Does wet cat food expire?

Wet or canned cat food often comes in cans or pouches and has a much shorter shelf life than dry kibble. This leads many cat owners to wonder – does wet cat food expire and how can you tell if it has gone bad? Understanding the shelf life of canned cat food and signs of spoilage can help you avoid feeding your cat expired wet food.

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How long does unopened canned cat food last?

Unopened cans of wet cat food will typically last for around 2 years past the “best by” date printed on the can. This is an estimate for optimal quality only – the cans will still be safe to eat for a while after that date. Here are some general guidelines for how long unopened canned cat food lasts past its “best by” date:

Pouches of wet food: Around 18 months

Cans of wet food: Around 2 years
Wet food cans after expiry date: Around 6 months

Keep in mind these are just general estimates – storage conditions like temperature, light exposure, and humidity can affect how long the cans last. Storing them in a cool, dry pantry helps extend their shelf life. Also note that expiration dates are about peak freshness and nutrition content – not safety – so you typically have a grace period after the date before it poses any risk.

Does expired canned cat food go bad?

Yes, like any food, canned wet cat food can spoil after its expiration date passes. How quickly it goes bad depends on factors like:

Ingredients – Cat food with fish tends to spoil faster
Preservatives used

Storage conditions – Heat and humidity speed up spoilage
How long past its expiration date

Even though unopened cans are sealed, the food inside can still degrade in quality and freshness over time. The proteins, fats, and nutrients start to break down. While this spoiled food may not make your cat violently ill right away, it’s best to avoid feeding expired wet food.

What are signs of spoiled canned cat food?

Watch out for these common signs that indicate your unopened canned cat food has spoiled and should be thrown out:

Bulging can – If the can looks swollen or bulging, that indicates bacteria growth inside producing gas. Never feed cat food from a bulging can.
Dents or damage – Severe dents or damage to the can could compromise the seal and allow spoilage.

Discoloration – Look for unnatural colors or a grayish hue.
Mold – You may see fuzzy mold forming on the surface of the food.
Unpleasant smell – Spoiled cat food gives off a rancid, sour, or unpleasant smell when opened.

Change in texture – The food may appear more slimy or gelatinous.

If you notice any of these warning signs upon opening the can, do not feed the food to your cat – it has spoiled and could cause gastrointestinal upset if eaten.

How to tell if opened canned cat food is expired

Once you open a can of wet cat food, it will only stay fresh in the fridge for around 3-5 days. After that, it can spoil quickly. Follow these guidelines for storing opened cans:

Cover the opened can and refrigerate it. This helps slow bacteria growth.
Use an airtight container if transferring to one. Minimize air exposure.
Ideally, use up opened wet food within 5 days.

Smell and inspect before each feeding – discard if you see any signs of spoilage.

The fridge keeps opened wet food fresher for longer, but remember it is still highly perishable and can still expire quickly if left too long. When in doubt, throw it out.

Can you feed expired wet cat food?

It’s generally not recommended to feed your cat canned food that is past its expiration date, even if it’s just a little expired. The risk depends on a few factors:

How long past its expiration – The further past its date, the higher the risk of serious spoilage.
Can condition – Bulging or heavily damaged cans are very high risk.
Storage conditions – Heat and humidity increase spoilage rate.

Preservatives – Some cat foods last slightly longer thanks to added preservatives.
Your cat’s health – Kittens and cats with compromised immune systems are more susceptible to effects of spoiled food.

There is no set rule for how long after the expiration date is still “safe” to feed. To be cautious, throw away wet food even a few months past the date marked on the packaging.

What happens if a cat eats expired wet food?

Eating spoiled, expired canned cat food could cause digestive upset and other health issues in cats. Here are some possible effects:

Nausea/vomiting – Just like humans, consumption of rancid or rotten food can cause nausea and vomiting in cats.
Diarrhea – Loose stools or intestinal upset are common side effects of eating spoiled food.

Loss of appetite – This is common after eating spoiled food as the body tries to avoid it.
Dehydration – Vomiting and diarrhea lead to dehydration as the cat loses fluids.
Weight loss – Decreased appetite and poor nutrient absorption can cause weight loss.

Serious illness – In rare cases, very spoiled food could cause blood infections or kidney failure if bacteria enters the bloodstream.

Keep in mind most cats refuse to eat food that has spoiled – their instinct tells them not to. So serious illness is unlikely unless the cat is forced to eat the expired food. But it’s best not to take risks with their health.

How to store unopened canned cat food

Proper storage is key to extending the shelf life of your cat’s canned food before opening. Here are some tips:

Keep cans in a cool, dry place. Avoid temperature extremes.
Store away from direct sunlight, which speeds spoilage.
Avoid humid storage areas like the basement.

Buy smaller multi-packs instead of bulk cases so food stays fresher.
Keep food in its original packaging until you open it.
Store unopened cans off the floor on a shelf or pallet.

Check expiration dates and use oldest food first.
Wipe off dust and debris from cans before opening.

With proper storage, unopened canned cat food can safely stay fresh for around 2 years past its marked expiration or “best by” date.

What to do with expired canned cat food

If you discover you have cat food cans that have passed their expiration date, here’s what to do:

Inspect each can carefully. Look for any signs of spoilage like bulging, leaking, dents, rust, or odor.
If the cans look fine, you may donate them unopened to a local animal shelter. Most have procedures in place to inspect and safely use donated pet food before feeding.

If the cans show any signs of damage, it’s best to discard them. Place the cans in a bag and dispose in your normal household trash.
Never attempt to return or exchange expired cans at the store. This can spread contamination.
Always discard open cans that are past expiration – do not donate open wet food.

Be sure to replace your cat’s food with a fresh supply so you always have appetizing, nutritious cat food on hand before the old cans expire.

Does refrigerating unopened cans extend shelf life?

Refrigerating unopened cans of cat food can help extend the shelf life slightly by slowing down the natural degradation processes. However, the effect is relatively small. Here’s what to know:

Fridge temp (40°F) only extends shelf life around 5-6 months compared to room temp.

The cold temperature can lead to condensation forming on the cans.
Takes up valuable fridge space better used for perishables.
Increases electricity costs for refrigeration.

Cans take up time to cool down once put in the fridge before benefits start.

Overall, the downsides tend to outweigh the small extension of freshness gained. Leaving cans in a cool pantry is a simpler way to get almost the same effect.

Can freezing unopened cat food extend its expiration date?

Freezing is more effective than refrigerating at stopping the natural breakdown of food over time. However, freezing canned cat food also has some downsides:

Freezing can cause the can to expand and crack.
Thawing and re-freezing repeatedly reduces quality.
Condensation forms on the can when thawing.

Takes up significant freezer space better used for truly perishable human food.
Freezing doesn’t completely stop aging – just slows it down.

Overall, the 2 year shelf life of canned cat food stored properly at room temperature is already quite long. The downsides usually outweigh the small benefit of freezing to prolong it further. Leaving the cans in a cool pantry is the easiest storage approach.

Is it safe to microwave canned cat food?

Microwaving wet cat food that has been refrigerated or frozen is not recommended. The intense heat of the microwave can create hot spots in the food that could burn your cat. There are also some other risks to avoid:

Overheating can break down nutrients in the food.
Metal parts of the can could spark, creating fire hazard.

Can may melt or warp from heat, releasing chemicals.
Microwaving does not reliably kill bacteria and actually could help them spread.

For food safety, it’s advisable to discard any leftover wet cat food rather than trying to re-heat and serve it. Opened wet food also has a very short fridge life before spoiling.

Does protein content affect canned cat food expiration?

Yes, the type of protein and fat sources in wet cat food can impact how long it stays fresh and shelf-stable. Here are some considerations:

Fish – Fish-based formulas tend to spoil fastest.
Poultry – Chicken and turkey formulas have moderate shelf life.

Beef – Cat food with beef often has longest shelf life.
Additives – Preservatives help canned food last longer.

Check ingredient lists for the first 2-3 ingredients. Prioritize land animal proteins like beef over fish for maximum freshness. Also look for natural preservatives like vitamins E and C which can extend shelf life.

Do carbohydrate fillers shorten canned cat food expiration?

Some pet food brands add grain-based fillers like corn, wheat, rice, potatoes, etc to their canned cat foods. This can affect expiration:

Carbs generally last longer than animal proteins when canned.
May slow spoilage of meat ingredients slightly.

Too many carbs reduces protein content, which cats need.
Grain-free wet foods keep quality longer with natural preservatives.

A grain-free wet cat food with meat as the first ingredients and nutritious additives like vitamins E and C offers the best of both worlds – enhanced nutrition and longer shelf life.

How to read expiration codes on cat food cans

Check the key dates stamped on your cat’s canned food cans so you can store and use them while they are still fresh and of high nutritional quality:

“Best by” date – Recommended for peak quality, cans are still fine after.
“Sell by” date – For retailers to rotate stock.

“Use by” date – Last date recommended for use.
Lot number – Identifies production batch.
Digits like MM/DD/YYYY or MM/YYYY – Expiration date.

“Best by” dates are simply recommendations, not safety dates. Cans will stay fresh and usable for a period after that date. Check for bulge, odor, etc rather than just relying on dates.

Conclusion

Understanding how long wet cat food lasts, proper storage methods, signs of spoilage, and decoding expiration dates enables cat owners to maximize the shelf life while avoiding feeding spoiled food. While canned cat food keeps for around 2 years unopened, it’s highly perishable once opened. Use freshness senses like smell along with dates to make smart choices about your cat’s food.