It is a familiar kitchen habit to open a can of beans or corn, use what you need, and slide the rest into the refrigerator in the same metal container. A few days later, the contents can look a little off or pick up a strange smell, which leaves people wondering if they should toss it. Food safety guidance says leftovers from a can can be refrigerated, but that does not mean the can is the best place for them to sit. The bigger issue is quality, meaning flavor, texture, and how well the food holds up once air gets involved.
Guidance cited from the United States Department of Agriculture says unused portions of canned food may be refrigerated in the can, but for best quality the food should be moved to another container. Purdue University Extension also notes that leftovers can be kept for about one to five days depending on what it is. Fish and seafood are on the short end at about two days, while fruit is typically two to four days, and tomato sauce can last up to about five days. Those time windows can sound reassuring, yet they are not a promise that the food will still taste fresh or stay appealing.
Registered Dietitian Nutritionist Kelsey Kunik argues that the simplest upgrade is to transfer leftovers right away into a tightly sealed container. “Personally, I always transfer leftover canned foods to an airtight glass container,” Kunik says, pointing to taste and texture as the biggest winners. Once a can is opened, oxygen starts interacting with both the food and the packaging. That exposure can make delicate flavors fade and can dry out the surface, especially when the can is repeatedly opened and closed over several days.
The metal can itself is not automatically dangerous in the refrigerator, but it is not designed to be a reusable storage box once it is opened. The rim can be messy, and the tall, narrow shape makes it harder to cover securely compared to a flat container with a firm lid. If the can is left uncovered, it can absorb odors from nearby foods, which is how yesterday’s beans can start smelling like onions or leftovers from a takeout box. A sealed glass or food grade plastic container helps block odors and slows down texture changes.
If you do choose to keep the food in the can for a day or two, the key is covering it well and doing it safely. Registered dietitian Kristen Smith recommends a simple solution that most people already have in the kitchen. “Plastic wrap or plastic covers are likely your best bet for covering your food airtight,” Smith says. The goal is to keep air out and keep fridge smells from creeping in, while also preventing anything from accidentally dropping into the can.
Smith also warns against trying to reuse the sharp metal lid that was cut off during opening. “Never try to top the can with the original aluminum can top,” she says, because it can cut your fingers and usually will not seal well anyway. Removing the top completely also makes it easier to press plastic wrap down snugly around the opening. Even with a good cover, the can still is not as protective as a container with a locking lid, so it helps to label the leftovers and use them quickly.
Some foods handle the can better than others, and acidity is the deciding factor. “Non-acidic foods like canned beans, spinach, or tuna generally keep better in the can than acidic foods like tomatoes,” Kunik says. Acidic foods can develop an unpleasant metallic taste faster, especially tomato based products and anything that is strongly vinegar flavored. If you open a can of tomatoes or tomato paste, transferring the remainder immediately can preserve the intended flavor and keep the texture from turning grainy or dull.
People also worry about can linings and chemicals, especially bisphenol A, often called BPA. BPA was used in some can liners, and it has been studied heavily in connection with various health concerns. The United States Food and Drug Administration has stated that BPA used in food containers and packaging remains safe because exposure levels are very low. The Can Manufacturers Institute has also reported that about 98 percent of food cans in the United States are made without BPA linings, which is a major shift compared to years past.
After the main storage decision, the rest comes down to basic refrigerator habits that keep leftovers safer and fresher. Canned food becomes perishable once opened, so it belongs in the refrigerator promptly and should not sit out on a counter for hours. A refrigerator set at 40°F or colder slows bacterial growth and helps leftovers keep their intended taste. Freezing is also an option for many canned foods, and using an airtight container reduces freezer burn and prevents flavors from going flat.
Canning itself is a preservation method that heats food and seals it in an airtight container so microbes cannot grow while it is unopened. Once you break that seal, you are back in the world of normal leftovers, where oxygen, moisture loss, and cross odors all matter. Acidic ingredients like tomatoes can react more noticeably with metal surfaces, which is why the flavor change can feel so sudden even when the food is still within the recommended time window. Think of the can as a temporary package rather than a reusable storage tool, and your leftovers will usually taste closer to what you expected when you opened it.
Have you ever noticed a metallic taste or odd smell from leftovers left in a can, and what storage method works best in your kitchen that you want to share in the comments?
