As one of the big staples for baking and providing food, flour is indispensable. But like any other food, if it isn’t stored correctly, it will go bad and become unusable. If you’re storing flour in your pantry and using it regularly, you don’t have to worry about it spoiling.
Storing flour long-term means eliminating, as much as possible, the interaction of the flour with the agents that can ruin it: water, oxygen, and insects. Some solutions allow for more extended storage than others, so your chosen method should line up with how long you plan to store it.
If you plan to change your supplies once a year, you can use a less extreme storage system than if you want your flour to last for ten years or more. Some storage requires electricity, too, so you’ll want to ensure you have access to an uninterrupted source. More on that later.
Why Flour Spoils
Knowing what causes flour to go bad can directly influence how we store it. There are four main culprits, each with its way of degrading flour:
- Odor absorption
Here’s how each of them negatively affects your flour supply.
The boll weevil is the main culprit here, but he’s not the only bug that wants to eat your flour. However, the problem isn’t just that they consume the flour, but that they live in it, which means they, you know, leave stuff behind. Yuck.
So you want to keep them out by sealing off the flour. But since it’s entirely possible that your flour already has eggs in it when you buy it, sealing it from outside bugs becomes superfluous.
Freezing your flour for at least two days after buying it can kill those eggs and prevent the bugs from hatching and ruining your cache.
Mold seeks out just about any moisture it can find, and once it takes hold, it’s pretty hardy. Keeping your flour sealed tightly will prevent humidity from getting to your flour and give mold a chance to gain a foothold.
You’ll know if your flour is moldy, even if you can’t see the mold. Of course, if you notice black spots, you’ll know. However, before you get to see the mold, you’ll be able to smell the telltale sour odor of a mold infestation.
If there are bugs in your flour, you can eat it and still be okay, but that’s not the case with mold, which can be very dangerous to people’s health.
3. Odor Absorption
Another reason to keep your flour in an airtight container is because of flour’s great propensity for absorbing the odors around it. Storing your flour in the paper bag it came from the store in, then placing that bag next to your Vidalia onions means your flour will soon smell like those onions. So will anything you bake with that flour.
As with a bug infestation, you can still consume flour that smells like onions, garlic, or cantaloupe, but it won’t make for the tastiest cookies you’ve ever had.
Perhaps the most insidious threat, oxidation is hard to escape since oxygen is everywhere. Oxidation is why your bag of flour has a sell-by date on it because as the flour remains exposed to oxygen, that element interacts with the oils and fats in the flour.
This interaction causes them to break down, and the oils become rancid. You can still consume this flour, but as the nutrients have broken down, you won’t get any nutritional value, and it will taste bad.
If your flour has a rubbery smell, it’s oxidized past its useful days.
Storing Flour Long Term
We can better store flour for long periods with a working knowledge of these four culprits. One of the key takeaways from the above list is that keeping oxygen away from your flour is your best bet for preserving it.
Storing Flour Up to Six Months
If you’re not storing flour in a prepping capacity but instead keeping it in your kitchen for regular use, you can keep it safe for about six months. Do this by storing it in an airtight container at room temperature.
You can also keep it in the paper bag your grocery store sold it to you in. Unfortunately, if you live in a high-humidity area or have lots of insects, you’re taking a chance on the flour by storing it that way.
I recommend the OXO Good Grips POP Container (available on Amazon.com) since it is airtight and can hold more than four quarts of flour. Its clear plastic is BPA-free, so you won’t have any concerns about keeping foodstuffs inside it.
Storing Floor Up to One Year
Vacuum sealing removes oxygen (as much as possible) from your flour. As a bonus, it makes it a little easier to store your flour since the procedure decreases the bulk of an item by removing air.
The FoodSaver V4840 2-in-1 Vacuum Sealer (available on Amazon.com) offers a couple of options for vacuum sealing and bag sizes, which is important. You want to vacuum-seal the entire bag of flour. If you pour the flour into the vacuum sealer bag, those tiny little pieces of flour will get sucked out with the oxygen, so you need a vacuum sealer that can accommodate larger cargo.
Hearkening back to what we said earlier about bug eggs being present in your flour during purchase, freezing the vacuum-sealed package for two days minimum will kill any larvae inside.
Storing Flour for Five Years or Longer
If you can guarantee a power supply, you can freeze your flour and keep it safe pretty much indefinitely. However, can you guarantee any such thing? Also, if you freeze flour, you must let it return to room temperature before using it. Failure to do so will result in condensation and wet flour is useless to you.
Long-term storage of five years and longer involves airtight containers and oxygen absorbers. Since you’re going to have difficulty finding any container that remains airtight and leak-free forever, you’ll need to use something to eliminate any oxygen that comes calling.
Lining a five-gallon bucket with Premount 14-Mil Mylar Bags (available on Amazon.com) is a good start. There are several sizes in this set, and the 14-mil thickness will help discourage any bag tears that would be catastrophic.
Along with the flour, you’ll want to include an oxygen absorber. These usually use iron powder to initiate a chemical reaction. Oxygen molecules bond with the iron molecules, causing them to rust. As long as there’s unrusted iron in the packets, oxygen will continue getting removed from your storage area.
Consider the Wallaby 300cc Oxygen Absorbers (available on Amazon.com), which come in a 100-count package and are rated safe for food storage.
An airtight container with oxygen absorbers will be your best bet for storing flour for long periods and then (and this is key) having that flour still usable when you break it out.
While flour is vulnerable to a number of elements, oxygen is its biggest enemy. When storing it long-term, keep one word in mind: “airtight.” Even if you’re just keeping flour in your pantry, an airtight container will prolong the lifespan of your flour.