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Effect of Microwave Power Cycle on Temperature Uniformity, Microbial Inactivation, and Quality: Computational
Ozan Karataş1, Elif Nida Çakır1, Ferruh Erdoğdu2
1Department of Food Engineering. Graduate School of Natural and Applied Sciences, Ankara University, Ankara, Turkey.
Journal of Food Science
|July 20, 2026
Summary
Microwave processing power cycling significantly impacts microbial safety and food quality. Different on-off settings create unique temperature histories, affecting inactivation and enzyme degradation, not just average power.
Area of Science:
- Food Science and Technology
- Microwave Processing Engineering
- Food Safety and Quality Assurance
Background:
- Microwave power control uses on-off cycling or continuous methods.
- Previous research focused on temperature uniformity, neglecting microbial safety and quality impacts of power cycling.
Purpose of the Study:
- Investigate the effect of different on-off power cycle configurations on temperature, microbial, and enzymatic inactivation kinetics.
- Determine implications for food safety and quality in microwave processing.
Main Methods:
- Utilized a finite element-based multiphysics model.
- Simulated microwave processing of milk with varying power cycle settings at a fixed duty cycle (0.5).
- Analyzed temperature evolution, microbial inactivation, and enzymatic (GGT) inactivation.
Main Results:
- Different power cycles yielded distinct temperature increase rates, despite identical final temperatures and absorbed power.
- Microbial inactivation kinetics varied substantially with power cycle settings.
- Enzymatic quality degradation (GGT inactivation) was significantly influenced by power cycles, necessitating a balance between safety and quality.
Conclusions:
- Power cycle-induced temperature profiles are critical for microwave processing safety and quality outcomes.
- Reporting explicit power cycle settings is essential for ensuring repeatability and comparability in microwave processing.
- Industrial microwave processes require careful selection and monitoring of power cycle configurations beyond average power inputs to control safety and quality effectively.
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