There are six conditions to be aware of when storing food for emergency preparedness food storage, or outdoor recreation. The foods being referred to in this post are shelf-stable freeze-dried, dehydrated, dried commodities. Optimal storage conditions can also be applied to wet pack: retort, MRE’s, canned goods, and other specialty longer term wet pack foods.
- Temperature- This is the primary factor effecting the storage life of foods. The cooler the better. 40 degrees-50 degrees would be great. Room temperature (65 degrees-72 degrees) or below is generally fine. Avoid above 90 degrees for extended periods of time. The longer food is exposed to very high temperatures the shorter the edible life and the faster the degeneration of nutritional value. Note: There are some “foods” available for emergency preparedness that are known as “emergency food or ration bars.” These products are generally referred to as “life raft bars” because they were originally designed for life rafts and can withstand high heat for extended periods of time. They primarily consist of white sugar and white flour, and were not meant to be the sole source of nutrition for a long period of time.
- Moisture- The lower the better. Moisture can deteriorate food value rapidly and create conditions that promote the growth of harmful organisms. The moisture level contained in foods varies depending on the type of product it is. Have foods in moisture barrier containers (metal, glass) in high humidity areas. Note: Mylar bags or plastic buckets are not a long term (over 3 years) moisture or oxygen barrier. The moisture and gas transmission rates through these materials vary depending upon the specifications of the manufacturers. Plastic absorbs gases, moisture, and odors. Note: Be careful where you store dry foods in cans. Very cold flooring or any condition where there is a dramatic temperature differential may cause a build up of condensation inside the container.
- Oxygen – A high oxygen environment causes oxidation, which leads to discoloration, flavor loss, odors, rancidity and the breakdown of nutritional value in foods. It also allows insects to feed on dried food reserves. Without oxygen, insects cannot live, nor can aerobic (oxygen dependent) organisms. Whole grain and beans have natural oxygen barriers and can store for long periods of time in low humidity and if free from infestation. All other processed grains, vegetables, fruits, etc. must be in a very reduced (2% or less) oxygen environment for long term storage. Note: Mylar bags or plastic buckets are not a long term (over 3 years) moisture or oxygen barrier. The moisture and gas transmission rates through these materials vary depending upon the specifications of the manufacturers. Plastic absorbs gases, moisture, and odors. The best long term storage containers are glass and metal.
- Infestation – Examples include rodents, insects in all their stages of growth, mold, microorganisms, and any other creatures who get hungry – large or small. The proper packaging and storage conditions are required to control infestation and not allow critters to both get into the food, or have the necessary environment for them to flourish if they are sealed into a container – such as in the form of eggs or spores.
- Handling – Rough handling can not only damage the food itself, but it can also adversely effect and compromise the integrity of the container in which the food is stored. Glass of course can break, any pouched item can develop pin holes, tears, or cracks. The seams on buckets and cans can be tweaked, twisted, or damaged to allow oxygen to enter the container.
- Light – Food should not be stored in direct sunlight. Both for the potential of high temperature, and its affect on food value. Sunlight directly on stored foods can destroy nutritional value and hasten the degeneration of food quality, taste, and appearance. Foods packed in light barrier containers do not pose a problem with the affects of light.
Please refer to the important article Food Storage Packing Do-it-Yourself Facts and Myths dealing with specific techniques, containers, products, and additives used for packing foods for long term storage.