As with other fortified wines (port, marsala), madeira came about through necessity: wines that tasted good on the island had turned distinctly manky by the time they’d been transported back to Blighty but adding a healthy dollop of spirit alcohol was just the thing to stabilise the stuff. In madeira’s case, the story does not stop there. Outgoing ships bound for the Indies would revictual on Madeira and the practice of taking on barrels as ballast became commonplace. Traversing the equator twice (once on the way there, once on the return leg) had a remarkable effect on the wine, adding depth and complexity. It was discovered that the gradual heating of the wine transformed it into something altogether more worthwhile. Still, today, barrels of the finest madeiras are placed by open, south-facing windows in the winery over the summer months where they are slowly “cooked” by the sun. For cheaper wines, a period of estufagem (i.e. “cooking”) is undertaken in stainless steel vats. The end result is a remarkably stable product. Unlike port or sherry, madeira can be left in a decanter for a couple of months or more with no adverse effect on its quality.