A process for sealing a thermoplastic based food container characterized in that after filling, the container is sealed by an intermediate membrane made of a microporous plastic gas-breathable material, gas is extracted from the headspace through the membrane and afterwards the container is sealed by...http://www.google.co.uk/patents/US4513015?utm_source=gb-gplus-sharePatent US4513015 - Method of sealing a container and removing air headspace
