After using utensils to prepare/eat longkongs, the utensils are very sticky (by far stickier than for any other types of fruit that I have tried so far). I tried to use soap and dishwashing liquid, as well as letting the utensils in the water for a few hours, but the utensils are still sticky.
How can I clean utensils (e.g., knives) used to cut longkongs?