makes: approximately 1.75kg
calories per tbsp: 40
fat per tbsp: 0
saturated fatper tbsp: 0
suitable for freezing: no
- juice of 1 lemon
- 1kg blackberries
- 1kg pears, peeled and cored
- 1kg packet jam sugar
- sugar thermometer
1. Pour the lemon juice into a large pan and add the blackberries and pears. Place the pan over a low heat and stir until the juice starts to come out of the blackberries. Increase the heat and bring to the boil, then reduce the heat and simmer gently for 30-45 mins, stirring occasionally, until the fruits are very tender. Remove the pan from the heat.
2. Mash the fruits and push through a strainer to remove the seeds.
3. Pour the fruit purée back into the cleaned pan and add the sugar. Place the pan over a low heat and stir until the sugar dissolves. Bring the mixture to the boil, then boil it rapidly for about 5-10mins, or until it reaches 105°C
4. Remove the pan from the heat and test that it reached setting point, if not, boil for 1-2mins more and test again, and repeat until setting point is reached.
5. Leave the jam to cool for about 20-30 mins, then pot in warm, sterilised jars. Place wax discs against the surface of the jam and leave to cool completely before covering the jars and labelling.
6. The jam may be stored in a cool, dry, dark place for up to 6 months. Once opened, store the jars in the fridge.
Testing the setting point
Jams are generally boiled to 105°C, but the wrinkle test is an extra check to make sure that setting point has been reached. Before starting to cook the jam, put a couple of small plates or saucers in the freezer. When the jam reaches 105°C, remove the pan from the heat to prevent over-cooking it and spoon a little of the jam on to one of the cold plates or saucers. Leave the jam for a few minutes, then push it with your fingers. If the surface wrinkles, the jam is ready – if not, cook it for a little longer and test it again.