Clean the lilac berries, pluck them from the panicles and wash them thoroughly. Pour about 1 litre of water into the lower part of the steam juicer. Layer the lilac berries and sugar in the perforated insert and leave to steep for about 2 hours.
Then bring the water to the boil and extract the juice for about 45 minutes. 15 minutes before the end of the cooking time, fill 1 bottle and pour over the fruit. Fill the juice into bottles and close them well.