How to extend the shelf life of dried food
In order to maximise the storage life of certain types of food, it is possible to employ a variety of different methods, including the obvious (such as freezing), or traditional methods such as pickling or smoking. However, for many types of dry ambient foods such as rice, cereals, dehydrated fruit and vegetables, dried beans and pasta, repacking them in airtight packs with the inclusion of oxygen absorbers can significantly extend their shelf life, resulting in super long life foods.
What form of airtight packaging can be used?
Common solutions are sealed glass jars, cans and heat-sealed multi-laminate bags.
What are oxygen absorbers?
Oxygen absorbers are small packets of activated carbon or non-toxic iron powder.
They are designed to remove oxygen from air, specifically when packaging dry foods. When you place an oxygen absorber into an airtight container or package, the oxygen inside is attracted to the iron in the oxygen absorber. As a consequence, the oxygen is removed from the air in the pack, leaving only nitrogen. As long as the pack is completely sealed, without oxygen the shelf life of the food increases substantially - up to 30 years in some cases.
How do oxygen absorbers increase shelf life?
- They prevent bacterial growth in the food.
- They preserve vitamins such as A, C, and E that are otherwise depleted when exposed to oxygen
- They prevent organoleptic changes to the food. I.e. changes to the flavour, aroma, texture, feel or visual appearance.
How can I do this myself?
To establish super long life foods by extending the shelf life of your standard food using this method, you will need to obtain:
- Oxygen absorbers (200cc packets are usually around £0.25 each)
- Multi-laminate bags (vary depending on size)
- A heat-sealing machine (available on Amazon for under £20)
Simply empty the food from the original packaging, then place an oxygen absorber with the food into a food-grade multi-laminate pouch, constructed from material that includes an aluminium layer of at least 14 microns. Once the pouch has been fully sealed across the open end (ensuring that there is good seal integrity) then the shelf-life of the food will be far greater than its original packaging.
Good seal integrity requires the following:
- The temperature needs to be high enough to adequately melt the internal plastic layer
- The pressure applied by the heat sealer needs to ensure that it facilitates the creation of a strong bond
- The pressure needs to be applied long enough for the plastic layers to melt
- The seal needs to be free of contamination, such as food particles or crumbs
We encourage you to locate these items at the best possible price from a reputable source, however we are also happy to say that you can buy competitively priced oxygen absorbers and food-grade multi-laminate bags directly from us if you desire.
If you require a bulk quantity, please contact us for the best possible pricing.