Just-picked corn contains a great deal of sugar and very little starch, which is why ultra-fresh corn on the cob is such a treat. However, problems arise very soon after harvest, when natural sugars start to convert into bland starch, and the process only continues during transport or storage.
Any tactic for offsetting flavor deterioration seems worth a try, so we boiled out-of-season corn four ways: in 1 gallon of plain water, in the same amount of water mixed with 1 cup of milk, in water mixed with 1 cup of milk and 4 teaspoons of sugar, and in water sweetened with 4 teaspoons of sugar (our go-to test kitchen technique). The corn cooked in plain water was virtually tasteless, as was the sample pulled from the water-milk bath.
So although adding milk proved unnecessary, a little sugar did the trick—4 teaspoons per gallon of plain water brought out the bright flavor of the kernels. Why? Corn contains proteins called prolamines, whose bitterness becomes more pronounced as the sugar concentration declines. When sugar is added to the cooking water, it’s absorbed by the kernels, helping restore their sweetness and mask bitterness.
