How to Store Flour for Prepping: The Complete Guide

Flour, due to its variety of uses, has long been considered a pantry staple. For this reason, it should also be part of your long-term food storage plan in any prepping strategy. The question is, how do you store flour properly for the long-term?

To store flour for prepping, you need to store it in a way that avoids moisture, oxidization, and insect infestations. It can be stored for periods of 1 to 15 years and beyond. Flour made only with the endosperm of the grain instead of the whole-grain tends to offer longer storage times.

This guide will provide you with the information that you need to store flour for the long-term. It will provide you with details on what makes flour go bad, the best types of flour for long-term storage, and the best storage methods so that you can apply the best flour storage solution for your needs.

What Makes Flour Go Bad?

Flour, being a dry powder resulting from the grinding of grains, does not spoil in the sense that other moisture-rich foods do. However, if you have ever opened an old bag of flour from your pantry and noticed a moldy or rancid aroma, you know that flour is not immune from spoilage.

As a prepper, spoilage is a dirty word. It is something to be avoided or at least minimized. To combat spoilage in your long-term flour storage you need to be aware of the three main causes of flour going bad in order to mitigate their effects.

Moisture

If you store your flour in a high humidity environment or in an area that suffers from frequent temperature variations, the stored flour will be prone to absorb moisture. Unfortunately, it will not dissipate it as quickly. This results in the flour becoming susceptible to mold growth.

Moldy flour is detectable by the musty or acidic odor that it produces. It can also become discolored, taking on a tan or yellowish appearance. When used, it can result in food with unpleasant flavors. Additionally, it can also expose you to the risk of mycotoxins. It is a byproduct of mold interacting with the flour that can cause adverse health effects if consumed.

The moisture retention properties of flour also make it susceptible to absorbing the smell of other foods stored nearby. This is why flour needs to be stored in a dry and cool location with as little temperature fluctuations as possible.

Oxidation

Oxidation is the process by which oxygen in the air interacts with the flour molecules. The flour production process, in part, relies on oxidation. It helps to give flour its color and enhances its properties when turned into a dough.

However, prolonged oxidation is what can make flour rancid. This occurs when oxidation begins to breakdown the nutrients in the flour, primarily the natural oils. Since these oils are found in greater abundance in the germ and bran of grains, whole-grain flours are more susceptible to this type of rancidity than white flour. The latter being made from the endosperm of the grain with little to no germ or bran.

Insect Infestation

Insects in your food is a subject that is cringy to think about. However, when it comes to flour, the reality is that it can be more common than you would like to think. Even under normal usage, a bag of flour meant for daily/frequent use in your cupboard can be prone to insect infestation.

Since long-term flour storage involves having flour for years, not just weeks, the potential for insect infestation is increased.

The root of most insect infestations in flour starts before you purchase the flour. Grains are susceptible to infestation from weevils and other pests before they are ground into flour. Even after the flour is packaged, most flour is packaged in paper bags that offer a weak barrier to other pests once the flour is in transit or at the store.

Most flour pests lay their eggs in the kernel of the grain and can take months to hatch. This is one way that bugs can get into your flour before you open the bag. As such, any long-term storage method for flour needs to assume that pest elimination needs to occur before the flour is stored and shield it from infestation while in storage.

What Type of Flour Is Best for Long-Term Storage?

The United States Department of Agriculture classifies flour as a shelf-stable food. This means that it can be stored safely at room temperature. However, as has been presented above, ambient conditions concerning moisture, oxidation, and insects can greatly reduce the actual shelf-life of flour.

Different types of flours will have different shelf lives, be it for short-term or long-term storage.

Refined Flours

Refined flours are all of those produced from wheat grains that use only the endosperm of the grain. This reduces the natural oils and lowers the onset of rancidity.

Refined flours include:

In the first three refined flours on the list, the main difference is how finely they are milled. Bread flour is the coarsest, cake flour the finest, the more finely milled the grain, the lower its protein content. The higher the protein count, the more glutinous the dough made with the flour will be.

While the coarseness of the flour affects its end-usage, it does not offer any added benefit or detraction in using it as a determining factor in improving long-term shelf-life.

Self-rising flour contains a leavening agent, usually baking powder. While the addition of baking powder does not impact the storage life of this type of refined flour, the leavening effect might be reduced over time. This means that with long-term storage, self-rising flour will remain viable, but you may lose the self-rising effect when baking with it.

When you consider the attributes of each of the refined flours, selecting all-purpose flour as your flour of choice for long-term storage makes sense. First, it tends to be the most economical and readily available. Second, it provides you with a full range of usage in a survival situation.

Recommended: Can You Eat Wild Rye?

Whole-Grain Flours

Whole-grain flours are those that use the whole grain, the bran, germ, and endosperm. These can be made from wheat as well as buckwheat, amaranth, rye, and oats.

Even though there is a nutritional benefit in storing whole-grain flour in a prepper’s pantry, primarily its higher content of iron, vitamin E, thiamin, folate, and other nutrients, white flour is preferred for the reduced risk of rancidity.

Even so, for those who wish to store whole-grain flour for the long-term, it is possible. The methods listed below will clearly state which are apt for whole-grain flours.

Flour Packaged for Long-Term Storage

There is flour that is commercialized specifically for long-term storage. Augason Farms Enriched Unbleached All-Purpose Flour is an example of this. These flours are usually canned or vacuum-sealed and contain food-grade oxygen absorbers. This allows them to have a shelf-life of 15 to 25 years when stored unopened in a cool and dry environment.

While this ready-made solution facilitates the process of storing flour, it is important to take into account that such solutions will be costlier compared to storing your own flour. Also, such solutions may not always be readily available, especially during times of impending crisis.

Flour packaged for long-term use has its place in a prepping strategy. For example, when you need to bolster your food stockpile and time to do it yourself is at a premium.

It can also be an acceptable choice when your survival plan is meant to cover just yourself. It can also be an effective bridge between when you start implementing a food storage plan and handling the individual food storage tasks yourself.

However, knowing how to properly store a staple item such as flour on your own is an essential skill for prepping. Taking the ready-made solution compromises your opportunity to develop hands-on survival skills for convenience.

Best Options for Storing Flour

There are several methods for storing flour for the long-term. All tackle the dreaded risk factors that make flour go bad: moisture, oxidation, and pest infestation. In terms of shelf-life, this will vary with the method.

Preparing the Flour for Storage

One thing that all flour storage methods share in common is that you must start preparing the flour for long-term storage.

Removing Flour From Its Original Packaging

Unless the flour was packaged specifically for long-term storage, flour should never be stored for the long-term in its original packaging. This is because flour is normally sold in small paper bags at the retail level. Even at the wholesale level, flour is commonly sold in sacks that are permeable, easily allowing in air and ambient moisture.

Large containers sold to bakeries and industrial kitchens can come in a variety of packaging, including large drums. However, while more resistant than retail packaging, these are still not sufficiently resistant for long-term storage. Additionally, once opened, the entire supply of flour within the container becomes exposed.

When storing flour for the long-term, you need to procure airtight containers. These can be made of any food-safe material like glass, plastic, metal. The individual containers that you select for storing the flour should be sized to have the capacity for the amount of flour that you plan on using for a set period.

If you live in a dry and temperate climate, it is recommended that each container store no more than 90 days of your anticipated use of flour. If you live in a humid climate, it is recommended that your containers store no more than a 30 days supply of flour. This is to minimize the amount of flour that could be wasted due to spoilage or rancidity.

Ensuring the Flour Is Dry

Before storing the flour using the storage method of your choice, you need to make sure that it is dry. If you are experienced in handling flour, a visual inspection should suffice. However, if you are uncertain or suspect that the flour is damp, you can apply one of the following drying techniques.

Dry Flour in the Oven

Spread it thinly over a cookie sheet or other flat baking pan, not more than ½-inch (12.5 cm) thick.
Place the pan in an oven at 200℉ (93℃).
Stir the flour with a fork every 10–15 minutes.
Monitor the flour each time you stir it.
If it no longer displays signs of dampness, remove the pan from the oven.
Allow it to cool off in a cool and dry location.
Avoid keeping the flour in the oven for more than one continuous hour.

You want to avoid burning your flour when using this method of drying. At this temperature, it will slowly begin to yellow and turn to a dark tan if left in the oven too long after it has reached peak dryness. If this happens, it is still usable. However, it may impart a nutty flavor to it.

Drying flour in the oven works best for refined flours. Whole-grain flours could experience issues in terms of flavor and consistency when made into a dough when oven-dried. There is a variation to this method of ensuring that your flour is dry and friendlier to whole-grain flour. It is described in detail below in the dry canning method.

Air Drying Flour

This method should only be used if the air is consistently dry where you intend to dry the flour. A relative humidity level in the 30 to 45 percent is best for this method. The flour should not be visibly damp. It is the simplest method. All that is required is to place the flour on cooking sheets and leave them uncovered for 12–24 hours.

Be advised that if the relative humidity is higher than the range mentioned above, air drying flour would be ineffective and possibly counterproductive.

Sifting After Drying

Once you have dried your flour using one of the methods above or simply transferring the flour from its original packaging, if it is in a sufficiently dry state, the flour should be sifted before moving on to the next step. This helps to remove clumps.

Minimizing the Risk of Insect Infestation

If you chose the oven method of drying your flour, that step alone should have killed any residual insect eggs and larvae that the flour may have had. If you chose air drying or skipped additional drying altogether, the flour should be placed in an airtight container and placed in the freezer for 48 hours.

Even if you chose the oven method of drying, placing the flour in the freezer once it has cooled is a good way to ensure that residual pests and their eggs are killed, thus preventing an infestation once stored for the long-term.

Methods for Storing Flour

Once you have put your flour through the drying and insect mitigation steps, the packaging and storing process comes next.

Vacuum Sealing

This method requires using food-grade vacuum seal bags and a vacuum sealing machine, such as the GERYON Vacuum Sealer Machine.

Since pouring flour directly into the bags would result in the flour being sucked into the vacuum tube when activated, you need to either return the flour to its original bag or, preferably, into clean paper bags.

The paper bags filled with flour would then be placed inside the vacuum food bags, then emptied of air and sealed using the vacuum sealing machine.

This will give refined flour a shelf life of two to three years; whole-grain flours one to two years.

Using Oxygen Absorbers

Another method to store flour is to use dry airtight containers. Preferably, containers with a sealing gasket, such as mason jars.

You place the flour in the container and add an oxygen absorbing packet rated for food-use in the jar before closing it tightly. The packet will absorb oxygen and extend the shelf-life of refined flour to five to seven years. Whole-grain flour stored in this manner can last two to three years.

Storing in Mylar Bags

Mylar bags, such as Outus Mylar Food Storage Bags, are food storage bags that are impervious to moisture and oxygen. Whether you vacuum seal them, opt for regular heat sealing or sealing with a hot iron, a highly resistant barrier between the flour and the elements is made.

If you add oxygen-absorbing packets before sealing the mylar bags, you have essentially created the best possible environment for storing flour in the long-term.

This method will give refined flour a shelf-life of 15 years or more. This also happens to be the storage option that gives whole-grain the longest shelf-life possible of 10–12 years.

Freezing Flour

Theoretically, freezing refined flour will make it last indefinitely and allow whole-grain flour 15+ years of shelf-life. However, whenever freezing is mentioned as a food storage strategy, it needs to be measured against its practicality in a survival situation.

Freezing requires electricity to run the freezer. If you do not have a sustainable power source to keep the freezer functioning during momentary or prolonged power outages, your frozen flour stores could be jeopardized.

This is why, as effective as it is, it cannot be recommended as your primary storage method if you are planning on a serious prepping strategy. It is best to use freezing as a secondary method of storing flour, with your primary store relying on one of the other methods described here.

Dry Canning

Dry canning involves using canning jars in the oven as opposed to a hot water bath. When dealing with whole-grain flours, using canning jars to dry them instead of the direct oven method can help preserve their viability after storage.

You preheat the oven to 200℉ (93℃).
Fill each jar with flour until you reach half an inch (1.25 cm) from the rim.
Place your filled jars on a baking sheet and place them in the oven.
Leave the jars in the oven for one hour.
Place the lids on the jars upon removing them from the oven. Screw the lid tightly over the band.
When the lids pop, move them to a cool place to assume room temperature.
Once cooled, move the jars to a cool and dark storage area.

There are some issues voiced by food handling experts regarding dry canning regarding food preservation. However, these issues focus on foods that have an inherent moisture content above ten percent. In the case of flour, its moisture content is well below this. Even so, to avoid any risk of contaminating your flour or making it dangerous to use, you may want to avoid dry canning.

Conclusion

Storing flour for the long-term is an essential skill required to maximize your food storage capability. By knowing how much moisture, oxidation, and pests can jeopardize the integrity of flour while in storage, you will be able to minimize the impact of those factors and prolong the shelf life of flour.