We can trace three distinct eras of human history by following our taste for spicy heat. Even though piquancy is designed to be aversive - it is plants’ defensive chemicals to repel pests - people have always been drawn to the thrill of the disquieting. Ginger was one of the first foods on the move, its thunderous warmth making it popular cargo for Austronesian sailors 6000 years ago. This marks the start of early intermingling, when commodities and ideas began to spread overseas.
Pepper defines another era. A reliable and versatile whack of heat that travelled well, it was greeted hungrily - in the Middle Ages, 90 per cent of spice imports to Europe were Indian peppercorns, and the Chinese were reportedly taking ten times the quantity. Explorers set out in search of new routes to satiate the hot desire for pepper, so redrawing world maps and fuelling the European Age of Discovery.