Wednesday, May 22, 2013

Out-dated food and Shelf life

One of the most frequent questions I get in my emails is from people asking about the shelf life of various foods, and the other most common question is what to do with out-dated food.  Is it safe to eat?  What should they do with it. 
The shelf life of foods depends on more than things such as the 'expiration' date stamped on the can or box, if it's a commercially-produced food item.  Other things come into play regarding how the food is stored after it comes into your possession.  Do you store your food in a cupboard in your heated kitchen?  Well, you have one thing going right.  It's dark in there.  Dark is good for any food that the light could get to through the container it's stored in.
Therefore plastic bags and bottles, glass jars, and things like transparent containers such as Tupperware are the sort of thing you want to store in a dark place such as a cupboard if you use them to store food in.  It's one of the reasons that good cooking oils come in tinted bottles.  It keeps the light from accelerating the process of turning oils rancid.
Another thing that can extend the shelf life of your food storage is cooler temperatures.  Not everyone has a temperature-controlled food storage room kept at a consistent cool temperature and low humidity.  But there are ways to keep your food cooler.  Putting food in low cabinets near the floor is a cooler location than overhead cabinets.  Your overflow food storage can be stored under beds or in closets, where it's also cooler.  If you have a basement and it's not too humid, that's another good place to store foo. 
Garages can be used if canned food won't be exposed to below-freezing temperatures.  I've used mine in the summer for overflow.  I've also set a few cases of canned food in our barn for the summer.  One of the grocery chains here runs a caselot sale in May and since I know it won't be consistently below freezing even this far north after the end of May, I can put canned goods in there.
Not all food is canned though.  I know the proper way to store long-term dry foods is to pack them in mylar in buckets with oxygen absorbers, but here's the problem I have.  First, I can't afford the mylar or the oxygen absorbers.  I get buckets free from the grocery store bakery so I can at least dump dry foods in those and store them like that.  And one of the main reasons I can do that is that we haven't gotten far enough ahead in the food storage game to consider any of it to be true long-term food storage.  More than once we've had to eat out of our storage down to the last bucket of flour and completely out of sugar. 
The white buckets do allow a bit of light through them, so I stack my buckets on boards or pallets in our barn and I throw old blankets over them.  Not only does this keep out light but it helps stabilize the temperature.  Another enemy of food storage is fluctuations in temperatures in the form of daytime heat and night time cooling, as well as seasonal changes in temperature.  Seasonal is not as bad as the daily swings between night and day.
The bottom line for storing food for the longest shelf life is to protect the food from light, heat, and air. 
Another thing that is important is rotation.  I didn't take this as seriously as I should have and I got lazy and used newer stuff, figuring I'd get to the older stuff before it got too outdated.  Now I find myself with outdated cans of green beans, tomatoes, cream of mushroom soup, tomato sauce, and others.  We've been cautiously using them anyway.  We check every can for swelling or leaking, and when we open it we look at the color and texture, and smell the contents.
The most deadly form of food poisoning, Botulism, is invisible and has no odor.  That is truly scary.  If in doubt, do not eat any canned food that you're suspicious of.  I feed the occasional suspicious can of food to our chickens, but there have been a few bulging cans that I didn't even want to use my can opener on, and we threw them away. 
Dry foods don't exactly go bad unless they're exposed to moisture and become moldy.  Dry foods just get rancid or stale.  The caselot sale usually has boxed macaroni & cheese on it, and when the kids were still at home it wasn't hard to get through a case before they expired.  There are 48 boxes in a case.  With just my husband and I it took a year or more to finish a case, but that wasn't so awful because the first case we bought after our last child got married and moved out had an expiration date about 18 months away.  The next year we bought another case, and that time it must have been some backstock because the expiration date was a mere 4 months away.  Two people, 48 boxes of macaroni & cheese, and 4 months to eat it?  Yeah, not gonna happen.  We managed to shove some off on the kids, but the last of that case was eaten 7 months after the 'expiration date' and although the cheese sauce was starting to taste flat and the noodles had a faint rancid smell, it was edible.
Beans take longer to cook when they get older but they usually store a long, long time.  We were given some "Y2K" beans someone stored and they just about never became soft.  Even then they were grainy.  And they were only about 12 years old when we cooked them.  I've heard of people eating beans they had stored for 25 years.  It comes back to how they were stored.
We got some rice from the same batch of Y2K food and it was fine.  It didn't take longer to cook and it tasted great.  It had been stored in rinsed-out one-gallon milk jugs.  The jugs had become brittle and we broke a few when we poured the rice out into bags.  There were soybeans in some of the jugs and they never cooked and we were unable to sprout them. My husband ground them and mixed them with chicken food.  I'm sure the protein was good for the hens.
Grains such as wheat, barley, oats, and rye can be stored literally forever.  They've found wheat in stone bins in the middle east and in the American southwest that has been stored for hundreds and thousands of years that was still good.  So good, in fact, that they were able to sprout it.  Moisture is the biggest enemy of grain, and it's important to make SURE your grains are dry when you pack them for storage.  They can get a mold on them that can sicken and even kill.
So what's the worst disaster I've seen in shelf-life failure?  A can of pineapple ice cream topping that literally exploded in the cabinet and covered everything in drippy bits of gooey sweet pineapple.  It was only stored for about three years and we have no idea why it blew it's lid
I welcome additional information to this post, as well as questions or stories about your food storage experiences related to out-dated food and shelf life.  Please make this an interesting and interactive blog by WRITING to me! 
Thank you


  1. Here is something I have noticed with dry beans, and it makes no sense but there it is. When you have a good batch, that cooks up fast, it will still be good years later. I started storing some food in the early seventies, and it took us years to work our way through the beans. They were fine. Sometimes you have a bad batch and no matter what you do, you can't get them to cook. Split peas for instance won't melt into mush but remain gritty, even after days in a slow cooker. I have seen this especially with chick peas. It is the only bean I always buy in cans now. Otherwise, I always have a 'stash' of dry beans and grains in kitty litter buckets with really good snap lids, in a darkish hallway closet. We eat them and buy new when we run out. So I am always good for a few weeks, but don't count on me to survive the zombie apocalypse.

    1. Thanks for your comments. I never thought about it being certain batches of beans that might just not cook.

      May your beans last longer than you expect if the zombie apocalypse come along! :D