that people of the era had already mastered an "advanced beer brewing technique" that had elements from the East and West, according to a study in the Proceedings of the National Academy of Sciences, a peer-reviewed US journal.

Yellowish residue gleaned from pottery funnels and wide-mouthed pots also reveal the recipe, from the traces of ingredients that had been fermented together - broomcorn millet, barley, a grain known as Job's tears, and tubers, AFP reported.

"The discovery of barley is a surprise," said lead author Wang Jiajing of Stanford University. He said it is the earliest known sign of barley in archeological materials from China.

"This beer recipe indicates a mix of Chinese and Western traditions - barley from the West; millet, Job's tears and tubers from China," he said.