When plums are barely ripe, they're high in pectin and natural acid (which helps the pectin set) so you don’t need to add lemon juice or jam sugar to help the jam set. Use this jam, along with whipped cream, to fill a classic Victoria sponge cakes.
Ingredients
- 1kg firm, barely ripe Victoria plums or damsons
- 1kg preserving or granulated sugar
Method
- 1. Halve the plums or damsons, remove the stones (reserving a handful), then place the plums in a preserving pan with 150ml water. Bring to the boil, then reduce to a simmer for 40 minutes until the plums have broken down. Use a long-handled wooden spoon to help break down the plum flesh.
- 2. Meanwhile, using a nut cracker, crack open the reserved stones to extract the kernels. Blanch the kernels for 1 minute in a pan of boiling water. Drain.
- 3. Remove the pan from the heat, then stir in the sugar and blanched kernels. Return to a low heat until the sugar has dissolved, then bring to the boil and bubble for 10 minutes before testing whether it has set or the thermometer reaches 105°C – if you don’t have one, try the set test. You can find this method in our How to make jam article. Skim any scum from the surface, then allow to stand for 10 minutes.
- 4. Pour into warm, sterilised jars (again, see our How to make jam article.) Seal immediately with waxed discs. Secure each jar with cellophane covers and elastic bands, then add fabric covers and labels, if you like.
Chef's tip
Adding the kernels of stone fruits imparts a delicate flavour. Traditionally, the kernels are potted with the jam but you can remove them. Use this jam, along with whipped cream, to fill a classic Victoria sponge cakes. Learn How to make jam.