We all use flour as a staple in our Western diets, whether all-purpose, whole-wheat, or gluten-free.
All-purpose flour has a long shelf life, but other alternatives can go off within a matter of months. You can prevent this easily by freezing your flour!
Flour doesn’t go moldy like fresh produce, but it can turn rancid (stale and smells off). This usually happens after around 2 years of storage once opened for all-purpose flour.
This happens when the fats are exposed to air and moisture, causing them to oxidize. In warmer climates, flour is also susceptible to developing weevils, small bugs that live in the flour.
Female weevils make their way into the flour package and lay eggs inside the flour grains. The gestation period is between 1 and 5 months. After this time has elapsed the weevils will hatch and move around your flour.
If you see brown granules on the top of your flour, it is likely there are weevil eggs in your flour.
If you are worried, rub some of the brown areas between your fingers. If it emits a minty odor, then you have got weevil eggs in your flour.
If you do not want to do this, an alternative is to tightly pack some flour into a glass and level out the surface. Leave in the sunlight for a few hours. If the surface of the flour appears disrupted, you can assume there have been weevils moving about.
Whole grain flour has a higher fat content due to the entire grain being included. This makes it more susceptible to turning rancid over time. This problem can be avoided by freezing your flour.
You can also store white flour in the freezer to extend the shelf life indefinitely. Whole-grain flour should last around 6 months in the refrigerator or up to a year in the freezer.
Optimal conditions for flour storage are an airtight container, a cool temperature, and darkness.
How to freeze flour
You should never freeze flour in the original packaging. This is because it’s usually made from paper or cardboard, which cannot get wet. This is very likely to happen in the freezer, and so we advise transferring the flour to a different container.
We recommend storing the flour in ziplock freezer bags or an airtight container, labeled with the contents and date frozen. The flour cannot get wet as moisture will cause it to spoil, which is why we recommend these storage options.
You can freeze flour in a large batch or in individual portions. As there is little water content in flour it will not freeze solid. This means that it is easy to remove the quantity of flour required from a larger container.
Some experts recommend freezing your flour for a minimum of 48 hours after purchase to kill any organisms living in the flour.
How to defrost flour
You should allow flour to return to room temperature prior to usage. If you do not do this, the texture of what you are making could be affected.
For example, cold flour could make bread dough very sticky. Some bakers swear by using chilled flour for pastry as they claim it gives a flakier texture.
Factors to consider before freezing flour
Flour is stored in the freezer to kill organisms and bugs living in the product, but also to prevent any entering the flour. This does not mean that flour cannot go off in the freezer, so you should always check the quality before using.
We recommend storing the flour in a large, rigid container. This will take up more space in the freezer but will save on plastic use when opposed to using individual ziplock bags. As flour will not freeze into a solid lump, it will be easy to portion flour straight from the freezer. If you are freezing lots of different flour types, freezing in larger containers will make it easier to organize.
It is important to consider the type of flour you have to ascertain how to store and when to tell it has spoiled. All-purpose flour and other refined flours keep for around 2 years on average. If they have gone rancid, they will smell sour.
Flax, almond, and other nut or seed flours will keep for a year in the freezer. This is where we recommend storing them to keep fresh. This is due to the higher fat content that will cause them to spoil faster. Flaxseed will smell like oil if it has gone off, and should be binned. For other nut and seed flours, look for a bitter and burnt taste to check for spoilage.
Wheat, spelt, and other whole-grain flours go off the fastest of all the flour types. They survive for between 3 and 6 months. These flours should be stored in the fridge and used before the expiration date printed on the package. Look for strange smells to indicate the flour has gone off.
We recommend labeling your flour with the date opened and the expiration date to keep track of how old it is. This will be a good indicator to the lifespan of the flour and how long you have left that the flour is usable.
Flour, particularly refined flour, has a very long natural shelf life.
Whole-grain and other fatty flours should be stored in cool conditions, either in the fridge or freezer. All flours should be stored in airtight containers away from light and moisture.
We recommend freezing flour for 48 hours after purchase to kill off any organisms growing in the flour. You can continue to store flour in the freezer after this point, however, for refined flour, this is not very useful.
If there are weevils in your flour, you do not need to worry. Many people do not like using flour with weevils in, however, they will not cause you any real harm. Storing flour in the freezer slows the rate of oxidation and kills weevils, so don’t worry!