According to Ronald L. Prior, a research chemist and nutritionist with the USDA's Arkansas Children's Nutrition Center in Little Rock, a one-cup serving of blueberries delivers as much antioxidant power as five servings of grapes, peaches or broccoli.

If you're shopping for blueberries:

* Most of the blueberries we see in markets are cultivated, not wild. These blueberries are almost never sold loose but instead in pint containers that are usually covered with plastic. Look through the plastic for berries that have a white, chalky cast to them, a sign of freshness. If they do not roll around freely in the container when shaken slightly, they may be overripe or crushed inside, so keep looking.

* When you get the berries home, remove them from the container and put them in a bowl. Pick out the moldy or crushed berries and discard them. Cover the bowl and refrigerate. To keep the berries from becoming mushy, do not wash the berries until you're ready to eat them; then wash thoroughly.

* Don't keep blueberries more than two or three days in the refrigerator. If you buy too many or don't use them promptly, wash, drain well and freeze them loose on a baking sheet, then store in a resealable plastic freezer bag until ready to use.

Sources: Washington Post research; www.wildaboutberries.com