Fuente: WIPO "tomato" A method of forming a rigid plastic tray suitable for oxygen-sensitive products, the method comprising the steps of mixing PET with an oxygen scavenging polymeric composition in an extruder device comprising at least one extruder screw and a melt-processing zone, wherein the PET has an antimony content of less than 46 ppm; commuting the PET and the oxygen scavenging composition through the melt-processing zone of the extruder at a temperature of from about 250 to 300° C., at a total cycle time of less than about 6 minutes and a pressure of from 0 to 900 psig, to form a melted plastic mixture; extruding the melted plastic mixture into a sheet material; thermoforming the sheet material into a rigid plastic tray.