Properly Storing Opened Cans of Cat Food
Keeping your cat’s food fresh and safe is a top priority for any cat owner. Once a can of wet cat food is opened, it becomes vulnerable to bacteria growth and nutrient degradation. Properly storing open cans helps preserve the taste, texture, and nutritional value of the food. It also prevents foodborne illnesses that can arise from eating spoiled cat food.
When deciding how to store an opened can of wet cat food, there are a few key factors to consider. This includes storage time, refrigeration method, signs of spoilage, and ways to prevent waste. Following proper storage guidelines will ensure your cat’s mealtime is always safe and enjoyable.
Food Safety Risks
Once an opened can of cat food is exposed to air, bacteria can begin to grow rapidly and contaminate the food. The moist environment of wet cat food provides an ideal breeding ground for dangerous pathogens like Salmonella, Listeria, E. coli, and Clostridium botulinum, the bacteria that causes botulism (https://thecatsite.com/c/how-long-can-you-safely-keep-cat-food-out-for/). These bacteria multiply exponentially between 40°F and 140°F. Refrigerating or freezing opened cans prevents this bacterial growth and keeps your cat’s food safe.
In addition to bacteria, mold can also grow on exposed cat food. Molds produce toxic byproducts called mycotoxins that can make cats sick. Refrigeration inhibits mold growth by lowering the temperature and moisture content of the cat food.
Chemical changes can also occur in cat food over time, especially when exposed to air and light. Fats can oxidize and proteins can denature, leading to rancidity, off-flavors, and loss of nutrients. Refrigeration slows these chemical reactions and deterioration.
Nutritional Value
The nutritional value of wet cat food can deteriorate over time after opening the can, especially if it is not stored properly. According to Tufts University’s veterinary nutritionists, the vitamins in wet food are vulnerable to destruction when exposed to air and light1. Vitamins like thiamine, vitamin E, and vitamin A degrade quickly once the can is opened. Refrigeration can slow this nutrient loss. Cornell University experts also note that the fats in wet cat food can oxidize after opening, leading to rancidity2. Oxidation causes the fat molecules to break down and can create free radicals that are harmful if consumed. Again, prompt refrigeration after opening will help minimize oxidation and preserve the nutritional content.
That said, wet cat food that is promptly refrigerated and consumed within a few days retains much of its original nutritional value. As long as good storage practices are followed, wet food still provides higher protein, moisture, and fat content compared to dry kibble. Refrigerating open cans prevents drastic nutrient degradation.
Taste and Texture
Leaving canned cat food out at room temperature can cause it to spoil much more quickly, negatively impacting the taste and texture. According to Tufts Vet Nutrition[1], the fats in wet cat food can turn rancid after prolonged exposure to air and warmer temperatures. Fat rancidity leads to unpleasant tastes and smells that cats will likely reject. Additionally, the gravy in canned cat food can turn gelatinous when subject to higher heat and humidity, altering the mouthfeel that cats expect from their food[2]. Refrigerating an opened can prevents these undesirable changes in taste and texture by protecting the vulnerable fats, proteins, and fluids. So for the best flavor and mouthfeel, cat owners are advised to promptly refrigerate any unfinished canned food.
[1] https://vetnutrition.tufts.edu/2020/10/the-scoop-on-storing-pet-food/
[2] https://www.snappytom.com/post/what-makes-canned-cat-food-spoil
Storage Time Recommendations
The USDA recommends only leaving wet cat food out at room temperature for 1-2 hours before refrigerating or discarding it[1]. Once opened, wet cat food should be transferred to an airtight container, refrigerated, and used within 3-5 days for the best quality[2].
Pet food companies like Hill’s Pet Nutrition also advise refrigerating opened wet cat food cans. They recommend using refrigerated wet cat food within 5-7 days and keeping it covered in the fridge[1]. This helps retain moisture, minimizes air exposure, and reduces bacterial growth.
Proper Refrigeration
Proper refrigeration is crucial for preserving the safety and quality of open canned cat food. As soon as you open a can of cat food, it is important to transfer any unused portion to a sealed container and place it in the refrigerator immediately (1). The ideal temperature range for refrigerating open canned cat food is between 40-45°F (1). At this temperature range, bacteria growth is slowed considerably.
Make sure to cover the can or storage container tightly before refrigerating (2). An airtight seal helps prevent moisture loss and keeps out contaminants. Leaving the can uncovered in the fridge can lead to the food drying out or absorbing odors from other foods. Some experts recommend transferring the cat food to a clean, dedicated container just for pet food to avoid any issues (3).
Properly refrigerating open canned cat food right after opening helps maintain safety and optimal nutrition for the duration of storage.
Signs it’s Gone Bad
There are several clear signs that indicate your canned cat food has spoiled and is no longer safe to feed your cat. According to Hepper, the main signs to look out for include:
Mold. The appearance of mold, fuzz, or spots on wet or dry food means it has spoiled and should be discarded immediately. Mold spores can cause illness if ingested. Check cans carefully for any punctures, rust, or bulging lids that may allow moisture in and mold to grow.
Smell. A rancid, sour, or unusual smell means the food is past its prime. Snappy Tom notes a rotten or spoiled smell is a telltale sign canned food has gone bad. Trust your nose – if it smells off, don’t feed it.
Discoloration. A change from the normal color or unnatural hues may signal spoilage. Look for fading, darkening, or unnatural colors. Quora mentions a color change in dry food as a sign of staleness.
Texture changes. If the consistency is overly soft, slimy, sticky, or hard and dried out, that indicates spoilage. The texture should match what is expected for that variety.
Serving Tips
When taking portions of refrigerated, open cat food out to serve, it’s important to follow proper procedures to avoid contamination and food waste. Here are some tips for serving refrigerated open cat food safely:
Transfer small portions to a separate container or dish when taking it out of the fridge. Scoop out just what you need for one meal instead of bringing the whole container to your cat’s bowl. This helps prevent introducing bacteria from your cat’s mouth into the refrigerated portion. As noted on the Hill’s Pet Nutrition website, “Transferring a portion at a time prevents the remaining food from repeated exposure to air and introduction of bacteria from your pet’s mouth” [1].
Avoid letting any utensils that touched your cat’s mouth go back into the refrigerated cat food. Always use a clean spoon each time you scoop food out. Wash utensils thoroughly with soap and hot water after each use. This practice helps avoid cross-contamination.
Do not return any unused portion back into the refrigerator after serving. It is safest to discard any leftover wet food once it has been transferred out of refrigeration and into your cat’s bowl. As Hill’s notes, “Once exposed to air and your pet’s saliva, leftover or unused portions cannot be safely refrigerated or frozen” [1]. Fresh portions should always be taken for each meal.
Other Storage Options
In addition to refrigerating open cans of cat food, pet owners have some other options for safely storing and feeding wet food to cats:
Freezing
Some pet owners choose to freeze single servings of wet cat food in an ice cube tray or small containers. This helps the food stay fresh longer, allows for portion control when feeding, and makes thawed portions easy to warm up. Pet owners recommend labeling frozen portions with the date and contents. Thaw portions in the refrigerator overnight before feeding.
According to The Spruce Pets, frozen wet cat food will maintain quality and nutrition for around 6 months.
Self-Feeding Systems
Automatic cat feeders designed for wet food allow you to store larger amounts while keeping portions fresh. These systems often have an ice pack to help keep food chilled and rotated bowls to serve timed meals. The equipment can be helpful for pet owners who have variable schedules.
Canning
Some pet owners opt to can and sterilize their own homemade cat food to control ingredients and safely store larger batches. However, home canning cat food can be labor-intensive, requires following canning best practices, and may not provide a complete nutritional profile without the guidance of a veterinary nutritionist.
Conclusion
As we’ve discussed, proper refrigeration of open cans of cat food is crucial to maintaining its freshness and nutritional value, as well as preventing foodborne illness in cats. Leaving wet cat food out at room temperature for more than 2 hours enables dangerous bacteria like salmonella to multiply quickly. Refrigerating open cans prevents bacterial growth by slowing down the spoilage process. It also helps retain the taste, texture, and vitamin content of the cat food. Storing open cans in the fridge for no more than 3-5 days is ideal. After that, any uneaten portions should be discarded.
Pay close attention to any changes in smell, appearance, or texture, as those are signs the food has likely spoiled and become unsafe to feed your cat. Always keep refrigerated cans of cat food in sealed containers or zip top bags, and make sure your fridge is below 40°F. By properly refrigerating open cans, you can maintain the quality of the cat food and avoid gastrointestinal upset or illness in your beloved feline companion.
