Jewish law teaches that we should always bring salt to our table and dip bread in salt before eating it. The general explanation given for this is that our table is like an altar; just as sacrifices always included salt, our meals are to be similarly meaningful and thus include salt as well. On a more down to earth level, having just said a blessing on the bread we salt it to make sure we enjoy it as we eat it with gratitude to God. This is similar to the Sefer HaChinuch’s idea that the salt is simply to make the sacrifice tasty.
Rabbi Neil Fleischmann, “Salt of the Earth”, The Jewish Week (23 March 2012), 52.