Can you leave food in the can after opening?

It is undeniable that cans are the packaging that best preserves food, but is it safe to leave these products in the can once it has been opened?This is a very common question, as we often don’t consume all the contents of the cans and don’t want to throw the food away.

So, in this article we will understand whether or not it is possible to leave food in an open can, and what risks this practice can cause.

Index of this article:

  • The role of cans in food preservation
  • Is it safe to leave open cans in the fridge?
  • Risks of leaving food in an open can
  • How to store canned foods safely?

The role of cans in food preservation

The can is a container that prevents the entry of air and microorganisms, preventing contamination.

Cans are excellent packaging for preserving food, and they are containers that guarantee a long storage time, without the need for refrigeration.

However, for the food to be well preserved, the can must be intact. In other words, it must be closed and without dents.

This occurs because the can, despite being made of metal, has an internal protective layer, like a varnish, which prevents the metal from coming into contact with the food. Furthermore, the can, when sealed, prevents the entry of air and microorganisms, thus preventing contamination.


But, once opened, the can loses its ability to preserve food, and becomes an unsuitable container, even when placed in the refrigerator.

Is it safe to leave open cans in the fridge?

As stated above, an open can is an unsuitable container for storing food, as it loses its sealing capacity.

This means that it allows the entry of air, contaminants and microorganisms, which accelerate the degradation of food.

And even in the refrigerator, which is an ideal appliance for storing perishable foods, the products inside the can are at risk of contamination.

This occurs because there is air circulation inside the refrigerator, which comes into contact with everything stored there.

Risks of leaving food in an open can

We already know that it is not safe to store food in open cans, whether in the refrigerator or outside.

So, now let’s understand these risks better:

  1. Risk of contamination

The main risk of leaving food in the can after opening is contamination by microorganisms, especially fungi and bacteria .

Thus, in addition to spoiling food, these organisms can cause infections and very unpleasant symptoms, such as:

  • Diarrhea
  • Nausea
  • Vomiting
  • Abdominal pain
  • Generalized malaise
  • Fever

Additionally, children and older people can be more severely affected by foodborne infections, sometimes requiring hospital admissions.

  1. Chemical contamination

Once opened, the internal protective layer of the can is broken, which can cause the metal to come into contact with the food.

Therefore, as most cans are made of aluminum, food contamination by this metal may occur.

  1. Changing the taste and smell of food

As the open can can no longer prevent air from entering, the food stored there may undergo some changes, whether in taste or smell.

This occurs more intensely when the opened can is stored in the refrigerator, where air circulation is more restricted.

How to store canned foods safely?

The ideal is to consume canned food at once, but you can transfer leftovers to other suitable containers.

After opening a can, the ideal is to use all of its contents.But, as this is not always possible, you can store leftovers of these foods in other containers, which are more suitable for preserving them.

However, these containers must have lids that close tightly to prevent air from entering. Furthermore, these leftovers should be stored in the refrigerator, to reduce the chance of bacteria and fungi proliferating.


by Abdullah Sam
I’m a teacher, researcher and writer. I write about study subjects to improve the learning of college and university students. I write top Quality study notes Mostly, Tech, Games, Education, And Solutions/Tips and Tricks. I am a person who helps students to acquire knowledge, competence or virtue.

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