Beer recipes change over time. Hops, for example—which give many a modern brewski its bitter, citrusy flavor—are a relatively recent addition to the beverage, first mentioned in reference to brewing in the ninth century. Now, researchers have found a surprising ingredient in residue from 5000-year-old beer brewing equipment. While excavating two pits at a site in the central plains of China, scientists discovered pottery fragments from pots, funnels, amphorae, and stoves (stove fragment pictured).
