Remove the zest of the lemons and, after removing the white skin, cut the wedges into large pieces.
Peel the grapefruit, remove the white skin and cut into large pieces. Put the fruits in a large saucepan and fill up with a little water, the flesh should be just covered. Add the zest and cook for 5 minutes. Then weigh the contents. Don`t forget to deduct the pot weight.
Fill up everything together with the preserving sugar 1: 1, add 1 kg of sugar to 1 kg of fruit pulp and cook according to the instructions. Stir in the slivovitz.
Fill into jars that have been rinsed with hot water and close immediately.