You’re cleaning up the pantry, but that means figuring out whether home-canned jars of things are still good. How long is the shelf life of canned foods?
The last thing you want to do is make anyone sick because you cooked something that was expired or had turned rancid. But with the cost of food being what it is, you don’t want to throw away anything that might be salvageable. How long do cans of food last? When it is past its expiration date, does that mean it has turned sour? What signs exhibit when a can of fruit or vegetables becomes rancid? You’ve heard that a bent or damaged cannot be good, but is that true?
Unopened home-canned food product has an average shelf life of 1 to 2 years. Manufactured canned goods last 2 - 5 years and generally have the best quality before expiration. The longevity of canned home items will vary depending on storage and the product's acidity.
While nothing can make a family ill faster than digesting something they shouldn’t, if there’s a chance of saving some of your hard-earned cash by using some items out of the pantry, then you are all for it. What happens when canned foods go bad? What should you look out for? Do some canned foods last longer?
With so many foodborne illnesses floating around, you need to be careful. So, let's dive into the world of mason jars and canning and see if we can’t help you make the most of your pantry without creating more problems than you need.
How Long Do Canned Goods Last?
Depending on the type of canned goods in your pantry, there are some ways of determining the quality of the product inside the can.
Expiration Dates - Commercially Canned Goods
If your panty is filled with commercially canned products, there is usually a date stamp on the bottom of the can. This date is 2 - 5 years from the processing date. The stamped date is a simple estimation of when the product is likely to be at its best. Commercial cans last longer than home-canned products.
While canned foods may be edible after the expiration date, the date is the best guess on the part of the manufacturer for the quality of the contents of the can. Any container that is dented, bulging, cracked, rusted or oozing liquid is evidence of a broken seal and should be discarded immediately. Do not taste or ingest any food from these kinds of damaged containers.
Expiration Dates - Home Canned Goods
If you have any experience with home-canning processes, you have likely been using mason-style canning jars with two-piece metal lids as recommended by the USDA Complete Guide to Canning. To be safe, you have marked the tops of the mason jars with a “made” date. Generally, these products are safe to eat for one to two years from their processing day. Highly acidic foods like jams, jellies, pickles, and fruit, will deteriorate more quickly than low-acids food like vegetables or proteins and are prone to longer shelf lives.
Any pantry, whether canned or home-canned goods, should be used with a “First in, First out” sequence, where the oldest products are used before more recent ones. A monthly check and reshuffling of products in your pantry can help keep the mason jars to ensure that the oldest units are used first.
What Are Some Signs that My Product has Turned?
You should be careful if there is no date on the mason jar lid. An adage says, “when in doubt, throw it out.”
Eating foods from improperly prepared or stored foods that have fermented can produce serious illnesses, such as Botulism. This foodborne toxin attacks the central nervous system, and as it travels through the body, it can produce symptoms like muscle weakness, loss of sight, nausea, diarrhea, and can even be deadly. One of the most common sources of botulism is improperly prepared, stored, or fermented home-canned goods.
- Dark and Cloudy Liquid
- Bubbles in the liquid
- Contents that spew when opened
- Signs of mold growth inside the jar or on the lid (white, green, black, or blue
- Any slimy substance on the top of the food
- Bad odor
- Signs of rust along the lid
- Signs of leakage from the jar or lid
Any jar of home-canned goods that have been stored on the concrete floor of a garage or shed is susceptible to various moistures that can contribute to the deterioration of the product.
Are There Some Things That Can Help Minimize Spoilage?
The number of canning families is increasing daily. According to National Center for Home Food Preservation, there are several things a person can do to keep food spoilage to a minimum.
Remove the Rings After Cooling
Most canning enthusiasts will tell you that the rings on a mason jar are essential for helping create a good seal during the canning process. But, once the jar has cooled completely (12 hours is a good rule of thumb), the ring should be removed. Leaving the ring on the jar just gets in the way of being able to tell if a jar’s lid is losing its sealing properties. By removing the rings, you can spot any leakage that might have remained invisible or hidden by the ring.
Press On The Center of the Lid After Cooling
A light press of the finger in the center of each lid can indicate whether a jar has been set correctly. If the center of the lid pops up after lifting your finger, the jar has not been sealed.
Inspect Each Jar’s lid and Tap with a Spoon
Every jar should have a slight conclave downward in the middle of the lid. Pick up the jar and look across the lid. If you see a slight indentation in the center, you’re good. If not, you don’t have to throw the jar out, just stick it in the fridge and work it into your meal plan in the next couple of days.
Tapping each jar with a spoon can also help you determine if the seal has taken place. A high pitch sound means the seal is secure, while a low thud means not good. Again, just set any unsealed jar aside so you can do something with it.
Wash Each Jar After Sealing
There are times when spillage or microbes from food particles can become attached to exterior surfaces of jars or on top of lids. Washing and wiping each jar can remove and sanitize the jar's glass, so mold and bacteria don’t have a chance to multiply.
Properly Store all Jars
Any home-canned goods should be stored in a dry, dark, cool, safe place away from heat sources, like the hot water tank or furnace. Any jars stored should be kept in rooms 50 to 70 degrees and not stacked more than two rows high.
How Do I Dispose of Spoiled Jars?
If a jar is spoiled, it should be discarded immediately with great care. Botulism can enter the bloodstream by ingesting it directly or contacting the skin. Avoid contact with the suspect foods or the liquids inside the jar, and protective clothing like rubber gloves should be used to protect yourself. Any clothing, surface, or utensil that comes in contact with spoiled substances should be treated with a liquid concentration of one part bleach to 5-6 parts water. Mason Jars that have held spoiled contents should never be reused.
About THE AUTHOR
I have over a decade of experience in food and beverage management, including a ServSafe food safety qualification. As part of this qualification, I have been professionally trained in safe food storage.Read More About Mark Walker