I emailed a company that markets canned seafood products a few years ago. I was questioning why the did not date their products and a lady replied that they have no dates when it would be unusable, she said that i may want to use it soon if it had been through several extreme temp changes. I've always heard its ok as long as its not rusted or swelling its probably good but may lose taste and nutrition. I don't buy that it loses nutrition, the nutrients don't magically disappear.