For the quince jelly, scrape the quinces with a tea towel. (Pear quinces have a very fine pelt) Remove blossom and stem end, as well as the core.
Slice the fruit and bring to a boil, covered with water. Do not fill the bowl too full, mass boils over easily and burns easily.
Boil quinces for 45 minutes and while still hot, pass through a dish towel into a bowl.
For the jelly, weigh the juice, according to the amount to a kilo of juice add the ingredients listed above and bring to a boil. Boil for 1 to 2 minutes and then pour the quince jelly into sterile twist off jars.