Preserve the taste and nutrients of summer with this homemade Wild Blackberry & Black Raspberry Jam made from freshly harvested berries. With full instructions for making black raspberry jam at home, canning blackberries and wild blackberry jam has never been easier, or more delicious.
For this recipe we will be following the Boiling Water-Processing method. Fill halfway, with water, bring to a boil and reduce to a simmer of 180 degrees F. Keep aside.
Harvest, wash and drain the berries.
Using a potato masher or wooden spoon, crush the berries until they are coarse. Measure out 4.5 cups of crushed berries with juice.
In a large saucepan, add the crushed berries, sugar, lemon juice, and vanilla. Stir well.
Over low-medium heat, slowly bring the mixture to a boil, stirring occasionally until the sugar has been dissolved.
Once the sugar has dissolved, increase the heat to medium-high and quickly bring the mixture the gelling point temperature of 220 degrees F, stirring constantly. Remove from heat once the temperature is reached.
Carefully ladle the hot jam into a *hot* sterilized mason jar, leaving 1/4 inch headspace.
Gently tap to remove any bubbles, clean the jar rim as needed, and top with the center lid and tightly screw on the metal band. Repeat until all jars are filled.
Place the sealed jars on the rack in the boiling-water processor that is elevated above the water. Once all of the jars are in place, lower the rack into the simmering water, ensuring the jars are covered by at least 1-inch of water.
Adjust the heat to medium-high, cover with a lid and bring the water to a rolling boil. Allow the water to boil for 15 minutes.
After 15 minutes, turn off the heat and remove the cover for 5 minutes. Carefully remove the jars from the canner and cool at room temperature for 12 hours.
Label and store jars for future use.
* You must sterilize your mason jars by boiling them in hot water before filling with jam to ensure no bacterial contaminants are left. This helps to reduce the incidence of food-borne illness.