Does almond flour go bad?
In this short article, we will answer the question “Does almond flour go bad?” We will also talk about the shelf life of almond flour as well as the best ways of storing it.
Does almond flour go bad?
Yes, almond flour goes bad, particularly if stored improperly. There are several ways in which almond flour can spoil, including fat degradation, insect infestation, and mold growth
Almond flour is a fine powder made from ground unpeeled almond nuts, which contain about 50% of oil in its composition.
Hence, almond flour is high in fat, as shown in a study conducted by Yildiz and Gocmen , who reported a fat value of 57%.
For comparison purposes, white wheat flour contains 1% fat, whole wheat 2.5%, and rice flour only 0.5% fat [1,2].
The fat content in almond flour is primarily unsaturated. According to research , about 90% of the fat in almonds is monounsaturated and polyunsaturated.
Due to this high content of unsaturated fat, almond flour is highly susceptible to becoming rancid.
Rancidity is the result of a chain of reactions that can take place when unsaturated fat degrades due to endogenous enzyme activity or to contact with air, yielding off-flavors and off-odors.
Light and heat may boost oxidation reactions, therefore, protecting the almond flour from these environmental factors helps extend the shelf life of this product with regard to fat degradation.
Almond flour quality may be also substantially reduced if the product is subjected to insect damage during storage, and moisture pickup from the surroundings, which can favor clustering.
As a general rule, the low moisture content of almond flour (3%) inhibits the development of bacteria. However, certain species of fungi may still be present, as shown in a study performed by Lanza and others .
Hence, the absorption of moisture could also encourage fungal growth and eventually favor the growth of bacteria .
As stated by Lanza and others , some mold species can produce toxic compounds known as mycotoxins, making flour unsuitable for consumption.
What Is the Shelf Life of Almond Flour?
Almond flour can last for a few months (6-12 months) in the pantry or refrigerator, provided it is stored properly.
Based on fat oxidation markers, Raisi and others  found that ground almonds stored at ambient temperature (23°C) and in contact with the air remained fresh for 6 months.
Under airtight conditions, the authors were able to extend the shelf life to more than 10 months.
Many almond flour manufacturers recommend refrigerating the product, particularly after opening the package.
In the same study, Raisi  observed that under refrigeration (4°C), ground almonds remained fresh for more than 10 months, in the presence and absence of air.
Thus, the shelf life of your almond flour will strongly depend on the ambient storage conditions, lasting for 6 months to 1 year. For an exact shelf life, stick to the date printed on labels.
What are the signs that almond flour has gone bad?
Due to the high content of unsaturated fat, fat oxidation is the main spoiling reaction taking place in almond flour. Rancidity can be easily noticed by unpleasant rancid odors and tastes.
Oxidized almond flour will probably make you reject it. Also, be aware that using oxidized almond flour in recipes can ruin them due to the off-flavors that rancid flour can bring to the product. So the wise thing to do is to discard it.
Mold growth is also a possibility, and can be identified by bluish-green spots on the powder. If any signs of mold are detected, it is recommended to discard the flour as certain mold species can produce toxic compounds .
If you detect clustering, this indicates that the almond flour absorbed moisture from the environment. It is not safe to consume flour like this because the higher moisture could have favored microorganisms’ growth .
You should also look for bugs or flour worms if the item is contaminated. Nut flours attract specific insects, and even though the product is still useful, the appearance of bugs signals that it’s time to throw it out.
How to Keep Almond Flour Fresh?
Keep your almond flour stored in a clean, cool, dry, and dark place, in an airtight package or container. Remember that almond flour is rich in unsaturated fat, which is prone to oxidation.
As fat oxidation reactions occur in oxygen-rich environments and are accelerated by light (such as sunlight) and heat, keeping the flour away from these factors will help keep its quality longer.
Considering oxidation markers, Raisi and others  showed that ground almonds stored under airtight conditions remained fresh for longer (>10 months) than ground almonds exposed to air (6 months).
Chilling your flour, notably after it has been opened, extends freshness because chilling reduces the rates at which chemical reactions (such as fat oxidation) and microbial growth occur .
For this reason, many manufacturers advise refrigerating almond flour.
Raisi and colleagues  concluded that refrigeration (4°C) is necessary for preserving the freshness of almond flour for a longer duration, as compared to storing it at room temperature (23°C).
They also inferred that almonds exposed to air at ambient temperature (23°C) were the least stable compared to those kept refrigerated or protected from oxygen.
Flour, in general, is extremely sensitive to moisture. If any moisture gets into the almond flour, it becomes clumpy at best and soon moldy. It’s critical to keep your flour well-sealed from the weather.
Is it necessary to keep almond flour refrigerated?
Although refrigeration can extend the shelf life of almond flour, as already demonstrated in previous research , it does not need to be refrigerated to be safe.
Chilling can help your flour keep fresh longer, but if you store it properly in the pantry or other adequate spot, it will be safe and of good quality until the stated best-before date.
Proper storing conditions include keeping almond flour away from moisture, heat, light, and air contact.
In this short article, we provided an answer to the question “Does almond flour go bad? We also talked about the shelf life of almond flour as well as the best ways of storing it.
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