Back in the 70's I was taking groups out from a camp all summer long for several years. The first thing was I bought a good supply of dehydrated food from Siedel... I think thats how you spell it. All went pretty good the first year and I had enough for the second year to. We had beef stew one night and found (we guessed it was the onions) that you couldn't use them after a year. We all had such bad gas and there was a terrible storm so we had to close up the tent too. Whew! I got into store bought foods real soon after that.