a method of preserving foodstuffs by placing them in a container of given volume in which air at atmospheric pressure is present and selectively removing the oxygen from the air in the container while maintaining substantially atmospheric pressure therein is disclosed . according to the invention , a flow of air is established through the container by means of an external conduit in which the oxygen in the air is catalytically reacted with hydrogen gas concurrently generated and added to the air flow for at least a predetermined length of time after which the generation and addition of hydrogen gas is terminated when the hydrogen / oxygen reaction falls below a given level . various embodiments of the apparatus for practicing the method according to this invention are described .