Why will all-purpose flour only keep a few months? Mine is in food grade buckets with oxygen absorbers, no light, low humidity and 68 degrees.
Same question about bleach. Why does it go bad?
I am so glad that you asked this question, as it is one that I frequently get. All-purpose flour is a great staple to have around, but because it has trace amounts of oils from the germ portion of the wheat, the oxidation of oils (when flour is exposed to air) can cause the flour to become rancid over time. The shelf life of all-purpose flour is as followed:
Stored in pantry – 1 year
Stored in refrigerator – 2 years
Stored in freezer – 2 years
The rancidity of the oils present in flour is the very reason why many prefer to store larger amounts of whole wheat berries in their food pantries rather than flour. When you store wheat berries instead of flour, you simple mill the amount of flour you need and store for short-term use.
Flour that does not look or smell good should not be used. If you want flour for long-term storage, it may be best to store whole wheat berries and purchase a grain mill so that you can mill the flour for a fresh source.
The fact that you have made solid headway in giving your stored flour the best storage environment possible will most likely extend the shelf life by several months and prevent oxygen, moisture, sunlight and insect infestations. When you open the container, pour the flour into another airtight container. Or, the original bag can be placed inside of a plastic bag for extra protection. As well, taking the smaller container of flour and placing it in the fridge or freezer can also extend the life.
I hope this helps,