If I tell you that I put the pineapple pulp on my face as a natural mask... I've read that it's great to remove the dead surface cells and renew the skin - leave it on for 10 minutes and it does wonders. Well, after 5 minutes it started to burn, I had to wash it off - got rid of the dead cells for sure... :)
I usually get this burning feeling when I eat kiwi - probably it contains strong enzymes too...
I hope you feel better now!!!