I know i can put blessed salt on it but what if the food is bad?
Gone off, you mean? Don’t eat it. obviously.
Did you think by blessing it you would kill the food -poisoning bugs or something?
Laity can do blessings because of their baptism but it is not the same thing as a blessing by a priest or deacon.
"Bless us O Lord, and these your gifts which we are about to receive " is a basic blessing of food that we are encouraged to do.
Umm, yes, but I get the feeling the OP isn’t referring to Grace before meals, because of the puzzling reference to the food being bad,
Food could be cursed.