Cellulose food casing manufacturing method

摘要

In a method for forming a cellulose tube T suitable for use as a food casing, in which a solution of nonderivatized cellulose, tertiary amine N-oxide and water is extruded through a die gap 18 and the extruded tube is downwardly drawn through an air gap while being internally cooled and then is passed into a water bath 21, the tube transverse direction tensile strength being increased by drawing the extruded tube through an air length of at least about five inches (127 mm) and exposing the exterior surface of the extruded tube to cooling air in the air gap. The cooling air flow is formed by a downwardly flowing air curtain formed by apertures 62 in an air ring 61 connected to a vortex tube 64 itself connected to a source of pressurised air P. <IMAGE>