Building a Reference Library of Teas

Science correspondent Nicola Davis investigates the strange story of Tam O’Braan and his attempts to grow tea in Scotland. In episode two, Nicola hears how Tam’s network of Scottish tea growers began to have suspicions about exactly what he was selling and where it came from, and how cutting edge science helped provide some answers. Help support our independent journalism at theguardian.com/sciencepod