Microwave unit for continuous heat treatment of poultry muscle stomachs

BACKGROUND: The volume of processed chicken muscle stomachs as meat raw materials in Russia is 0.1-0.15 million tons per year. Therefore, the implementation of microwave technology for heat treatment of such raw materials is relevant. OBJECTIVE: Development of a radio-proof unit with a conical resonator for heat treatment of poultry muscle stomachs in continuous operation at high electric field strength in farm conditions. METHODS: The raw material is chicken muscle stomachs. The innovative idea is that the muscular stomach as a multicomponent raw material, pre-crushed with an electrically driven grating disc, is grinded with the abrasive coils of an electrically driven auger during dielectric heating in continuous mode in a conical resonator, ensuring high electric field strength and electromagnetic safety by truncating the cone at the critical surface level. The study of the raw materials heating temperature was carried out using the Testo 845 infrared thermometer, and the distribution of the electric field in the resonator was carried out in the CST Microwave Studio 2018 software. RESULTS: In a conical resonator, where a grating disk is installed under the base with a gap of no more than a quarter of the wavelength, a fluoroplastic electrically driven auger with screws coated with an abrasive material is installed coaxially. The diameters of the screws change with the change in the diameter of the resonator. The resonator is truncated at the critical section level. The results of a study of the dynamics of dielectric heating of a chicken muscular stomach at specific capacities of 3.3–7 W/g show that they will be cooked in 3–4 minutes. The specific energy costs for heat treatment of raw materials in the unit with a power consumption of 4.15 kW and a capacity of 30 kg/h are 0.14 kWh/kg. The intrinsic Q−factor of the resonator is 77200, the electric field strength is 4–5 kV/cm. CONCLUSIONS: A new design solution for a radio-tight installation containing a truncated conical resonator, a grinding disk made of non-ferromagnetic material, a fluoroplastic screw with an electric drive, the screw pitch of which is no more than two depths of wave penetration into the raw material, made it possible to create a design of a working chamber for the heat treatment of avian muscles stomachs in a continuous mode at high electric field strength in farm conditions.