Firmly cover the jars with lids before putting them in to an oven at 300ºF/Gas mark 2 until the juice has run well

Remove from the oven carefully remove the lids and turn out the fruit into a jelly bag or muslin overnight

Measure the juice and take the correct proportion of sugar

Add the sugar to a large heavy-bottomed saucepan or jam pan and warm on a low heat

In a separate pan, heat the juice to boiling point (but don't allow to boil)

Add the juice carefully to the warm sugar stirring all the time until the sugar has dissolved

Pour jelly at once into sterilised jars

Allow to cool before screwing the lids on firmly