Since heat rapidly converts the sugar in corn to starch, it is very important to choose corn that is displayed in a cool place. If shopping for corn in the supermarket, make sure it is refrigerated. If purchasing corn at a farmer’s market or roadside stand, make sure that if the corn is not refrigerated, it has at least been kept in the shade, out of direct sunlight.

Look for corn whose husks are fresh and green and not dried out. They should envelope the ear and not fit too loosely around it. To examine the kernels, pull back part of the husk. The kernels should be plump and tightly arranged in rows. You can test for the juiciness of the corn by taking your fingernail and pressing on a kernel. Corn that is fresh will exude a white milky substance.

To enjoy corn’s maximum flavor, purchase it on the day you are going to cook it since corn has a tendency to lose its flavor relatively rapidly. Store corn in a plastic bag in the refrigerator. Do not remove its husk since this will protect its flavor. To enjoy its optimal sweetness, corn should be eaten as soon as possible.

Fresh corn freezes well if placed in heavy-duty freezer bags. To prepare whole ears for freezing, blanch them first for seven to eleven minutes depending upon their size (larger ears take a longer time to blanch than smaller ones). If you just want to freeze the kernels, first blanch the ears for about five minutes and then cut the kernels off the cob at about three-quarters of their depths. Whole corn on the cob will keep for up to one year, while the kernels can be frozen for two to three months.