Methods of absorbing oxygen are disclosed with the use of compositions useful as oxygen absorbers. The compositions are generally salts of unsaturated fatty acids that have one or more carbon to carbon double and or triple bonds. The compositions may be prepared by reacting an unsaturated fatty acid with a hydroxide resulting in a salt of the unsaturated fatty acid. Water soluble compositions are dissolved in aqueous solutions for the purpose of absorbing oxygen from the aqueous solutions and or their containers. Water insoluble compositions are protected from moisture due to their water repellent character and this characteristic is used advantageously in order to absorb oxygen from containers that may contain moisture where it is desired that the compositions remain relatively unaffected by moisture, intact and remain where they are placed.