Microwave Heating of Liquid Foods

Vittorio Romano, Rino Apicella

Dipartimento di Ingegneria Industriale, Università degli Studi di Salerno, Fisciano, Italy.

DOI: 10.4236/eng.2015.76026                

Abstract

A mathematical model has been formulated to describe the heat transfer in liquid foods flowing in circular ducts, subjected to microwave irradiations. Three types of liquids with different rheological behavior are considered: skim milk (Newtonian), apple sauce and tomato sauce as non-New-tonian fluids. Each one can flow with different velocities but always in laminar way. The temperature profiles have been obtained solving the transient momentum and heat equations by numerical resolution using the Finite Element Method. The generation term due to the microwave heating has been evaluated according to Lambert’s law. Dielectric properties are considered to be temperature dependent.

Keywords

Continuous Microwave Heating, Lambert’s Law, Non-Newtonian Fluids, FEM

Conflicts of Interest

The authors declare no conflicts of interest.

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