How Long Can You Leave Wet Cat Food Out Before It Spoils?

As any cat owner knows, the portion of wet cat food is almost never just right. Sometimes, the can or pouch is not enough for the hungry hungry kitty, but more often than not, you're left with some of the wet cat food. Throwing it away seems wasteful, so the next logical question is "How long can you leave the wet cat food out before it spoils"?

The short answer is 1-2 hours (according to the FDA), but let's go a bit deeper and find out why you shouldn't leave wet cat food out more than that, what can happen if you do, and what you can do to safely store the cat food.

How long can wet cat food sit out?

The 2-Hour Window

According to the FDA, perishable food left at room temperature for more than 2 hours should be thrown away.  Some cat food brands advise keeping wet food out for a maximum of 1 hour, while other brands instruct that it is safe to keep their wet food products out for as long as 4 hours.

Please note that these timelines are more of a guideline than a rule. Depending on the type of wet food you've just opened, how fresh it was, and the temperature in the room you leave it in, it might take 1 hour or less for it to go bad, or it might be perfectly good to serve after 4 hours. Here are a few things to keep in mind:

• Always check the expiration date on the can or pouch of wet food. Do not feed your cat expired wet food. However, if the expiration date is coming up soon, then remember that it might take less time for the food to go bad if you leave it out (that's closer to 1 hour rather than 4).
• Never leave the wet cat food in direct sunlight because this will make it go bad much quicker. If the opened can of wet food has been in the sun on a hot summer day for more than half an hour, you should probably consider throwing it away.
• The ingredients in the wet food have a major influence on how long it can last out. For instance, fish-based wet food will go bad quicker than chicken-based cat food. Additionally, organic wet food for cats does not have chemical preservatives, which makes it spoil quicker than commercial brands of cat food.

Readers Favorite Cat Food and Covers:

• Best Canned Cat Food
• 3 DIY Homemade Cat Food
• Pet Food Covers

What Happens When Food Goes Bad?

Feeding your cat wet food that has been out for too long is dangerous because it is a very good medium for the development of bacteria and fungi. As the food begins to spoil, the chemical composition of the ingredients changes, and it becomes a good breeding ground for these pathogens.

Let's take an example. When you leave food out for a day or more, you will find it riddled with mildew. This is the massive development of fungi in the spoiled food medium. This is a fortunate situation because mildew is visible. When you see it on the food, you know that it's no longer good to eat.

It usually takes about 24 hours for mildew to develop (maybe less during summer), but it takes far less for bacteria to develop on the wet food that's going bad. As the pathogens develop, they consume the nutrients in the food, thus altering the chemical composition, and they produce toxins that stay in the food.

When you feed your cat wet food that's been out for a long time, you are also feeding it the bacteria and the toxins that it has produced. Depending on the type of pathogen that has developed, the cat may start feeling ill and you might see some of the following symptoms:

• lethargy
• fever
• diarrhea - the severity varies a lot depending on the pathogen
• blood in the stool
• nausea
• vomiting
• loss of appetite

If you notice these symptoms in your cat, you have to take it to the vet because it needs medical attention. Diarrhea is dangerous because the cat becomes dehydrated  easily. Moreover, the nausea and vomiting prevent the cat from drinking water to rehydrate, so it might need to be hydrated subcutaneously/intravenously.

Aside from dehydration, infectious gastroenteritis will not go away on its own. The cat will need antibiotics to fight off the bacteria that is developing in its digestive tract. It will also need a special diet to help it throughout the treatment.

Is it Worth Leaving Wet Cat Food Out?

While that's ultimately up for you to decide, when you leave wet cat food out, even in the 1-4 hour window, the food starts to go bad. After about one hour, the meat begins to dry out, which means that there is little chance that your cat will eat it.

The sauce also gets a darker colored pellicle on the surface, which makes it less tasty. The smell is not the same and the taste is most likely not the same either after it's been out for a few hours. All things considered, wet cat food that's been out will probably not be a tasty or healthy meal for your cat.

So what can you do? When you're left with half or one-third of a can of wet cat food, are you supposed to throw it away?

The answer is no, there are plenty of solutions that prevent spoilage, as well as waste. Here are some of the best ones:

What You Can Do to Prevent Spoilage and Food Waste

1. Refrigerate It

By far the best solution of all is to refrigerate wet cat food. You should do this as soon as possible after opening it to prevent the development of pathogens. You can keep the cat food in the fridge for maximum  2 days, but make sure to check the label for specific instructions. Some cat food products might spoil quicker than others. Ideally, the leftover cat food that you store in the fridge should be served for the cat's next meal.

When you serve the cat food, always make sure that you do not serve it cold because it can make your cat ill. If it eats the food cold, right out of the fridge, it could get laryngitis or pharyngitis. This could be a simple sore throat or a more complex inflammation that requires treatment. To avoid this, leave the can out until it gets to room temperature or heat it up.

Keep in mind though that heating up cat food in the microwave is not a good idea because it does not heat up evenly and it can have certain areas where the temperature of the food is very high. A good way to heat it up is to add a bit of warm water or low sodium chicken stock and stir to warm up the food. If your kitty does not show the same interest for the second serving of the wet cat food, then check out our 5 ways to spice up cat food.

2. Buy the Smallest Cans/Pouches

Wet cat food comes in containers of many shapes and sizes. Each cat has its own eating habits. While some cats eat a standard pouch in a single serving, others might eat it in as many as three. Choose which wet cat food you buy depending on how much your kitty usually eats in a single meal. While smaller cans and pouches are usually more expensive than larger ones, consider it an investment in your cat's wellbeing. Feeding your cat fresh food each time is the ideal approach.

3. Use Can Covers or Ziploc Bags for the Fridge

When you store wet cat food in the fridge, you have to cover it to keep it fresh. If you don't cover it, then it will dry out and you will have to throw out a large portion of it on the second serving. Moreover, it is important that the wet cat food gets as little air as possible, even in the fridge.  

While refrigeration slows down the alteration process significantly, having access to air still permits the development of some bacteria and fungi. So when you store the cans in the fridge, use a can cover to keep the food safe and to prevent it from drying out. Pet food can covers are inexpensive and extremely useful. As an alternative to pet food covers, you can use Ziploc bags. Simply place the can inside the Ziploc bag, get the air out, and zip it up to keep the food safe.

If you have leftover cat food in a pouch, then you can use a food seal clip and then place it in a fridge. If you don't have any, then Ziploc bags are also very useful for pouches. Another alternative is to take out the leftover cat food and move it into a plastic container with a lid.

To sum up, wet cat food can be left out for up to 2 hours, but do this only if you have no other alternative. Your best choice is to get your cat smaller portions so that you don't have any leftover cat food. If you do have leftovers, though, you should refrigerate it after opening the can/pouch. Use a pet food can cover for the cans you refrigerate to store it safely, then remember to heat up the food before you serve it.

How do you store your leftover cat food? Does your cat enjoy it on the second serving? Tell us all about it in the comments section below.