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Runajam
07-25-2010, 03:14 PM
I keep reading and hearing wildly different information on shelf life of canned food. How long does it last nutritionally, edibility, etc. Specifically, spam, tomato products, fruits.

eeyore
07-25-2010, 06:30 PM
Try this link it has a lot of info about it. http://www.grandpappy.info/hshelff.htm


Canned Food Study One
A Food and Drug Administration Article about a shelf life test that was conducted on 100-year old canned foods that were retrieved from the Steamboat Bertrand can be read at the following link:

http://web.archive.org/web/20070509153848/http://www.fda.gov/bbs/topics/CONSUMER/CON00043.html

Following is a brief summary of a very small portion of the above article:

"Among the canned food items retrieved from the Bertrand in 1968 were brandied peaches, oysters, plum tomatoes, honey, and mixed vegetables. In 1974, chemists at the National Food Processors Association (NFPA) analyzed the products for bacterial contamination and nutrient value. Although the food had lost its fresh smell and appearance, the NFPA chemists detected no microbial growth and determined that the foods were as safe to eat as they had been when canned more than 100 years earlier. The nutrient values varied depending upon the product and nutrient. NFPA chemists Janet Dudek and Edgar Elkins report that significant amounts of vitamins C and A were lost. But protein levels remained high, and all calcium values 'were comparable to today's products.'"

"NFPA chemists also analyzed a 40-year-old can of corn found in the basement of a home in California. Again, the canning process had kept the corn safe from contaminants and from much nutrient loss. In addition, Dudek says, the kernels looked and smelled like recently canned corn."

"According to a recent study cosponsored by the U.S. Department of Agriculture and NFPA, canned foods provide the same nutritional value as fresh grocery produce and their frozen counterparts when prepared for the table. NFPA researchers compared six vegetables in three forms: home-cooked fresh, warmed canned, and prepared frozen. 'Levels of 13 minerals, eight vitamins, and fiber in the foods were similar,' says Dudek. In fact, in some cases the canned product contained high levels of some vitamins that in fresh produce are destroyed by light or exposure to air."

Kat
07-26-2010, 03:12 PM
I'm assuming that you're referring to wet pack canned goods from the grocery store. If so, the average shelf life as far as I know is considered to be about 2 years. Tomato products used to be one but are now labeled with a 2 year date. This is pretty much the same as home canned goods. There is always a decent chance of something being good long after it's best buy date. As far as dehydrated or freeze dried canned goods go, the average shelf life on any of that is anywhere from 10-20 years+. Grains store the best because of their low moisture content. We have buckets of grain from the late 80s and early 90s that are completely fine and edible still. The biggest difference we saw was the quality of the dehydrated fruits and vegetables when stored over a period of time. It seemed that the more water a fruit or veggie had previous to dehydration, the more fragile they became when stored over time. For instance, a can of broccoli stored for approximately 7 years was crumblier than a can of peas or carrots stored for that same amount of time. We just opened a can of freeze dried diced chicken from 1999 the other day and it was great! It stored beautifully and showed no signs of breakdown. We've also had good luck with dehydrated TVP as well. The only thing I've noticed is that rice takes a little longer to cook, the longer you store it. And I like to season it a bit with bouillon or throw in some bacon TVP for flavor. I usually don't store wet packed goods because of the need to rotate them so often. With the dehydrated and freeze dried foods you don't have to worry so much about rotating them on time which is nice.

Runajam
07-26-2010, 03:37 PM
OK this is what I am talking about. Eeyore is talking about far far longer than two years. I know that what it says on the can cannot be intended for survival purposes. My guess is that it is to move product and have a general guideline more or less to adhere to super stringent Gov regulations. Would that two years be more for ultimate maximum freshness and quality? If I believed a quarter of what the Gov told me....... I'm not looking for best case as far as taste and appearance I'm looking for in an emergency what will keep me alive.

wingfooted
07-26-2010, 04:26 PM
Much depends on storage conditions.

Cool but above freezing is the best. If your storage experiences high temperatures (even 70 F) , shelf life will be cut in half. Freeze / thaw cycling is also bad news. Optimum is a constant 45 - 45 degrees, but above freezing.

Root cellars are probably ideal.

Attics, garages and storage sheds are not good locations for long term food storage.

If you have a situation where your garage or shed is the only place where you can store food, purchase a used chest freezer. A thermostat can be used to control temperature to around 45 degrees. This may not work well if your storage location experiences very cold temperatures during the winter (20F or below for prolonged periods).

Bearman202
07-27-2010, 06:37 AM
A chest freezer works just as well at keeping cold OUT as it does in, doesn't it? I'm thinking that a couple of old freezers that don't work well, but can maintain 45 degrees might be worthwhile. If they can keep the stuff inside from freezing in the winter, and getting above 70 in the summer, I would think they would be close to ideal for someone who doesn't have a root cellar.

1Admin
07-27-2010, 09:16 AM
I'm assuming that you're referring to wet pack canned goods from the grocery store. If so, the average shelf life as far as I know is considered to be about 2 years. Tomato products used to be one but are now labeled with a 2 year date. This is pretty much the same as home canned goods. There is always a decent chance of something being good long after it's best buy date. As far as dehydrated or freeze dried canned goods go, the average shelf life on any of that is anywhere from 10-20 years+. Grains store the best because of their low moisture content. We have buckets of grain from the late 80s and early 90s that are completely fine and edible still. The biggest difference we saw was the quality of the dehydrated fruits and vegetables when stored over a period of time. It seemed that the more water a fruit or veggie had previous to dehydration, the more fragile they became when stored over time. For instance, a can of broccoli stored for approximately 7 years was crumblier than a can of peas or carrots stored for that same amount of time. We just opened a can of freeze dried diced chicken from 1999 the other day and it was great! It stored beautifully and showed no signs of breakdown. We've also had good luck with dehydrated TVP as well. The only thing I've noticed is that rice takes a little longer to cook, the longer you store it. And I like to season it a bit with bouillon or throw in some bacon TVP for flavor. I usually don't store wet packed goods because of the need to rotate them so often. With the dehydrated and freeze dried foods you don't have to worry so much about rotating them on time which is nice.

+1,000

What you'll find is that folks that have been preparing for a while, usually stop messing with standard grocery store wet packed cans after a while and go with dehydrated and freeze dried for real long term storage.

Wet packed grocery store stuff is too much of a hassle to keep up with rotation wise unless your simply looking at a few weeks worth.