Tuesday, February 24, 2015

Exploding or Bursting Canned Foods


These are generic cans of food which leaked. These were dated 2009.  (Picture by preparednessadvice.com )


       When I was a child my parents kept a basement of emergency canned food.  It wasn't so much for fears of nuclear attack, I think, but more out of concern for a protracted Winter storm or a series of such.  At the time, we lived in a farming area in the Northeast, and some of the Winters there conjure my memories of Siberian Winter. I remember in particular many cans of grapefruit, pineapple, and tomato juice, and of course lots of fruits, vegetables, and canned meats.  I remember that most foods at that time, could be retained for ten years, regardless of the coded or uncoded dating system. After a couple of years in the basement, canned food was sent to the pantry upstairs for consumption.  In all those years I don't think we ever needed to throw a can away.

              I stock short term food supplies, and long term supplies in my own home, and I always have. The short term supplies are canned, just as they always have been, and I stock the #10 freeze dried canned varieties for long term storage, as these will last ten, twenty or even thirty years depending upon the type of food packaged. Both standard canned foods and the #10 freeze dried varieties are stored in areas which are both heated and cooled in order to lengthen their shelf life. These tend to be cool places year round.

              After about two years in temperate storage, I move the regular canned goods to the large pantry in the kitchen for consumption.  With a large family and a lot of sons, it has been rare that something hasn't been consumed and gets discarded.   I also have a couple of rules about buying canned goods.  I don't ever buy dented cans simply because I am buying for storage. I am content to pay a little bit more for the ability to store for a longer period.  In addition, I have noted that many of the generic cans of vegetables and fruit are now made of much thinner cans than they used to be. Some will actually click and pop back and forth if you test them with your thumb, which is something I was taught they should never do.

               A few years ago, after the 5.8 earthquake which destroyed homes and schools in the next county, I took a good look at all of our canned foods. During the quake, canned food was thrown up against the pantry door.  I checked everything for dents and bulges and I did throw a few things away in the event that there had been an unseen rupture.  A short time after, we had an explosion, or more correctly a seepage under pressure from a can of dog food which had a pull top lid.  The dog food was not stored in the area I had checked so closely.  Black foul smelling greasy spray had contaminated the cans around it, the shelf liner, and some cleaning products I kept nearby in another cabinet.  I threw out all of the sprayed materials and decided to keep a more careful watch of anything with a canned pull top lid.   I cleaned the area around it with gloved hands and bleach, before allowing the cabinet to dry and then later restocking.

                  This year while pawing through canned fruit while considering what type of cobbler to make for dessert, I found that a large can of peaches, which I had purchased about a year ago had leaked black bubbling fluid onto a number of other cans of fruit. 

 I donned vinyl gloves, removed the offending can and the five other contaminated ones. It seems that cans are being made far thinner than they used to be and that the seals to some of them are not holding. Bacteria is seeping into some of these cans and when a gas is eventually produced, the can either ruptures or explodes causing you to lose other cans, which after such severe contamination, cannot safely be cleaned and used. Interestingly, the offending can came from China as did the five others that needed to be thrown away.

In view of this, I am considering new canned storage guidelines which I have interspersed with some of the common sense old ones:

1. I think that in future, we will buy more freeze dried food in #10 cans. and fewer conventionally canned foods.

2. Since the cans from China and Thailand definitely seem thinner, and I tend to stock canned foods rather than use them immediately, I plan to avoid cans entirely which were not canned in the US.  I do occasionally buy food from the Asian grocery and I have not found the Japanese food to have poor canning quality control.

Also, with regard to the Chinese canned food, companies in China do not have the same liability as do American companies when selling canned goods here.   This is another good reason to be wary.

Liability for Products in a Global Economy by Dennis Campbell and Susan Woodley

3. I plan to consume acidic foods in cans more quickly than within two years.  Acidic foods would be tomato products, pineapple, mandarin oranges, etc.

4. In the past I did keep some canned Italian tomato sauce for pizza. I am considering buying it in glass jars now.

5. When you do buy canned foods, buy just three or four at a time, rather than twenty or twenty-five. You are more likely to get cans home without having them dented during packing or the trip home. The more cans they bag for you, the more dents are likely to occur. This will make stocking up during sales a bit more difficult, but perhaps we should pay a couple cents more and avoid the exploding can trap.

6. Always return or throw away any can that bulges from one end, seeps, has a dent over a seam, or clicks back and forth under pressure from your thumb.

7. Always unload canned foods from your car.  Don't allow them to remain in the car overnight during hot weather or during freezing weather.  Whether the can ruptures during freezing weather or not, storing canned food in unheated or uncooled areas costs its lifespan.

8. We will continue to keep canned foods in storage in heated or cooled locations that are dry to ensure their maximum lifespan. Avoid cans which are rusty. They should be stored in areas where rust does not form.

9. Select generic cans carefully.  Some generic cans seem to be made of thinner metal than others.  We can still use generics, but we should select the more substantial cans. Be alert to labels which are stained, indicating leakage from somewhere, perhaps that can, perhaps another.

10. This also impacts something else we do.  When I am able, I donate new canned goods to a food bank, and sometimes to church. Although these are used by church pretty quickly,  I have no idea how long the food banks stock supplies before giving them out.  In future, I will donate only boxes of canned food which comes from Sam's Club which is not only American made, but is known to be very fresh by virtue of rapid turnover and good quality control.

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