Microwave sterilization and vacuumizing of products in flexible packages and apparatus therefor

• US 3,261,140 A
• Filed: 08/30/1963
• Issued: 07/19/1966
• Est. Priority Date: 08/30/1963
• Status: Expired due to Term

• Current Assignee: Florren E. Long, Fred B. Shaw, Harvey C. Lisle
• Original Assignee: Florren E. Long, Fred B. Shaw, Harvey C. Lisle
• Inventors: Long, Florren E., Shaw, Fred B., Lisle, Harvey C.
• Application Number:
  US04/305,750
• Time in Patent Office: 1,054 Days
• US Class Current: 53/428
• CPC Class Codes: A23L 3/01 using microwaves or dielectric heating
• CPC Class Codes: A23L 3/04 with packages on endless chain or band conveyors A23L3/022 takes precedence
• CPC Class Codes: B65B 55/06 by heat
• CPC Class Codes: B65B 55/16 by irradiation

Claims

1. AN IMPROVED METHOD OF SIMULTANEOUSLY STERILIZING AND VACUUMIZING A PRODUCT COMPRISING, PARTIALLY FILLING AN OPEN TOPPED POUCH OF LOW DIELECTRIC CONSTANT POLYMERIC MATERIAL WITH A MOISTURE CONTAINING PRODUCT HAVING A RELAVIDE A HEAD SPACE THEREOVER, SAID PRODUCT HAVING A RELATIVELY HIGH DIELECTRIC CONSTANT, SEALING PORTIONS OF THE TOP OF SAID POUCH ABOVE SAID HEAD SPACE SO AS TO PROVIDE A VENT FOR VOLATILES THERETHROUGH, PASSING THE THUS PARTIALLY PACKAGED PRODUCT THROUGH A ZONE OF ELECTROMAGNETIC ENERGY WITHIN THE MICROWAVE RANGE TO THEREBY QUICKLY HEAT SAID PRODUCT TO A TEMPERATURE OF ABOUT 100 DEGREES C. AND TO QUICKLY PRODUCT LARGE AMOUNTS OF STEAM BY VAPORIZATION OF THE MOISTURE PRESENT IN SAID PRODUCT, MAINTAINING THE WALLS OF SAID POUCH AGAINST EXPANSION SO AS TO PREVENT EXCESSIVE BALLOONING OF THE POUCH WALLS DEFINING SAID HEAD SPACE, RAPIDLY VENTING THE POUCH OF AIR AND STEAM PRODUCED BY SAID RISE IN TEMPERATURE, AND IMMEDIATELY THEREAFTER ENTIRELY SEALING THE TOP OF SAID POUCH SO AS TO PROVIDE A VACUUM PACKAGE OF A STERILE PRODUCT.