Blueberries are less juicy than strawberries, making them an easy fruit to work with. The final amount of sweetener is up to you. I usually add the full 2 cups because my family prefers it sweet. Yield: about 8 half-pints.
Low-Sugar Blueberry Jam
• 12 cups (about 4 pounds) wild or cultivated blueberries, fresh or frozen
• 1⁄4 cup bottled lemon juice
• 1-1⁄2 to 2 cups sugar, maple syrup, or honey, divided
• 1⁄2 tsp cinnamon (optional)
1. Place a small plate in the freezer for testing the set. Combine the blueberries and lemon juice in a large, heavy saucepan over low heat. Let the berries cook for a few minutes, until they begin to break down, and then crush them with a potato masher.
2. After the mixture is juicy with crushed fruit, increase the heat and add 1-1⁄2 cups of the sweetener and the cinnamon, if using, and bring to a boil. Boil vigorously until the mixture is fairly thick, about 30 minutes. You’ll have reached the jam stage when a spoonful of jam dropped onto a cold plate holds its shape and you can leave a clean trail by passing your finger through the mixture.
3. Remove from the heat and skim off any foam. Taste the jam and add the additional 1⁄2 cup sweetener if desired. Ladle the hot jam into clean, hot half-pint jars, leaving a 1⁄2-inch headspace. Install new canning jar lids. Process in a boiling water bath or atmospheric steam canner for 15 minutes. Remove from the canner and allow jars to cool undisturbed for 12 hours. Store in a cool, dry place. Store opened jars in the refrigerator.
Find other low-sugar jam recipes and learn more about preserving with less sugar and added pectin in Making Low-Sugar Jams.
Andrea Chesman cooks, writes, and teaches in Vermont, where she lives on a 1-acre homestead. Find her books Serving Up the Harvest and The Backyard Homestead Book of Kitchen Know-How in our online store.