Blackberry Port Jam is a low-sugar cooked jam made with Pomona’s Pectin. Pomona’s Pectin contains no sugar or preservatives and jells reliably with low amounts of any sweetener. See below for where to buy.
This recipe was adapted from Better Homes & Gardens Special Interest Publication Canning Magazine by Mia Valcarcel, who wanted to make it with Pomona’s Pectin.
Yield: about 4 cups
Before You Begin:
Prepare calcium water. To do this, combine ½ teaspoon calcium powder (in the small packet in your box of Pomona’s pectin) with ½ cup water in a small, clear jar with a lid. Shake well. Extra calcium water should be stored in the refrigerator for future use.
Blackberry Port Jam Ingredients
2 cups mashed blackberries (about 4 cups whole berries)
1 ½ teaspoons calcium water
1 cup port wine
2 tablespoons lemon juice
½ cup sugar
1 ½ teaspoons Pomona’s Pectin powder
Additional sugar if needed (depends on how tart your blackberries are)
¼ teaspoon ground cinnamon (optional, depends on your port flavors)
Blackberry Port Jam Directions
1. Wash jars, lids, and bands. Place jars in canner, fill canner 2/3 full with water, bring to a boil. Turn off heat, cover, and keep jars in hot canner water until ready to use. Place lids in water in a small sauce pan; cover and heat to a low boil. Turn off heat and keep lids in hot water until ready to use.
2. Measure mashed blackberries into sauce pan.
3. Add calcium water, port wine, and lemon juice, and mix well.
4. Measure sugar into a bowl. Thoroughly mix pectin powder into sugar. Set aside.
5. Bring fruit mixture to a full boil. Add pectin-sugar mixture, stirring vigorously for 1 to 2 minutes to dissolve the pectin while the jam comes back up to a boil. Once the jam returns to a full boil, remove it from the heat. Taste the mixture to see if you need to add more sugar. This will depend on how sweet or tart your blackberries are. If adding more sugar, turn the heat back on, stir well while mixture returns to a full boil, then remove from heat. Add cinnamon now if desired to help boost the flavors.
6. Fill hot jars to ¼” of top. Wipe rims clean. Screw on 2-piece lids. Put filled jars in boiling water to cover. Boil 10 minutes (add 1 minute more for every 1,000 ft. above sea level). Remove from water. Let jars cool. Check seals; lids should be sucked down. Eat within 1 year. Lasts 3 weeks once opened.
Note from Mia: The port I used is from a local Maryland vineyard and contained overtones of chocolate and raspberry. The original recipe called for cloves, but I used cinnamon instead. I think it boosted the flavors more than cloves would have.
For more inspiring recipe ideas, see Preserving with Pomona’s Pectin: The Revolutionary Low-Sugar, High-Flavor Method for Crafting and Canning Jams, Jellies, Conserves, and More by Allison Carroll Duffy and the Pomona’s Partners, published by Fair Winds Press, June 2013, and available in paper or ebook everywhere books are sold.
Pomona’s Pectin is available at your local natural food store, food co-op, and many farm stands. Find it also at Sur La Table and a growing number of more conventional grocery stores with natural food sections (Wegmans, Hy-Vee, Rosauers, Nugget Markets, Coborns, Fairway, and others). If you can’t find a store near you on our store locator, you can order from our website or many other online sellers.