Continuous tubular microwave heating of homogeneous foods: evaluation of heating uniformity
Journal article, 2016

A pilot-scale process for continuous in-flow microwave processing of foods, designed and implemented at SP Food and Bioscience, was evaluated for heat treatment of a homogeneous model food for high-temperature short-time (HTST) conditions, at constant total input microwave power, at 2450 MHz. The microwave system has three consecutive cavities, one excited by the TM020 microwave mode that heats primarily in the tube centre, and two TM120 mode cavities that heat primarily in the tube periphery. The temperature uniformity of the homogeneous model food after microwave heating is here evaluated in terms of spatial distribution, for different set-ups of input microwave power in each cavity and for different order of the placement of the cavities, while maintaining the total input microwave power. The microwave heating uniformity is evaluated, based on measured and calculated radial temperature profiles. Combined TM020 and TM120 heating was found to result in more uniform heating by means of spatial temperature uniformity over the tube cross section. Furthermore, appropriately selected microwave power distribution between the centre and periphery heating cavities results in a stable heating profile in the studied food, that differs only about 10 °C or less between highest and lowest average values directly after microwave heating.

microwave pasteurization

microwave-assisted HTST system

continuous process

microwave tubular heating

homogeneous foods

Microwave in-flow heating

pumpable food

Author

Birgitta Wäppling Raaholt

SIK – the Swedish Institute for Food and Biotechnology

Sven Isaksson

SIK – the Swedish Institute for Food and Biotechnology

Lars Hamberg

SIK – the Swedish Institute for Food and Biotechnology

Andreas Fhager

Chalmers, Signals and Systems, Signal Processing and Biomedical Engineering

Yngve Hamnerius

Chalmers, Signals and Systems, Signal Processing and Biomedical Engineering

Journal of Microwave Power and Electromagnetic Energy

0832-7823 (ISSN)

Vol. 50 1 43-65

Subject Categories

Electrical Engineering, Electronic Engineering, Information Engineering

DOI

10.1080/08327823.2016.1157318

More information

Latest update

8/24/2018