Food contains water. Water is a polar molecule. There are forces in water preventing its molecule from moving freely. Water can be heated with microwaves. Water is said to absorb microwaves.

        Teflon on the hand has no polar molecules, it does not absorb microwaves. It is transparent to microwaves. That is microwaves can pass through a piece of teflon without any loss even though teflon is opaque to our eyes or light waves

        Microwave absorption is characterised by the material microwave properties. They consist of dielectric constant and loss factor

                     loss factor = 0.01 low absorption

                     loss factor = 0.1   medium absorption

                     loss factor = 1.0   high absorption

Processing with high power microwaves, microwave UHT of goat milk, high power dielectric properties measurement, hot complex permittivity measurement

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Microwave Technology

  What are microwaves?

  EM Energy

  Non-ionising Radiation

  Microwave Absorption

  Microwave Quantum

Microwave Simulation

  Maxwell's Equations

  Dielectric Measurement

  Properties of Water

  Properties of Ethanol

  Standing Waves

  Travelling Waves

  Field Patterns


Microwave Machines


  Timber Drying

  Timber Moulding

  Oil Extraction

  Liquid Steriliser

  Wheat Disinfection

  Bean Sterilising

  Fish Thawing

  Bread Thawing

  Rice Treatment


  Floorboard Drying

  Chemical Processing

  Ceramic Kiln

  V.F.M Kiln

  Tyre Recycling

Microwave Research

  Metal Extraction

  Sapstain Treatment

  Growth Stress

  Microwave Ignition