I’ve been researching the best way to store wheat flour long-term. One common method, said to be “best”, is to freeze the flour. Any food kept at zero degrees F will keep indefinitely. That’s good to know. But I have 50 lbs of flour and a small amount of freezer space. So I’m going to have to define “best” as including factors like cost and practicality.
There are various pieces of advice that survivalists and preppers give concerning flour storage. One of the top recommendations for storage longevity is cool temperature:
“For every 10°F increase in temperature, the shelf life is reduced by almost 50 percent.” (Food Storage for the Clueless, Clark L. and Kathryn H. Kidd, 1999, p. 271).
This assertion is well-documented. It’s not a prepper myth. So keeping food in a cool location, e.g. a 60 degree basement, can double shelf-life versus a 70 degree closet.
However, the typical basement is damp, and moisture is worse than temperature in causing food to go bad. Flour is particularly susceptible to moisture, because it has a high surface area. So flour needs to be kept in a well-sealed container. I use a 5-lb bucket with a Gamma Seal lid. For moisture absorption, I use salt instead of silica gel. I pour a whole container of table sale (26 oz) into the bottom of the bucket. Then I place the flour on top (in their original paper package). Salt will absorb about 6% of its weight in water. So those 26 oz of salt will absorb just over 1.5 ounces of water.
Wheat berries are sometimes recommended for long-term storage over flour. There is a claim among some preppers that the berries keep much better than the flour. But I think that depends on the storage conditions. Whole wheat berries contain oils in the bran, which go rancid from oxidation of the lipids after a number of months. White flour has very little oil, since the bran has been removed. So on that score, white flour is better. On the other hand, the berries have much less surface area, which is also a factor in oxidation. In any case, to make bread from the berries, you would have to grind your own flour. That is too time-consuming for me, and I prefer white flour. (Store what you eat, I say.)
Oxidation of any food can be reduced in a number of ways, so as to increase the shelf-life of the food.
Oxygen absorbers are available from our advertiser. Use one or two per 5 or 6 gallon bucket. This method is commonly used by preppers, and it works well.
But oxidation occurs more readily in the presence of moisture, so you should also use silica gel packets or salt in the buckets. If the food is in packages, you can put salt in the bottom of the bucket. If the food is loose (beans, rice, wheat berries), then you are probably better off with the silica gel. Or you could seal the salt in a paper envelope, and place it on top of the food. The less moisture you have, the lower the oxidation rate (except for fats, which are not affected by moisture levels).
Another way to reduce oxidation is by keeping the food cool. Oxidation is a chemical reaction, and temperature slows the reaction. So these three factors — cooler storage temperature, less moisture, and of course less oxygen — all reduce oxidation and prolong food storage times.
How long will the above methods work to keep flour fresh in storage? It is uncertain. I read varying reports from preppers on their experiences with flour storage. Some claim that flour keeps up to 5 years; other say 1 or 2 years. So I would suggest that the above methods be combined with a food rotation schedule. We use about 5 lbs of flour a month (for about 4 loaves of bread). So my 50 lbs of flour will complete one rotation in about 10 months. All your stored foods will be fresher and more palatable if you use a rotation schedule. But this implies that you are storing mainly the foods that you eat on a regular basis.
In addition, if you need water purification equipment, there is a new product on the market, from one of our advertisers, called LifeStraw Family. Click the LifeStraw ad near the top of the right column, but then look for the “LifeStraw Family” link. It’s under $90 (as of this writing) and will purify thousands of gallons of water. The “Family” version is better than the “Personal” version (which actually looks like a fat straw) because the Family version filters out viruses as well as bacteria and protozoa. I think it’s the least expensive water filter that removes all pathogens to EPA standards.