Agreed - mostly. Canned tuna goes bad around a year after the expiration date, and you know it as soon as you start opening the can. I don’t even experiment with keeping fish past its best by date any more because of the smell when it goes bad.
Other foods may last several years past the label date. Canned fruit does very well, and I’m testing to see just how long, but it’s at least three years beyond the labeled “best by” date. Tomato sauce gets a metallic taste by two years after the label date, but it’s still okay.
Acidic foods are the worst offenders.I don’t buy canned tomatoes much ahead. OTOH, canned salmon is pretty stable. Green beans, corn, spinach, white potatoes, chicken all have proven to be quite stable.
I read an article by a major European canning association. They are pretty clear on the safety of most canned foods for many years. Storage is key.
Also note that the cans usually say “best by” not “sell by”.
I think the real point is that for a 6 month supply of stored food, one doesn’t need to get too exotic or spend too much. I buy canned beef from a company in Ohio. Nothing in the can but beef,water and salt. Keystone. Wal Mart also carries it in stores in our region. Very good product.
We have home canned fresh caught N. Pacific tuna. I wait a year before I even open it because the flavor is so much better.
If you open it and then wait a year to eat it I can see where there would be a flavor problem.
Find a brand of canned tomatoes that has the inside of the can coated. Those shouldn’t pick up the metallic taste as much.
Tuna is a very high priced item. There are only 2.5 oz of meat inside a small can.