I had 300 lbs of white rice sitting on my kitchen floor, and came to the realization that freezing grains before storage would be a monstrous task in my little fridge. Imagine freezing 300 pounds of white rice, wheat, or beans in a 1/2 freezer-fridge. Thankfully, after doing a little research, I found out that freezing dry staple foods to kill bugs is an outdated method and an unnecessary step if re-packaging foods in oxygen-free storage. (Mylar bags and Oxygen absorbers.) So, don’t do it.
Don’t freeze grain for long-term storage. Freezing is an outdated method of exterminating bugs before long-term food storage. Freezing adds moisture to dry grains, requires excessive freezer space, and takes exponentially more time to accomplish than the preferred method of repackaging into Oxygen-free containers.
People used to freeze grains before storage because most grains (including flour) come with bug eggs. Bugs, eggs, and pupae must be killed before airtight storage, or they will hatch and ruin the batch of food.Scott, Ready Squirrel
When packaging dry staple foods like beans, rice, and wheat in Oxygen-free storage, i.e., using Mylar bags and oxygen absorbers, bugs, eggs, and pupae will be dead within two weeks. Problem solved.
Up next, freezing dry food increases moisture,
Freezing Grain Increases Moisture: Don’t Do It.
When you start prepping for long-term storage, you learn about four things to protect food for maximum shelf-life: moisture, temperature, oxygen, and light. It doesn’t make much sense to freeze food which causes condensation and increases moisture.
Why You Shouldn’t Freeze Grain
Freezing grain causes condensation and increases moisture content during the thawing process. Moisture is the leading cause of grain spoilage after bug damage.
What to do Instead of Freezing
Food-grade containers like Mylar bags that provide an excellent oxygen barrier and the correct # of Oxygen Absorbers are far superior to freezing dry goods for killing bugs within two weeks.
Safety Tip: When dry goods are stored in an Oxygen-free environment, moisture content should be less than 10%. Higher moisture levels are the perfect environment for anaerobic bacteria to form.
Freezing Staple Food Increases the Chance of Botulism
If you read this article, you probably intended to freeze your dry goods and store them in something like Mylar bags, food-grade pales, or glass ball jars.
Grains and other dried foods stored in Oxygen-free containers with more than 10% moisture content create the perfect environment for anaerobic bacteria like botulism to form. This is another reason to avoid freezing grains.
Don’t use a method to kill bugs that add moisture and isn’t 100% effective.
Freezing to Kill Bugs: Is it Effective
The freezing method to kill bug eggs is controversial and is a colossal waste of time. If you want the maximum shelf-life of wheat, white rice, and dried beans, you must repackage them anyway. Freezing is a wasted step, and it’s not great at killing bugs.
Freezing grain to kill bugs, eggs, and pupae is ineffective because there are too many unknown variables. Proper freeze times vary depending on the variety of bugs and the stage of life. Even more confusing, agricultural extensions across the United States disagree on how long to freeze grain.
The most common bug found in wheat is weevils. Different types have more or less resistance to freezing. Imagine a weevil egg on a stock of grain in the frozen winters of North Dakota. The egg goes through winter and hatches in the spring.
When you purchase wheat, it will probably have bug eggs, but you won’t know what variety because weevils travel from one dried food to another. You won’t know if you have a cold-hardy weevil.
For instance, a weevil may be the warm weather variety, easily killed by freezing, or it could be the cold weather type, resistant to freezing temperatures. The stage in a bug’s life cycle: egg, pupae, or mature adult also affects the effectiveness of freezing short-term, say four days.
Imagine freezing 300lb of wheat or white rice in a small refrigerator freezer.
Agricultural extensions from various university extension services suggest freezing times from 4 days to 2 weeks to kill bugs.
Oxygen-free containers kill two birds with one stone. You’ve repackaged into a vessel with a concrete oxygen barrier, and you are killing bugs.
Kill Bugs With An Oxygen-Free Environment: Two Birds With One Stone
If you want grains and beans’ 30+ year shelf life, you must repackage them in oxygen-free containers. Otherwise, you might as well leave them in the store packaging. Freezing is just an extra step.
Store grains like wheat, white rice, and dried beans in a sealed Oxygen-free container like Mylar bags, and food-grade pales, and use an oxygen absorber to kill all bugs, eggs, and pupae within 2 weeks of packing.
Is Freezing Grain To Kill Bugs Practical?
For most preppers, freezing isn’t an option. I look at my freezer full of frozen pizzas, meat, and last year’s Thanksgiving leftovers, and it makes it obvious no way am I freezing 100’s of pounds of dried goods.
Freezing grain to kill bugs isn’t practical. The average household does not have sufficient freezer space to freeze the suggested 300lb of wheat per person. A 50lb bag of grain measures 16″x6″x24. The average dimension of an over-under freezer on a regular refrigerator is 30″ x 35.”
If you are interested in storing wheat berries, but you don’t know which kind to store, check out Best Wheat Berries For Long-Term Storage.
How Long Does It Take To Freeze Grain For Long-term Storage?
As already mentioned, agricultural extensions suggest freezing rice from 4 days to 2 weeks. To keep this simple, let’s say you must freeze your grain for four days.
How long would it take to freeze 300lb of dry goods if you leave them in the freezer for four days?
Let’s say you can fit 10lb of grain in your freezer. How long would it take to treat 300lb for bugs?
It would take 120 days to process 300lb of grain in the freezer. That’s four months of freezer time.
O2 Absorbers or Dry Ice Instead of Freezing: Killing Bugs in Grain
Dry ice can kill bugs in sealed containers, but it has drawbacks. Oxygen absorbers are a superior method and much quicker. Freezing is a wasted step and adds moisture to the dry good.
Oxygen Absorbers are the preferred method for storing dry goods like grains, beans, and white rice. Dry ice is sufficient, but there is a risk of adding moisture to stored food, and it takes longer. Freezing is just an extra step, it kills bugs, but the food needs repackaging for maximum shelf-life.
To treat grain with dry ice, place the dry ice at the bottom of the pale or Mylar bag and wait for 6 hours. If you seal the bag before, the bag may rupture or explode.
To treat bugs with an oxygen absorber, fill the food-grade container with low-fat grain with less than 10% moisture, throw in the proper CC Oxygen absorber and seal the bag. You’re done.