Microwave freeze drying: An experimental investigation

✍ Scribed by T.K. Ang; D.C.T. Pei; J.D. Ford

• Book ID: 103004195
• Publisher: Elsevier Science
• Year: 1977
• Tongue: English
• Weight: 976 KB
• Volume: 32
• Category: Article
• ISSN: 0009-2509
• DOI: 10.1016/0009-2509(77)80245-5

✦ Synopsis

ticrowave freeze-drymg experiments have been carned out with l/4-3/4 m beef cubes, over a range of pressures and at various field strengths For a 1/2m cube at a field strength of lOOV/cm, the drymg me IS approximately 6 67 hr The maxunum apphcable field strength 1s 130 V/cm, gwmg a drymg Qme of 4 33 hr Beyond tis field strength, meltmg of the Ice-core and/or overheahng of the dried layer wdl occur Expenmental drymg curves and temperature profiles (m dried and frozen regions) are found to be m good agreement with the predictions of the previously presented two dunenslonal freeze-drying model Total pressure 1s found to have a slgmficant effect on sample temperature, but lrttle miluence on the overall drymg tame, due to couplmg It 1s concluded that the lowest possible pressure should be used m mlcrowave freeze-drymg, although pressures below a lumtmg value of 200 pm do not seem necessary ' -