Cut the peeled pineapple, peeled mango and peeled persimmon on small cubes. Add them to a large bowl. Also add the sugar, seeds from one vanilla bean, citric acid and juice of one lemon. Combine well and place in a fridge overnight, so that fruit macerates.
Cook the jam
Place a large pot over medium high heat. Add the macerated fruits with all the liquid to the pot. Wait until the mixture starts to boil, then lower the heat and cook for about 40 minutes. Stir regularly to prevent burning.
Spoon hot pineapple jam into hot sterilized jars and cover immediately with sterilized lids. Let the jars cool slowly. Store in a dark place for up to 3 months.