Powdered milk is one of the best food items to stockpile, as it has relatively a long shelf life and you can use it in a lot of dishes. Although powdered milk does have a long shelf life, but its actual shelf life will mostly depend on how you store it. Provided that you store the powdered milk correctly it can last for decades, on the other hand, if you do not store it correctly it can go bad in a matter of weeks.
You can store powdered milk long term by portioning it into small batches, vacuum sealing the individual batches, and storing it in a cool and dark environment like in a freezer, basement, or pantry. The bag in which the powdered milk has been bought is not ideal for long-term storage, instead, you should vacuum seal it, use mylar bags, #10 cans, or food-grade buckets. If you do not freeze the powdered milk and you store it in food-grade buckets or #10 can make sure to add an oxygen absorber and desiccant in the container.
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The main determining factor for how long the powdered milk will last is what kind of powdered milk is in the container, basically, there are three types of powdered milk and all of them have different shelf lives. The 3 main types of powdered milk are powdered whole milk, powdered buttermilk, and powdered nonfat milk. The main difference between these three types of powdered milk is their fat content.
Generally speaking, fat doesn’t have a long shelf life, and for the most part, food items that do contain fat will have a shorter shelf life. The main reason for this is because fat is fairly unstable and sooner or later it will go bad, this is why a lot of preppers use nonfat powdered milk for long term storage. Powdered whole milk has a shelf life of 2-12 years if stored correctly, powdered buttermilk has a shelf life of around 2-5 years, and powdered nonfat milk has a shelf life of up to 25 years.
You will notice that all powdered milk containers will have a “best by” date which doesn’t necessarily mean that that the powdered milk has gone bad, for the most part, they are still edible even after the “best by” date. Although how you store it will be a lot more important than the expiration date, store it incorrectly and the powdered milk will go rancid in a matter of weeks, it is still edible but it tastes extremely bad. If you want to know how you can store flour long term then check out my recent article How to store flour long term ( In 9 Easy Steps ).
Portion the powdered milk into small batches
Most people who buy powdered milk for long term storage will buy them in 25-pound bags if not in bigger bags. Although you can store the powdered milk in these large bags but it is not ideal. Powdered milk tends to be fairly sensitive to high humidity, temperature fluctuations, and cross-contamination. If you store the powdered milk in a large 25-pound bag and you open it once in a while then you are actually shortening its shelf life.
This is why it is extremely important to portion the powdered milk into small batches, and the size of the batches should depend on how much powdered milk you will use. This way you do not alter the shelf life of an entire batch of a 25 pound powdered milk, and with smaller batches, you can store it a lot more easily. If you want to stockpile food for the long term then you should check out my recent article Survival foods that last forever ( Top 28 ).
Vacuum seal the powdered milk
Once you have divided the powdered milk into small batches, it is a good idea to vacuum seal and store them that way. While you are dividing up the powdered milk into smaller batches you will most likely cross-contaminate it and even add some moisture to the powdered milk. Even if you are extra careful the powdered milk can still absorb some moisture from the air, and having water in the powdered milk will significantly reduce its shelf life.
In addition to this if you do not vacuum seal the powdered milk then bacteria will have an easy time eating away at the powdered milk, as there is plenty of oxygen and humidity in the surrounding air. By vacuum sealing it you eliminate the excess air from the powdered milk and bacteria will not be able to grow as most of them do need oxygen.
Storing the powdered milk in the freezer
If you want to increase the shelf life of the powdered milk then it is a good idea to store it in the freezer. Just keep in mind that it is extremely important to use small batches if you want to freeze the powdered milk, the last thing you want is a 25-pound block of frozen powdered milk. In addition to this, it is also a good idea to vacuum seal the small batches of powdered milk as this way you can use them a lot easier and they will occupy a lot less space.
If you store a lot of powdered milk in your freezer then make sure not to block the air wents of the freezer as this will make the freezer work a lot less efficiently, and it will also use a lot more power, for more information check out my recent article Can a freezer be overloaded ( Top 6 Problems ).
Store the powdered milk in a cool environment
The main factors which determine the shelf life of the powdered milk when it comes to how you store it is the ambient temperature, and the humidity. Ideally, you should store the powdered milk in a dark and cool environment, such as in a basement or in a pantry. Storing the powdered milk in the kitchen is a bad idea, as the temperature fluctuations will be fairly large especially if you often cook.
In addition to storing the powdered milk at a cool temperature, it is also extremely important to store them at a fairly stable temperature. Ideally, you should store the powdered milk in the freezer, although if you open and close the freezer fairly often then you should place the powdered milk at the bottom or the midsection of the freezer, this way you will avoid condensation forming inside the powdered milk due to temperature differences.
Double packing powdered milk
In case you do not want to freeze the powdered milk you should double pack it. If you store the powdered milk in small batches then sooner or later some of them will get damaged, especially if you move them around a lot. In order to prevent any accidental damage to the packaging, you should place the small batches of powdered milk into food grade buckets. Generally speaking, these food grade buckets are fairly sturdy and you can easily move them around without worrying about damaging the bucket.
Before you place the lid on the food grade bucket make sure to place a couple of oxygen and moisture absorbers in the bucket as well. The job of the oxygen absorber is to absorb oxygen and without oxygen, most bacteria and bugs are not able to survive. Moisture absorbers will absorb the water from the air inside the bucket, both oxygen and moisture absorbers will change color once they have expired.
Store the powdered milk in #10 cans
In case you do not want to store the powdered milk in the freezer or in food-grade buckets then you can use #10 cans. These cans are fairly cheap and extremely durable, even if you move the cans from time to time you will not damage them. On the other hand, if you store the powdered milk only in plastic pouches or bags then these will definitely get damaged after some time of usage. Some people vacuum seal the powdered milk and place it in #10 cans with a desiccant and an oxygen absorber, which is a good idea.
Store the powdered milk in mylar bags
In case you do not have a vacuum sealer then you can use mylar bags for the powdered milk, although you will still need to add a desiccant and an oxygen absorber to the mylar bags. Although if you are on a budget you will find that a vacuum sealer is a lot cheaper than buying a couple of mylar bags, although it is still good to know that mylar bags can be used to store powdered milk.
As you can see there are a couple of steps that you should definitely take if you want to store powdered milk for the long term. Even after the expiration date, the powdered milk should be still safe to consume, for the most part, although the more time has passed after the “best by” date the worse it will taste.