Nowadays, cans have a lining in them that prevent this from happening. Although the tin on the lids aren't lined, so, yes, you are having some chemical reaction taking place. At our restaurant, and any other one I have been involved in, we just pour the remainging stuff in a washed out salad dressing container. Cut a small hole in the lid and take it from there. Good luck!
114 oz cans? Up here in Canada they are 100 oz cans. You guys are weird.