Blackberry & Apple Jam

 

2 large cooking apples, cored and thinly sliced, cores reserved

3 pounds fresh blackberries

5 C. sugar

3 T. freshly squeezed lemon juice

2 to 3 T. blackberry or raspberry cordial, or liqueur (optional)

 

Prepare a hot water bath (see here). Place the jars in it to keep warm. Wash the lids and rings in hot, soapy water, and set aside.  Put the reserved apple cores in a piece of cheesecloth and tie the ends securely with kitchen twine into a sachet. In a preserving pot or deep pot, combine the apple slices, blackberries, and the sachet. Cover the fruit with water. Bring to a simmer over medium heat and cook for about 10 minutes, stirring frequently, or until the fruit is very tender and starting to fall apart. Remove the pot from the heat. Remove and discard the sachet. Using a sieve or fine strainer, purée the fruit by passing it through into a clean pan. Add the sugar, lemon juice, and cordial (if using). Return the mixture to a simmer over low heat. Continue to cook, stirring often, for 20 to 25 minutes or until the jam gels and the mixture reaches 220°F, measured with a candy thermometer. Test for gel after 20 minutes (see here).  Ladle the jam into the prepared jars, leaving ¼ inch of headspace. Use a nonmetallic utensil to release any air bubbles. Wipe the rims clean and seal with the lids and rings.  Process the jars in a hot water bath (see here) for 10 minutes. Turn off the heat and let the jars rest in the water bath for 10 minutes. Carefully remove the jars from the hot water canner. Set aside to cool for 12 hours. Check the lids for proper seals (see here). Remove the rings, wipe the jars, label, and date them, and transfer to a cupboard or pantry. Refrigerate any jars that do not seal properly and use within 1 month. Properly sealed jars will last in the cupboard for 12 months. Once opened, refrigerate, and consume within 1 month.