Why do pineapple and kiwifruit have proteases?
All fruits will have some proteases but pineapple and kiwi fruit have far more. Exactly why is not known but it is probably to repel pests. Animals and bacteria are made up of proteins so the proteases will essentially digest any pests that attempt to feed on the fruit. This is also the reason why your mouth tingles if you eat too much of them. The proteases start to digest the skin of your mouth. But don’t worry – in small quantities it is quite harmless!
