Feature Articles: Cooking and Produce
Enjoy and preserve fresh blueberries
Susan Mills-Gray, Nutrition and Health Education Specialist, Extension Professor, University of Missouri Extension
Blueberries contain cancer-fighting antioxidants and may play a role in reducing your risk for heart disease. Here are some tips for making the most of your blueberries.
If you are picking or purchasing fresh blueberries, you should know:
- Blueberries, even those on the same bush, do not all ripen at
the same time. Under normal growing conditions, blueberries ripen
over a period of three to four weeks.
- Blueberries are ready for harvest no sooner than three to four
days after the fruit becomes fully blue. Blueberries can remain on
the plant for seven to 10 days after they have become ripe without
significant loss in quality. However, they will not continue to ripen
after being picked.
- Ripe blueberries should have a completely uniform blue color.
Fruit with a red tinge is less mature and will not be as sweet as
more mature berries.
- For best results, blueberries should be harvested carefully when
they are dry and fully ripe. It is best to wait a few hours after
a rain or heavy dew before harvesting. Wet berries are more susceptible
to decay-causing organisms and often leak juice, causing them to
resemble overripe berries.
- Ripe blueberries are easily removed from the bush. Fruit should
be removed with the thumb and forefinger, keeping the hand cupped
under the berry to avoid dropping it. A whitish, dusty appearance
(bloom) on the blueberry is desirable.
- Harvested blueberries should never be allowed to remain in the sun because the dark berries absorb heat easily.
Blueberries are not as perishable as most other berries. While other berries keep their quality for a day or two after purchase, blueberries will keep for about a week if they are handled properly. Use care in working with blueberries as they bruise easily. Put blueberries in a plastic container and refrigerate them as soon as possible. Do not wash blueberries until you are ready to use them — the added moisture will hasten the growth of mold.
Only ripe, full-flavored blueberries should be frozen. Washing blueberries before freezing can result in a tough-skinned product. Instead, wash them after thawing. If you must wash blueberries before freezing, sort the berries and wash them quickly in cool water. After washing, spread the berries in a single layer on a metal tray. Allow the berries to dry so they won’t stick together, then freeze them until solid. Finally, pack the berries in freezer containers and label. Blueberries may be frozen alone in containers or covered with cold, 40 percent sugar syrup (3 cups of sugar to 4 cups of water).
Blueberries can also be pureed before freezing. Wash the blueberries before pureeing them in a blender or food processor. Mix 1 cup sugar into each quart of pureed berries. Stir until the sugar is dissolved and pack into containers, leaving 1-inch of space at the top of each container.
Berries may be canned in water, juice or syrup. Heat about 1 gallon of water to boiling for each pound of berries. Blanch berries in boiling water for 30 seconds. Drain. Place 1/2 cup hot syrup, juice or water into each warmed jar. Pack hot berries into hot jars, leaving 1/2-inch headspace. Cover with lids and process in a boiling water bath canner (15 minutes for pints and 20 minutes for quarts).
Drying blueberries produces a fair product — the berries become leathery and pliable, but retain little flavor. Blueberries do not make good fruit leathers, unless they are used in combination with other fruits. Wash and drain blueberries before plunging them into boiling water for 20 seconds. Put berries into cold water immediately to stop cooking. Drain well and spread out to dry. It will take 24 to 36 hours for the berries to dry.
Enjoy these recipes:
Yield: 2 cups
- 1¼ cups blueberry juice
- 1½ cups sugar
- 1/4 cup corn syrup
- 1 tablespoon lemon juice
Combine ingredients in a saucepan. Bring to a rolling boil and boil
1 minute. Remove pan from heat and skim off foam. Use syrup immediately
or refrigerate to use later.
To can for later use:
Pour syrup into hot half-pint jars, leaving 1/4-inch headspace. Process for 10 minutes in a boiling water bath canner.
Frozen blueberry pie filling
Yield: 5 pints
- 12 cups blueberries
- 3 cups sugar
- 3/4 cup cornstarch
- 1 tablespoon grated lemon peel
- 1/4 cup lemon juice
Wash and drain blueberries. Combine sugar and cornstarch in a saucepan. Stir blueberries into sugar mixture and let stand until juice begins to flow from the berries, about 30 minutes. Add lemon peel and juice. Cook over medium heat until mixture begins to thicken. Ladle filling into freezer containers or bags, leaving 1/2-inch headspace. Cool to room temperature for 2 hours before freezing.
Last update: Monday, July 17, 2017