A great corn on the cob must tread the line between under- and overcooked. Here’s why – and how to do it

Humans 28 September 2022

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FRESH sweetcorn is one of the delights of late summer and early autumn. Its sweetness derives from a genetic variant that emerged some time after corn was first domesticated by people in Central America, about 9000 years ago. This mutation, called su1, stops the plant turning sugar into starch while it grows. Some sugar is instead converted into a different carbohydrate, phytoglycogen, which gives sweetcorn its creamy texture.

After harvesting, enzymes begin converting the sugar into starch, so sweetcorn is best eaten on the day it is picked. Some older varieties of corn can lose as much as half of …