You can keep the corn kernels to make popcorn in their original packaging at room temperature for about two years. Once prepared, popcorn should be stored in an airtight container at room temperature for 1 or 2 weeks, as you should avoid the fridge.
If you want to learn how to preserve popcorn properly, keep reading.
How to store popcorn kernels or flake to make popcorn
Regardless of if the kernels are designed to prepare popcorn in the pan, pot, or microwave, you must keep them inside an airtight container.
If you keep the sealed package, put it inside an airtight container. Then, place it away from direct heat or sunlight in a dark, cool, and dry location, such as the cupboard or pantry.
Once open, the strategy is the same. Transfer the content to an airtight container (preferably glass) and store it in a place with the abovementioned conditions.
The sealed corn kernels remain in good condition for two years. Once open, you will be able to store popcorn kernels for a year. 
Store popcorn at room temperature
To preserve popcorn at room temperature, you should do the following:
- Step 1: Avoid dressing popcorn.
After preparing the popcorn, do not salt them all, much less add butter, caramel, or any other dressing you like to use with popcorn. (Also check these post about how to store peanut butter or how to store liquid or solid caramel)
First, set aside the amount you plan to save, and then proceed with dressing to your liking the popcorn you will eat.
- Step 2: Wait for the popcorn to cool completely.
Spread the popcorn on a tray so that they cool much faster.
- Step 3: Transfer the popcorn to an airtight container.
After they are cold, pour the popcorn into the airtight container (made of plastic, glass, or metal). The important thing is that the lid seals well and prevents airflow.
You can also use ziplock bags, but containers provide better protection, especially against insects that can poke holes in the bags.
Another tip is to cover the top of the container with plastic wrap, seal the container with the plastic, and then place the lid on top to reduce air intake.
- Step 4: Write down the storage date.
Write the storage date or paste a label with the date.
- Step 5: Store in a dry and dark place.
Put the popcorn in a place that does not have moisture and where it does not hit the heat or light directly, and you will be able to store popcorn for one or two weeks at room temperature.
If you seasoned the popcorn, you could follow the same directions, but they will last much less. Those with salt or some other seasoning may last between 3 and 4 days.
While those with butter, caramel, or chocolate on top, as well as popcorn you made in the microwave, may last 1 or 2 days at room temperature.
You should not store popcorn in the refrigerator, as the fridge’s cold accelerates the decay process and promotes the appearance of mold.
Can you freeze popcorn?
Although it is not a highly recommended option, it is possible, so avoid it as much as possible. However, it is a method to extend the shelf life of popcorn.
To freeze popcorn, you need to carry out the following steps:
- Step 1: Do not season it.
Adding salt, butter, caramel, or any other dressing to the popcorn you will store is not advisable.
- Step 2: Wait for them to cool.
Spread the popcorn on a tray so that it cools evenly and much faster.
- Step 3: Store the popcorn inside an airtight bag.
Put the cold popcorn in an airtight, freeze-safe bag. But if you have a vacuum sealing machine, it could also work.
- Step 4: Label it.
Write the storage date of the popcorn on the bag or stick a label with the date.
- Step 5: Store in the freezer.
If you follow these tips, you may freeze popcorn for about three months. Since popcorn does not freeze, you can take it out of the freezer and eat it without “thawing.”
But if you want, you can bake them for a few minutes; you just have to spread them on a tray so that they heat evenly.
How to preserve popcorn that comes prepared and bagged?
You can also get store-bought popcorn, which usually comes in plastic bags like Cheetos and is primarily sweet (caramelized). Although they also come salted or buttered.
These sealed popcorn bags keep well until the expiration date indicated by the manufacturer. You must store them in dry places, which are dark and cool.
Once open, store the remaining content in an airtight container or bag in a dry, dark, and cool place for a week.
How do you know if the popcorn got bad?
First, to determine if the popcorn kernels got terrible, you must check them; those with cracks or holes will not burst or become popcorn, as they lost the internal water they should have, losing the property to retain the steam inside them, which causes the “explosion.”
In the case of popcorn as such, if they change the flavor and become bitter, it means that they have already spoiled. The same with those that smell bad or have black or greenish spots because it means that mold has developed.
Why does popcorn spoil?
Popcorn spoils from the natural decomposition process in any food, which accelerates if you do not store popcorn in optimal conditions.
That is, they are exposed to moisture, which in turn causes the appearance and development of mold, bacteria that are harmful for consumption.
Or they are exposed to light or direct heat, which accelerates the growth of decaying bacteria.
These bacteria make them smell rotten or vile and then finish decomposing them, making the popcorn sticky, or hardened.
In the case of corn kernels, they decompose when they dry and break. If they are not well stored, the small amount of water they have causes them to dry out and eventually break.
In addition, corn kernels attract many insects, so if they are not well covered, there is a chance you will find them infected with insects, which will gradually eat the grains.
How long does popcorn last?
|Corn kernels at room temperature (sealed)||2 years|
|Corn kernels at room temperature (open)||1 year|
|Popcorn at room temperature (no additives)||1 – 2 weeks|
|Popcorn at room temperature (with salt or seasoned)||4 – 5 days|
|Popcorn at room temperature (butter, caramel, chocolate, or some other dressing)||1 – 2 days|
|Microwave made popcorn at room temperature||1 – 2 days|
|Frozen popcorn||3 months|
|Store-bough popcorn at room temperature (sealed)||Until the expiration date|
|Store-bough popcorn at room temperature (open)||1 week|
What is the best way to store popcorn?
The best way to preserve popcorn is to store it in an airtight container at room temperature where direct light does not hit, away from devices that emit heat, and in a dry place.
In the same way, if kept sealed inside an airtight container, corn kernels will last quite a long time.
Refrigeration is not a good option for popcorn or corn kernels. And freezing is only an option for ready-made popcorn because the beans can crack.
If you are interested in this kind of information, this website has hundreds of topics about food preservation that you might like.