Assessment of heating profiles in model food systems heated by different microwave generators: Solid-state (semiconductor) versus traditional magnetron technology

Effect of Vertical and Horizontal Sample Orientations on Uniformity of Microwave Heating Produced by Magnetron and Solid-State Generators

“…Since the primary goal was to compare the effect of different sample orientations on the heat uniformity of the model food systems, it was important to expose them to a similar level of absorbed power in similar orientations in both solid-state and magnetron microwave systems. In other words, for an impartial comparison of each orientation in both microwave systems, the equivalent output power levels for both microwave systems in each orientation should be adjusted to lead to similar levels of absorbed power in the samples [ 11 ]. In this study, the output power level of 300 W was picked for all samples processed in different orientations in the magnetron microwave system.…”

“…One promising technology is the application of solid-state microwave generators instead of magnetrons [ 1 , 8 , 9 , 10 , 11 ]. In solid-state microwave technology, the initial phase of the varying field can be controlled at any electromagnetic inlet port and, thus, the position of the nodes and antinodes can be changed in a targeted manner.…”

“…Moreover, shape [ 15 ], position, and orientation of the samples are factors to improve microwave heating uniformity [ 11 ]. In the paper by Taghian Dinani, Hasić, Auer, and Kulozik (2020) [ 16 ], we compared three different shapes of samples including spherical, cylindrical, and cuboid shapes.…”

“…In this paper, the cuboid shape was suggested as the best, perfectly showing the changes of microwave field distribution. Taghian Dinani, Kubbutat, and Kulozik (2020) [ 11 ] compared two positions of cuboid samples in both magnetron and solid-state systems: at the center and near the edge of the turntable. However, the orientation of cuboid samples in the center of the turntable has not been investigated until now.…”

“…In other words, the application of the time-temperature mapping technique of the Maillard chemical marker method is an appropriate tool to monitor microwave heat uniformity inside the microwave heated samples for the optimization and controlling of microwave processes [ 20 , 21 , 22 , 23 ]. Moreover, this method offers a reliable and fast visual and optical procedure to detect the position of cold and hot spots in the heated sample [ 11 , 24 ]. To analyze the heating patterns of samples, Maillard reaction-related color changes and temperature distribution measured by an infrared camera were used.…”