Place 45 ml (3 tbsp) of the orange juice into a small basin and sprinkle over the gelatine. Leave to soak while cooking the strawberries.
Hull the strawberries, put them into a pan with the remaining orange juice and mash them lightly to break them up slightly. Over a low heat cook the strawberries for 3-4 minutes until they are just soft. Turn off the heat, stir in the soaked gelatine and keep stirring until it has dissolved. Stir in a few drops of red colouring if liked, then leave the jam to cool.
Leave the jam to cool for 10 minutes then stir in the Hermesetas Granulated. Pour the jam into a clean, warm jar, cover and label. Leave the jam to cool completely then store in the refrigerator and use within 1 week of opening.