Just been using up some stuff that I stored about 15 years ago in the basement. Here's what lasted and what didn't:
1) egg noodles, boiled them, worked just fine
2) wheat berries, ground them to make indian Roti bread, worked fine
3) nitro sealed corn meal, works fine
4) freeze dried lentils, no problem
5) white rice , a little bit crumbly when cooked but ok
What didn't work:
1) Dehydrated mashed potatoes with 'butter'-like substance, went rancid.
2) canned tomato sauce, probably ok but had dark color and I didn't want to risk ruining my beef stew
3) canned premixed pancake mix, had gone flat and had unpleasant smell, some active ingredient had reacted slowly