A microwave heater comprises a cylindrical housing having an inner surface defining an internal cavity. A microwave generator is secured adjacent a first end of the housing and received inside the internal cavity is a sample holder that comprises an annular base member positioned adjacent the first end has a central axis coinciding with a longitudinal axis of the housing. A first opening is formed along the central axis, an outlet of the microwave generator extending through the first opening along the central axis for emitting into the internal cavity electromagnetic waves centered at a given microwave wavelength. A circular support plate substantially parallel to the base member and concentric therewith, a cavity portion defined therebetween, is separated from the base member by a distance less than the given microwave wavelength for establishing a Transverse Magnetic (TM) 01 mode as a predominant resonance mode inside the cavity portion.

Method and apparatus for industrial microwave (MW)-assisted thermal sterilization and pasteurization using solid-state MW generators. One or more phased array generators heat packaged foods or liquids conveyed in transport carriers through a processing liquid providing supplemental temperature control and hydrostatic pressure. Generator output signals are computer controlled, allowing phase and power-ratio modulation to both adjust interference patterns within heating cavities and shift focus of heating energy.

The invention relates to a method and apparatus for determining a size information of food ingredients. The method comprises a step of applying (110) to the food ingredients an electrical field having a given radio frequency, the electrical field being generated by a source positioned in close proximity to the food ingredients, a first step of measuring (120) a ratio between the energy of the electrical field reflected from the food ingredients, and the energy of the electrical field generated by said source and applied to the food ingredients. The method also comprises a first step of determining (130), based on said ratio, an average thickness of the food ingredients along the direction of the electrical field applied to the food ingredients. The method also comprises a second step of measuring (140), for a plurality of distances between the source of the electrical field and the food ingredients, the ratio (R2) between the energy of the electrical field reflected from the food ingredients, and the energy of the electrical field applied to the food ingredients. The method further comprises a step of identifying (150) a relatively sudden change in the amplitude of the ratios measured by said second step of measuring (140) and a step of deriving (160) the corresponding distance between the source of the electrical field and the food ingredients for which said relatively sudden change occurred. The method also comprises a second step of determining (170), based on said corresponding distance and the divergent angle of the electrical field irradiating at said corresponding distance, an average diameter of the food ingredients in a plane perpendicular to the direction of the electrical field applied to the food ingredients. This invention results in a more convenient, robust and accurate way to determine the average thickness of the food ingredients.

Systems and methods include a cooking appliance comprising a heating element disposed within a cooking chamber and operable to selectively emit waves at any of a plurality of powers and/or peak wavelengths, a camera operable to capture an image of the cooking chamber, and a computing device operable to supply power to the heating element to vary the power and/or peak wavelength of the emitted waves and generate heat within the cooking chamber, and instruct the camera to capture the image when the heating element is emitting at a stabilized power and/or peak wavelength. The computing device is operable to generate an adjusted captured image by adjusting the captured image with respect to the stabilized power and/or peak wavelength. The computing device comprises feedback components operable to receive the adjusted captured image, extract features, and analyze the one or more features to determine an event, property, measurement and/or status.

An apparatus for applying RF energy to process an object may include at least one controller configured to receive EM feedback-related values from an energy application zone, each of the values being associated with a respective MSE. The controller may also be configured to identify a change in one or more of the EM feedback-related values within a period of time; adjust the RF energy application based on the change in the EM feedback-related values identified, and cause application of RF energy to the energy application zone.

A disclosed microwave heating apparatus includes a casing part configured to accommodate an object to be heated; a microwave generator configured to generate a microwave; an electromagnetic wave generator configured to generate an electromagnetic wave whose frequency is different from that of the microwave; an electromagnetic wave sensor configured to measure power of the electromagnetic wave, the power of the electromagnetic wave being measured after the electromagnetic wave incident on the casing part from the electromagnetic wave generator has passed through the object to be heated; and a controller configured to control, based on the power measured in the electromagnetic wave sensor, the microwave generator to generate the microwave.

This disclosure relates to a microwave heating device and a method for operating a microwave heating device, in particular to heat at least one product inside a heating chamber of the device. The microwave heating device comprises at least two radiating portions that are adapted to radiate microwaves to the heating chamber and can be operated according to a plurality of operational configurations that differ in frequency and/or in phase shift(s) between the radiated microwaves. A learning procedure can be executed by sequentially operating the at least two radiating portions in several operational configurations. Energy efficiency data are calculated for those operational configurations. An operating frequency can be selected, the selection being based on energy efficiency data. An operational configuration with a maximum energy efficiency at the selected operating frequency may be taken as a reference. A heating procedure can be executed by sequentially operating the at least two radiating portions in operational configurations having the selected operating frequency and respective phase shift(s) that are chosen around the respective phase shift(s) of the reference operational configuration. The phase shift(s) of each chosen operational configuration may have a phase shift distance from the respective phase shift(s) of the reference operational configuration, such that, in the space of the phase shifts, the reference operational configuration is surrounded by the chosen operational configurations.

This disclosure relates to a microwave heating device and a method for operating a microwave heating device, in particular to heat at least one product inside a heating chamber of the device. The microwave heating device comprises at least two radiating portions that are adapted to radiate microwaves to the heating chamber and can be operated according to a plurality of operational configurations that differ in frequency and/or in phase shift(s) between the radiated microwaves. A learning procedure can be executed by sequentially operating the at least two radiating portions in several operational configurations. Energy efficiency data are calculated for those operational configurations. An operating frequency can be selected via an algorithm that optimizes a mathematical function based on energy efficiency data. An operational configuration with a maximum energy efficiency at the selected operating frequency may be taken as a reference. A heating procedure can be executed by sequentially operating the at least two radiating portions in operational configurations having the selected operating frequency and respective phase shift(s) that are chosen around the respective phase shift(s) of the reference operational configuration.

The invention relates to a method (100) and apparatus for controlling the heating of food ingredients. The method comprises the step of measuring (110) the spectrum of energy absorption of the food ingredients in a given range of radio frequencies. The method also comprises the step of identifying (120), in said given range of radio frequencies, the radio frequency for which the food ingredients have the maximum energy absorption. The method also comprises the step of applying (130) an electrical field to the food ingredients, said electrical field having a radio frequency corresponding to said radio frequency for which the food ingredients have the maximum energy absorption. The step of measuring (110) comprises, for a plurality of selected radio frequencies in said given range of radio frequencies, the steps of: applying an electrical field on the food ingredients having a radio frequency corresponding to a given selected radio frequency in said plurality of selected radio frequencies; and, measuring the ratio between the energy of the radio frequency electrical field reflected or absorbed from the food ingredients, and the energy of the radio frequency electrical field applied to the food ingredients. The plurality of selected radio frequencies are selected from said given range of radio frequencies by the steps of: for each of said given range of radio frequencies, obtaining a penetration depth of an electrical field having a radio frequency corresponding to the given radio frequency into the food ingredients, and including the given radio frequency into the plurality of selected radio frequencies if the penetration depth of the electrical field having radio frequency corresponding to the given radio frequency is equal to or larger than the thickness of the food ingredients in the direction of the electrical field applied to the food ingredients. This invention allows reducing the heating time of food ingredients.

The microwave heating apparatus (100) comprises a cavity (101) arranged to receive a load (102A, 102B), at least two patch antennas (103A, 103B) coupled to the at least one microwave generator (104), and a control unit (105). Each of the at least two patch antennas (103A, 103B) is configured to radiate microwaves into a predefined direct heating zone (108A, 108B) within the cavity proximate the respective patch antenna (103A, 103B). The control unit (105) is configured to select energy levels for each of the at least two patch antennas (103A, 103B) as if the load (102A, 102B) were static and as if there not interference between the at least two patch antennas (103A, 103B).