1kg mixed berries (Whatever mixture you like – you can even use those leftovers that are hiding in the freezer from the last visit to the PYO!) I’ve used cherries, blackberries, redcurrants, blackcurrants.
1kg granulated sugar
100ml apple juice
You will also need:
A large preserving pan
A SuperFast Thermapen
3 or 4 jam jars (I’m reusing old jars)
Place the sugar into an ovenproof bowl and place into a cold oven.
Remove the lids from the jam jars and sterilize them by placing upside down onto the shelf in the oven alongside the sugar.
Turn the oven on to 130ºC/Gas Mark 1 – the reason behind placing them in a cold oven is that if you were to put them straight into a hot oven they may crack so let them heat up gently.
Place the fruit into your preserving pan, add the apple juice and over a low heat simmer until soft (approx. 15-20 minutes).
The apple juice contains a good level of pectin which will help with setting and avoids the need for special jam sugar or the addition of commercial pectin. This bit of simmering is important to soften the skins of the fruits if you don’t get them soft at this stage when you add the sugar it’s game over and the skins will go like leather.
When you’re sure the skins of the fruit are soft enough add the warmed sugar and stir until completely dissolved.
The sugar is dissolved when you can’t feel it on the bottom of the pan when you stir, and if you lift out the spoon to check there will be no sugar granules visible.
Turn up the heat and boil on a rolling boil, testing with your Thermapen occasionally until the setting point is reached (for this jam 106ºC). Stir occasionally to make sure nothing sticks to the bottom of the pan.
Turn off the heat and remove any frothy scum from the surface of the jam with a spoon.
Remove the jars from the oven. Be careful because they will be very hot!
Fill the jars right to the very top with the jam. You need to fill them right to the very top. I find the best way is to ladle it into a jug and use a jam funnel – I’m a bit messy at the best of times and this gets all the jam in the jar!