Put the pineapple juice in a small bowl along with the red wine vinegar. Finely dice the pineapple and add.
Peel the ginger, core the chilli pepper and dice both very finely. Put together with 1 tablespoon oil in a saucepan and heat gently. Add the butter, sweat the curry powder and the five-spice powder briefly (not too hot, otherwise it will be bitter), then add the sugar and lightly roast. Add the pineapple with the juice and red wine vinegar and cook while stirring until the pulp crumbles easily. If necessary, add a little more boiling water. Stir in the tomato ketchup and cook for another 4 - 5 minutes over a medium heat.