Why You Should Never Leave Under Lid Seals On Food After Opening

Whether you believe it will keep your food fresher or are trying to hide the fact that you've already eaten half, leaving the plastic or foil seal under the lid of a container after peeling it back is a common kitchen habit that could give you food poisoning. Leaving the seal on won't add an extra layer of protection between your food and any devious bacteria that may contaminate it. In fact, it has the opposite effect. 

When you leave an open, under-lid seal in place, it becomes another surface that contacts your food and is handled by everyone who opens the container. This creates an opportunity for harmful bacteria to grow, especially if anyone touching the seal doesn't wash their hands first. If someone goes from handling raw meat to opening a container of sour cream to set the condiment bar, a leftover seal becomes just another spot for bacteria like E. coli or even Salmonella. All of these can make anyone in your home or anyone you've served sick. And if you leave the seal on because you believe it keeps your food fresh, rest assured that it already served its purpose.

Containers with under-lid seals are typically flushed with nitrogen before the seal is put in place. The nitrogen gets rid of any contaminants, moisture, and oxygen inside the packaging. The seal preserves this state so that food stays fresh from production all the way to your first bite. Without this process, oxidation can cause nutrient loss, discoloration, odors, and a less-than-appealing taste.

The seal also prevents anything new from entering the container along its production journey. There's a reason product labels often tell consumers not to purchase or consume something if the seal shows signs of being opened. A broken seal could mean any number of safety issues, from tampering to oxidation or other contaminants now inside the container. Since it's nearly impossible to know what could have happened, it's better to skip any containers with compromised packaging.

Once the food has gone safely through the process of creation and packaging all the way to your home, toss the seal once you open a container. Prematurely breaking the seal can cause your grocery haul to spoil more quickly, and reusing the seal can introduce harmful bacteria to your food. Instead, rely on the container's lid to keep your snack protected, and avoid this TikTok hack for storing your food.