title: Frequency Distribution in Domestic Microwave Ovens and Its Influence on Heating Pattern.
abstract: In this study, snapshots of operating frequency profiles of domestic microwave ovens were collected to reveal the extent of microwave frequency variations under different operation conditions. A computer simulation model was developed based on the finite difference time domain method to analyze the influence of the shifting frequency on heating patterns of foods in a microwave oven. The results showed that the operating frequencies of empty and loaded domestic microwave ovens varied widely even among ovens of the same model purchased on the same date. Each microwave oven had its unique characteristic operating frequencies, which were also affected by the location and shape of the load. The simulated heating patterns of a gellan gel model food when heated on a rotary plate agreed well with the experimental results, which supported the reliability of the developed simulation model. Simulation indicated that the heating patterns of a stationary model food load changed with the varying operating frequency. However, the heating pattern of a rotary model food load was not sensitive to microwave frequencies due to the severe edge heating overshadowing the effects of the frequency variations.
authors.affiliation: Engineering Research Center of Food Thermal-processing Technology and Dept. of Food Science and Technology, Shanghai Ocean Univ., Shanghai, 201306, China.|Dept. of Biological Systems Engineering, Washington State Univ., Pullman, WA, 99164-6120, U.S.A.
authors.forename: Donglei
authors.initials: D
authors.lastname: Luan
authors.affiliation: Engineering Research Center of Food Thermal-processing Technology and Dept. of Food Science and Technology, Shanghai Ocean Univ., Shanghai, 201306, China.|Dept. of Biosystems Engineering, Auburn Univ., Auburn, AL, 36849, U.S.A.
authors.forename: Yifen
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Dept. of Biological Systems Engineering, Washington State Univ., Pullman, WA, 99164-6120, U.S.A.
authors.forename: Juming
authors.initials: J
authors.lastname: Tang
authors.affiliation: Dept. of Biological Systems Engineering, Washington State Univ., Pullman, WA, 99164-6120, U.S.A.
authors.forename: Deepali
authors.initials: D
authors.lastname: Jain
mesh_terms: D003198:Computer Simulation; D003296:Cooking / Q000295:instrumentation*; D005502:Food; D006358:Hot Temperature; D008872:Microwaves; D008962:Models, Theoretical; D015203:Reproducibility of Results
keywords: computer simulation; frequency distribution; heating pattern; microwave oven; operating frequency