Let’s Talk Flour Storage!

Flour is the universal food of all cultures and the base ingredient in baked goods as well as sauces and tasty food coatings. If you’ve never given any thought how to store flour, this article is for you. Find out about flour containers, flour expiration, if it’s safe to eat expired flour, and the right flour environment.

If you are interested in long-term storage, jump to “How to store flour long term.” To learn about strategies for keeping bugs out of flour, move to “Dealing with bugs in flour.”

Can flour spoil?

Flour can spoil like any other food. Different flours contain different amounts of oil – the oil being the contributing factor that can lead to rancid flour. “Rancid” is the term used for an unpleasant smell associated with decomposing food.

Manufacturers delay the spoilage process by making their product more shelf stable. According to Bob’s Red Mill, the bran and germ are removed during the refinement process to make white flour. Removal of the germ greatly increases the shelf life of white flour, making it the most shelf stable. Other flour types with less processing will spoil more quickly.

Woman unhappy with quality of flour in baking.

Of course, people eat expired flour every day – expiration dates are only suggestions. Consumers can eat expired flour many months and even years past the “best by” date. Two things are important to stress: shelf life varies by storage method and type of flour. Check out spoilage times here.

Flour is safe to eat past the expiration is you have used long-term storage strategies. Consider this scenario: you’re taking an aged, all-purpose bag of flour off your pantry shelf (stored in the paper bag it came from) and want to know if it’s safe to eat. This flour is 2, 3, 4, or (wow) 5 years old. The integrity of the flour is doubtful – throw it out.

If I was taking the flour out of an air-tight container or even better, pulling it from a freezer, (and bug precautions were taken) I have every confidence 2 year old all-purpose flour would still be good to use. Three and four years old? Probably, Five-year-old flour? Yes, if the very best long-term storage methods for flour were used, I would be baking Aunt Mary Lou’s banana bread that same day.

Things get dicier with whole wheat flour and other flour varieties with higher fat content. Refer to “How to keep flour fresh” to learn more about flour storage for these types.

Is expired flour safe to eat? Yes, but it depends on the type of flour and if its properly stored in an airtight container and bug prevention steps have been taken.

Depending on the type of flour and the method of storage, chances are that slightly expired flours are still OK for eating. What you will notice over time is a dip in quality – the flour just doesn’t rise nice like it did before. Baked goods don’t quite have the same delectable texture.

If flour is never opened in the sack it came in, it can go bad. The only actions that will slow down the decay of the flour is storing it in the refrigerator, freezer, or airtight container with oxygen absorber packets.

How do you keep flour fresh?

Flour is freshest when ground directly from wheat berries. After that, the next freshest experience is purchasing ground flour from the store before the “use before date.” Avoid buying extra pounds of flour unless you will use it quickly.

Uncracked grain kernels or “wheat berries” can be stored for years, compared to ground flour. Ground flour loses its nutritional value, compared to unground wheat berries, just because there is more surface area exposed. In addition, fresh-ground grain tastes more flavorful compared with all-purpose bagged flour.

If safety planning and preparedness are on your radar, consider buying a food mill. Store wheat berries and grind whole wheat flour as you need it. Your kids will love the thrill of grinding their own flour and the taste of fresh baked goods.

fresh baked bread

How can you tell if flour is bad?

Signs of bad flour can include change in taste, smell, failure for baked items to rise, and signs of mold. The good news is that most of us never see the ugly side of flour shelf life.

Flour is neutral in taste. A change in flavor or smell doesn’t necessarily mean that the flour has gone bad, because it could have just absorbed odors from “bad actors” stored around the flour as covered in the section, “Where not to store flour.”

An easy way to tell if flour has gone bad is that it doesn’t look like it’s original “healthy” self. This means the original color and texture have changed. Old flour has become darker over time and the texture less smooth.

A slightly sour, musty smell is a sign of mold. In addition, Healthline references the National Library of Medicine by reporting that “gluten-free all-purpose flour, which typically combines several nut- or root-based flours, may be more vulnerable to mold due to its high moisture content.”

It would be easy to see signs of mold in white flour – this would appear as dark or off-color flecks. It is more difficult to see in brown flours, so look carefully for tell-tale signs of mold.

Flour that has gone bad will result in baked goods that will not rise properly.

Hands in fresh flour.

Will I get sick from eating old flour?

The chances of getting sick from old flour are remote. In an article for Women’s Health, Christine Byrne, interviews nutritionist Molly Knauer, RD about flour storage. “If rancid flour contains large amounts of mycotoxins, it can make you sick,” explains Knauer (mycotoxins are toxic compounds produced by certain kinds of mold).”

Never fear, all of your senses kick in around suspicious flour and you will naturally hesitate. The smell of rancid-smelling food or musty-smelling food will discourage you from eating (or at least eating too much). The taste and over-chewy texture tells you something is not right.

You’re probably wondering “what kind of sick?” It is the usual trio of your body reacting to bad gut stuff: upset stomach, vomiting, and/or diarrhea. Again, this is very rare that you would get sick. This should be incentive enough to check the health of your flour!

What happens if I use old flour?

Using old flour will reflect in the loss of quality in your end product. Old flour has degraded gluten, so the dough won’t work up nice when kneading or rise properly. Food made with old flour will have a more chewy texture, but still can be eaten.

At some point, the food will be too unappetizing to eat and should be discarded. However, if you’ve taken proper steps to preserve the flour long-term, loss of quality will be negligible and the baked goods should retain an acceptable level of taste and texture.

OurHalfAcreHomestead proves that old flour bakes up just fine, by making a blueberry cake with 7 year old whole wheat flour! Wow! In another video, the host demonstrates how she cans flour (I’ve embedded at the end of this article). She says that old flour will be hard and lumpy. No worries, she gently digs it out of the jar and throws it in the food processor. The flour returns to it’s fluffy self.

In another video, a baker demonstrates making baguettes with 5-year-old flour! He compares baking with fresh versus flour that has been stored long-term. Fast forward to minute 9:30 to see him removing the bread from the oven and comparing quality between the baguettes. In his opinion, the 5-year-old bread tastes pretty good.

How to dispose of old or bug-infested flour

The best way to dispose of old flour is to put it back where it came from – out in nature. Dispose of old flour by sprinkling it in with green plant compost and mixing thoroughly. Regardless of disposal method, there are considerations to pay attention to:

  • do not dispose of old flour where pets or wild animals can eat it and get sick or where it would attract wild animals to a house
  • for bug infestations, minimize handling time inside the house to reduce spread of bugs
  • do not dispose of flour in an indoor trash can, bug infestations can spread to the house
  • dispose small amounts of old flour down a garbage disposal with adequate water so as not to clog drains

Which flour lasts the longest?

Shelf life is impacted by:

  • ingredients
  • level of processing
  • storage methods

Making biscuits with flour.

Different types of flour have varying shelf lives. Whole-grain flour (such as oat, spelt, rice, and whole wheat flour) and gluten-free flour (such as cornmeal, almond flour, and buckwheat flour) have shorter shelf lives than white flour (such as all-purpose flour, bread flour, or self-rising flour). Whole grain flour tends to contain more natural oils, which spoil quickly. White flour will last 6-8 months at room temperature, depending on the surrounding temperatures. Whole grain flour will last 3-6 months at room temperature.

Below is a chart of expected shelf-life of flour based on storage approach. Extended long-term storage requires special steps and equipment to hit the longer shelf times. Some of them are pretty neat, jump to the end of this article to learn about long-term storage options for flour.

Flour shelf life by method


 Cool place



Vacuum Sealed Bags

Mylar bags+ Oxygen Absorbers+

Food-grade buckets 

All Purpose

6-8 months

1 year

2 years

1-2 years

5-20+ years

Whole Wheat

3-6 months

6-8 months

2 years

1-2 years

5-20+ years

Flour containers challenges

There are many options and ways to store flour. Flour does best stored in an airtight container away from sunlight. Both sunlight and air speed up the natural decay of flour. The other primary goal of flour storage is to keep bugs out.

A University of Minnesota Extension bulletin extensively covers pantry pests, “Pantry pests: Insects found in stored food.” To say the least, it was disturbing. Folks, you must get your flour storage right! If you’re bringing the paper bag of flour  home and putting it in a cupboard or open shelf, you are at risk for attracting bugs.

In the article “Dealing With Bugs in Flour” step 1 is to freeze the flour for at least 4 days to kill the bugs already in your flour. If you choose to store the flour at room temperature, then you have two choices:

  • airtight containers
  • preparing the flour for long-term storage

Use our chart of perfect flour container chart to find 2-lb, 5-lb, and 10-lb airtight canisters, plus bucket size.

In the warmer climate of the southern United States, fighting pantry moths is more of a daily battle. In the midwest, I have kept an everyday flour canister on my countertop that is not airtight. The more I learn about bug infestations and preventing them, the more I am a proponent of airtight flour storage.

Paper flour storage

flour in paper bags

Flour is sold in paper bags so moisture can escape to prevent mold from developing.

From there, the flour should be transferred to bug-proof containers or put directly into a freezer or refrigerator.

For long-term storage, plan on transferring the flour into bug and moisture-proof containers stored in ideal conditions for flour storage.

Flour sack storage

The image of cloth flour sacks brings back the romantic idea of flour storage of yesteryear. Charming vintage flour sacks were the original “upcycled” product, being used to make flour sack dresses, flour sack towels, and other articles for the home.

Cloth flour storage is not in use today simply because it isn’t the best storage for flour. Although the cloth did successfully allow flour to “breathe”, it isn’t the best bug barrier.

This doesn’t stop you from buying flour sack towels for your kitchen – which are still a superb way to dry dishes and super-cute for your kitchen decor.

The right location and environment for flour storage

Flour stores the best in dry, cool environments with minimal temperature fluctuations. Any moisture can lead to mold growth. Flour will last the longest in the absence of air. Oxidation occurs when oxygen from the air interacts with nutrients in the flour, causing them to break down.

To store flour long term and to extend the shelf life of flour, freeze flour. For freezer storage, store flour in an airtight container or a resealable freezer bag, after pressing out all of the air (a vacuum seal bag is ideal). The freezer will kill off any pests that might grow in the flour.

  • store flour in an airtight container to prevent an increase of moisture
  • store airtight, flour containers away from sunlight and in dark spaces
  • to extend shelf life, store airtight flour containers in refrigerators or freezers

According to MasterClass, “If you keep flour in a cold place, let the cold flour come to room temperature before you use it; otherwise, it won’t rise. Only defrost what you need, if you keep defrosting and refreezing flour, it will go bad.”

Now, you are probably thinking, “oh, I will just put the mylar food bag in the freezer and it will last forever!” There is one problem to that scenario, oxygen absorbers don’t work well (or at all) frozen and using a freezer/oxygen pack combo is just redundant. Using the mylar bags in the freezer without the oxygen pack would work, but why pay for such expensive freezer bags?

Mylar is a valuable tool to your long-term food storage because it doesn’t depend on electricity and doesn’t use up your freezer space. It’s very important to diversify your long-term food storage methods.

“Only take the amount of flour you will use from a freezer or refrigerator and don’t re-chill or refreeze it. This will degrade the flour for future use.”

There is an art to handling flour when it comes out of the freezer. Flour should be allowed to come to room temperature and remain sealed so condensation stays on the outside of the container and doesn’t get to the flour. Condensation is the enemy of flour and can result in a breeding ground for mold.

It’s interesting that the Primal Survivor goes as far as giving details for drying damp flour:

“If the flour gets damp, you can spread it out on a baking sheet and heat it in the oven at about 200F.  If the flour is very damp, you might need to heat for up to an hour to get it dry.  After drying it, sift it to remove any clumps.”

Where not to store flour

Flour is a somewhat neutral tasting food, but it will absorb odors around it. Storing next to laundry detergent, strong-smelling food (like onions), and chemicals will permanently alter the taste. Take it from me, your cookies will taste like soap.

Keep flour away from strong odors like garlic, onions, detergent, and cleaners.

The best way to guarantee taste is not tainted is to store the flour in an airtight container. Sunny locations are a no-no because sun degrades flour, especially if it is stored in glass containers on a counter. Some purists will only use glass containers. They feel that plastic can also emit odors that flour can absorb.

Avoid storing flour containers in kitchen cabinets next to heat-producing appliances. This includes stoves and refrigerators. Storing next to other neutral foods in the pantry is a good ideas.

How to store flour long-term for storage/ emergency food supply

I think all of us can manage preserving flour for up to two years simply by dropping it in the freezer. There are pantry and preparedness enthusiasts out there who have pushed long term food storage past that. I’ll cover them and a few techniques below.

Worth mentioning here is the Church of Latter Days Saints (LDS)/Mormons. Many people are not familiar that one united goal of this religious sect is preparedness. Because of the emphasis on long-term food storage, members have perfected tools, equipment, and methods for preparedness. For example, they publish “Longer Term Food Storage” as a guide anyone can benefit from. Emergency preparedness is an admirable goal everyone should strive for.

Online survival. preparedness forums contain much chatter around long-term food storage. Experienced preppers can offer helpful advice. Most of the time, mylar bags, food-grade buckets, and oxygen absorbers come up.

Canned flour. Yes, you can can flour. In the video above, OurHalfAcreHomestead demonstrates how to can flour. She reports that she has stored canned flour successfully for 4 years, with no degradation in the white flour. In another video, she demonstrates using 7-year-old flour to bake a blueberry cake. The sealing process of the canning keeps the air out, preserving the flour long term.


Disclaimer: this method may not meet food preservation standards with the oven canning technique. NEVER can low-acid products food like meat and vegetables using the oven canning method. It is dangerous because it doesn’t reach high enough temperatures to properly preserve food and prevent deadly botulism poisoning. -Penn State Extension

Mylar bags. If you want to store flour long-term (think a decade!), then the best method is Mylar bags with oxygen absorbers.  No other method is truly reliable for long-term flour storage. These bags will shield your flour from any light, moisture, or oxygen, making it last as long as possible.

Food-grade buckets. These buckets have lids with airtight seals and work in tandem with oxygen absorbers. For a 1-2 punch, store the mylar bags inside of the food-grade buckets – the buckets are a good barrier to insects and rodents.

Oxygen absorbers. These packets remove oxygen from sealed containers. Any potential insect eggs cannot hatch due to the absence of oxygen.

In conclusion

Thanks for hanging out with me and learning about flour storage! I hope you are inspired to take better care of your flour so it can serve you better!

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