I just ,this week, started rotating canned food after 3 years.
Im talking in cans, not the stuff in glass thats home canned.
After 3 years the cans start showing signs of rusting.
So you gotta keep an eye on it, and turn it evry few months.
Food in glass is much better,
I also store seeds, sugar, rice,flour,corn meal and salt in glass quart canning jars. It keeps great for years, I have some thats 6 years old and still good, we are starting to replace some sugar ,salt, with some that cost twice as much.
Jim