Mix 300 ml water with lemon juice in a pot. Wash, peel, quarter and core the quinces. Cut quarters into pieces of about 1 cm and put them immediately into the lemon water. Simmer quinces in the lemon water for about 35 minutes
In the meantime cut the mango from the stone. Peel the fruit flesh and cut into cubes of about 1 cm. Finally add the mango to the quinces and let it boil up briefly. Add apple juice and let it cool down
Stir in the jam sugar and lemon zest and cook for approx. 3 minutes according to the instructions on the packet. (Then test the jelly.) Pour hot jam into boiled twist-off jars, close tightly and place on the lid for a few minutes, then turn over again
Waiting time approx. 1 hour