Blackberry-Apple Jam

• • • Makes 2½ pints • • •

Together with raspberries and blueberries, blackberries compose a category of fruit known in Italian as frutti di bosco, or “fruit of the woods.” Which is a fancy way of saying mixed berries. You can make this jam with all three, but I prefer just blackberries for their deep color and intense, winey flavor. These berries are low in pectin and need a little help to set. Rather than add commercial pectin, I use a small Granny Smith apple, which gives this jam just the right consistency and an extra hit of tartness. This is an excellent jam to use in Favorite Jam Crostata (page 105).

6 cups (1 kg) blackberries

1 small Granny Smith apple

5 cups (1 kg) vanilla sugar (see page 57) or sugar

3 tablespoons freshly squeezed lemon juice

Equipment

5 sterilized ½-pint jars and their lids

Food mill

Basic water-bath canning equipment (see page 15)

1 • Put the berries in a nonreactive heavy-bottomed saucepan or preserving pot and mash them up a bit with a potato masher or wooden spoon. Cut the apple into chunks and add it, including skin and seeds, to the pot. Cook the fruit over medium heat until the apple pieces are soft, about 30 minutes. Remove from the heat. Puree the mixture through a food mill fitted with the disk with the smallest holes, catching the fruit puree in a bowl. Discard the solids left in the mill.

2 • Measure the puree into a clean pot. You should have about 5 cups. Stir in the sugar and lemon juice. Bring the mixture to a boil over medium-high heat. Cook at a lively simmer, stirring often, until the puree has begun to thicken, 20 to 30 minutes. Watch out for spattering.

3 • Continue to boil until the mixture reaches 220°F. Or use the freezer plate method to test for doneness as described on page 83.

4 • Ladle the hot jam into the jars, leaving ¼ inch headspace. Wipe the rims clean if necessary with a clean, damp cloth, and screw the lids on the jars.

5 • Process the jars in a boiling-water bath for 10 minutes (see Water-Bath Canning, page 15). Remove the jars and set them upright on a clean kitchen towel. Let cool to room temperature before storing in a cool, dark place for up to 1 year. Refrigerate after opening. Store any jars that fail to seal properly in the refrigerator and enjoy those first.