Keep Your Food Safe from Rot and Pests
You must remove all the oxygen from your long-term mylar food storage bags because it will spoil or otherwise harm your food if you don't. Oxygen can react directly with elements in the food, making fats and oils go rancid or changing protein structures. Furthermore, oxygen can cause discoloration and loss of flavor, vitamins, and other nutrients. Using an oxygen absorber that contains iron will use all the oxygen before it can alter the composition of your food.
Oxygen also supports the growth of contaminants within your food. For example, if fungi are present, such as yeast, mold, or mildew, oxygen will allow them to grow. In addition, any worms, eggs, larvae, or insects will survive and thrive with oxygen. Finally, many smaller microorganisms also require oxygen, and they can spoil or devour your stored provisions. Oxygen absorbers will quickly deprive the dangerous contaminants of the oxygen they need to live in your food stores.