Salt is added to pineapple in several countries because it neutralizes the acid. These pineapples, not like the ones we have in Europe and the American continent (guessing here), are so acid they can burn your tongue.
Pin Number - ATM pins were originally supposed to have six digits. The inventor changed it to four digits, however, because his wife claimed she could only remember that many numbers.
Salt is added to pineapple in several countries because it neutralizes the acid. These pineapples, not like the ones we have in Europe and the American continent (guessing here), are so acid they can burn your tongue.