Água de Coco

The coconut palm reached Brazil early in the colonial period, brought by the Portuguese from their possessions on the routes to the Indian Ocean, and it took hold along the warm Northeastern coast, which remains the country's coconut belt. Drinking the water of the green nut is as old as the palm's presence there, the simplest refreshment in the tropical heat. The image of the beach coconut vendor — a stack of chilled green cocos, a machete, and a straw — became fixed across the whole Brazilian coast, from the Northeast to Rio, in the 20th century, and packaged coconut water later grew into a major industry exported worldwide. The drink remains, above all, a thing of the sand and the sun.

Cool and almost colourless, faintly cloudy, with a clean, very light sweetness and a soft, slightly saline, nutty note that says coconut without any of the richness of the milk. Drunk straight from the shell through a straw it is thin and watery in the best way, deeply thirst-quenching rather than filling. Best ice-cold; warm, it turns flat and faintly sour. After the water, the spoonful of tender white jelly scraped from inside is a soft, mild bonus.

There is no preparation beyond opening the nut. The water is the liquid endosperm of the immature green coconut, at its most plentiful and most lightly sweet before the flesh thickens; as the nut ripens this water is gradually absorbed into the hardening white meat, which is why mature brown coconuts hold little. Its balance of potassium, sodium and other electrolytes is close to that of human plasma, making it naturally isotonic, which is the basis of its reputation as a rehydration drink. Sealed inside the shell it stays sterile and fresh; once opened it should be drunk promptly before it oxidises and ferments.