January 23, 2014, by Ken Jorgustin
The shelf life of your food storage is affected by many things, perhaps most important are temperature, moisture, atmosphere, and containment.
Here’s more detail
Temperature greatly affects food storage life.
USDA guidelines say each 10°F drop in temperature doubles the storage life (relatively). Similarly each 10°F rise will halve the food storage shelf life.
Having said that, read this regarding use-by and sell-by dates.
An example of the general relationship of food storage shelf life with temperature:
Generally, food shelf life is referenced to room temperature – which we’ll say is 70°F.
80°F (0.5 the stated shelf life)
90°F (0.25 the stated shelf life)
100°F (0.125 the stated shelf life)
60°F (2.0 the stated shelf life)
50°F (4.0 the stated shelf life)
We learn from this how important it is to store your long-term food supplies in the coolest place possible; as in a basement, etc..
For long term storage, drier is better. The drier the food and the drier the environment, the longer the shelf life – to a point…
For example, grains should maintain a moisture content of 10% or less. Commercially dried foods easily achieve these levels.
Be aware of the likelihood that typical home dehydrated foods might not result in the same moisture levels as from commercially dried foods, and therefore may not last as long. As a rule of thumb, dried foods with 10% or less moisture will snap easily and are very brittle.
Unless the food is packaged in air-tight containment, then the moisture from the environment will work it’s way in over time and reduce it’s shelf life.