Making freezer jam
Raspberries, strawberries and blackberries work well in uncooked freezer jam recipes. You must store uncooked jams in the refrigerator or freezer. You can hold them for several weeks in the refrigerator and up to a year in the freezer. If you keep them at room temperature, they will mold or ferment in a short time. Once you open the container, keep refrigerated and use the jam within two to three weeks.
Sort and wash fully ripe fruit. Drain. Remove caps and stems from berries and crush. If you use frozen fruit, the preliminary steps for preparation have already been done. The label you put on the container of fruit should state how much fruit and sugar you added to the fresh fruit before freezing. Subtract the sugar added from that called for in the freezer jam recipe.
Follow the instructions on the powdered pectin package or refer to the following basic recipe. The basic recipe for Uncooked Jam with Powdered Pectin is:
- 2 cups crushed berries (about one and 1/2 quarts of berries)
- 4 cups sugar
- 1 package powdered pectin
- 1 cup cold water
To Make the Jam: Measure two cups of prepared fruit into a large mixing bowl. Add the sugar, mix well, and let stand for 20 minutes. Stir occasionally.
Dissolve powdered pectin in one cup cold water in a saucepan and bring to a boil and boil for one minute. Add pectin solution to the fruit and sugar mixture. Stir vigorously for two to three minutes until the sugar is completely dissolved and no longer grainy.
Freezer jam is less firm than cooked jam but has more of a fresh-fruit taste.
Pour the jam into clean freezer containers or canning jars, leaving one-half inch headspace. Cover the containers and let stand for 24 hours, or until the jam has set and become firm. This quantity makes about five or six half-pint jars or freezer containers.
When jam comes out of the freezer, thaw overnight in the refrigerator. If the jam is too firm, you can soften it by stirring. If it tends to separate, stirring will blend it again. If freezer jam is too soft bring the jam to a boil in a saucepan on top of the range for one minute and it will thicken as it cools. Freezer jam is less firm than cooked jam but has more of a fresh-fruit taste.
Plastic freezer containers with tight-fitting lids work well for storing freezer jams and jellies.
If you wish to reduce the amount of sugar, use a modified low- or no-sugar pectin that allows you to do so. Follow the pectin package directions carefully.
Reviewed by Glenyce Peterson-Vangsness, University of Minnesota Extension educator, 2010.