Canned Food Shelf Life – Off Grid Living Smart


Everyone has been in a situation where you throw out that can of green beans just because it’s a week past its “best by” date”. Why chance eating something that could make you sick? If the label says it’s past its prime then It’s expired. Right? Canned food expiration dates serve as a guideline to help you rotate your usage of these products. In this article learn how to know if the canned goods on your shelf are still safe to consume years past the expiration date.

Proof of a Long Shelf Life

In 1865, a steamboat loaded with canned provisions left port for the mining camps in Montana. Unfortunately, it had too many provisions and the weight of the vessel caused it to sink early on in its journey. It sat at the bottom of the Missouri River for nearly a century. Among the provisions were cans of plum tomatoes, mixed vegetables, peaches, oysters, and honey.

In 1974, several scientists at the NFPA checked the content of the cans. They found that the products still had significant nutritional value and zero microbial growth. In fact, the chemists found that these canned goods were just as safe to eat in 1974 as they were to eat 100 years earlier.

“Best By” Dates

You must learn how to tell the difference between canned foods that safe to consume and those that are not. There are too many variables outside a food manufacturer’s control to come up with a reliable expiration date science.

best by-cans

The 2 main variables that affect canned food’s storage shelf life are:

1 – Temperature exposure

Extremely high temperatures will compromise most foods. Unless you are turning grapes into raisins or actually cooking your food for consumption, you don’t want to store canned goods in high heat environments.

What’s worse is large temperature variations. Food left in high temperatures, then low temperatures, and then back to high temperatures, its shelf life will be compromised.

Unheated, uninsulated garages or attics are terrible storage locations.

2 – Can integrity

The second variable to watch out for is can damage. If a can was dropped, crushed, or dented in any way then the integrity of the can comes into question. Damaged cans may have seal issues.

If a can is damaged then the odds go up significantly of air penetrating the can. Organic matter (food) exposed to air will tend to mold. Moldy food is bad and can make you sick.

Of these two variables, the food manufacturer can only really control the second one. And only before it ships. Once it’s shipped from the canning factory, they no longer control this variable either.

For instance:

  • A forklift could puncture the can during loading.

  • Shifting pallets often crush the cans on trailers in traffic.

These are variables that food manufacturers have no way to control. A clue that canned food shelf life dates are arbitrary is that they now don’t even say “Expiration Date”.

Nowadays the majority of canned food stamps “Best By” or “Best If Used By” labels on them.

Of course, fresher food is always better. No one is arguing that fact. However, not being “best” and not being consumable are very different things.


Best Canned Goods Storage Tips

To prolong your canned food shelf life, focus on good canned food storage techniques. Keeping any food fresh past their typical shelf life depends on the conditions in which you keep these emergency food items stored.

1. To begin with, never buy the dented cans.


Sure, many people say there’s no issue to buy cans with dents. This is true if consumed quickly but if you’re stockpiling food goods, a dented can is a liability. Don’t settle for cans or jars lids that have even minor damage. Cans with damage will lead to premature bacterial growth over time. This is often more important than the expiration dates label.

2. Canned food shelf life can be significantly affected by moisture.

You want to control the humidity in your storage environment. Dry foods can pick up moisture that can lead to mold and bacterial growth. Moisture can also lead to the breakdown of packaging containers, such as aluminum or tin cans. As these containers oxidize and rust, they can affect canned food shelf life.

3. Mid-range temperatures are best to improve canned goods’ shelf life.

Shoot for temperatures ranging from about 40 to 70 degrees Fahrenheit.

A study conducted by Brigham Young on wheat over the long term showed that wheat kept in cool storage, such as a basement, would be edible for years. Wheat stored in a hot environment such as an attic would only be acceptable for consumption for five years. On the flip side, canned food shelf life can be significantly decreased if items become frozen even if just for a short period.

4. The shelf life of canned food can also be negatively affected by direct sunlight.

While you may enjoy laying in the sun and baking, your canned goods won’t take very kindly to this process. The heat from direct sunlight will speed up the deterioration of the cans and the contents as well.

The Expiration Dates?

Canned food expiration dates serve to let you know which products last longer than others. Using them simply as a reference can be helpful, as long as they are not taken too seriously.

You will not die if your green beans are a month or even a year past their expiration date if you are storing your canned goods properly to ensure that these foods last as long as possible.


But how do you know if the canned goods on your shelf are still safe to consume years past the expiration date?

The following are some signs that the food in those cans may become contaminated:

1. Don’t just look at the expiration dates on canned food.

Look at the cans themselves. Do they have dents, rust, or are they bulging?

These are signs that the food items contained in them have become compromised.

Also, the shelf life of canned food can be compromised in jars that have signs of corrosion on the lid and liquid seeping under the lid of the jar. You should discard jars with this appearance.

2. The nose really does know.

Bad smell is a helpful indicator of rotten food. So if you’re uncertain about the shelf life of canned soup, for instance, simply open it up and take a big whiff.

A bad odor will serve as a good indicator and will let you know in most cases if the contents of the can are bad.

3. A few more signs to look out for.

Discoloration. Although by itself this might not be anything to fear, with any other signs of contamination present, it’s best to discard this food. Importantly, don’t consume eggs that float in water. Also, any can or jar that spurts liquid upon opening is a good sign that the food is bad. Mold is another indicator that the food has spoiled.


It is important to realize that the dates on canned goods simply don’t matter. What really matters is what is in the can. If you store canned goods in ideal conditions and take good care of it, they can live well past the expiration on the can.

So when you ask yourself, “what is the shelf life of canned food?” Keep in mind that the food is fine to eat for years to come. Using some basic common sense tips can go a long way in helping to feed your family through the tough times.

If you have concerns about the quality of the contents of a can of food you are about to consume then err on the side of caution. But don’t hesitate to use your five senses to assess the shelf life of canned food. This is a better way to tell if canned foods are still safe to eat than any arbitrary date printed on the packaging.