VALIDATION OF A SIMPLIFIED NUMERICAL MODEL FOR HOT‐AIR TREATMENT OF EGG SHELL SURFACE

The aim of the study was to simulate a hot-air-based treatment of the egg shell by a simplified finite element model. The calculated temperatures were compared with experimental data observed on an egg shell instrumented with thermocouples. A simple plant was used to make eggs roll while hot and cold air jets impinged the shell on opposite sides. The results have shown good agreement between calculated and observed temperatures on the inner part of the shell, despite the simplicity of the 2D numerical model. The observed temperature profiles, compatible both with albumen coagulation condition and shell pasteurization, support the hot air treatment as a possible and innovative surface decontamination technique for table eggs. PRACTICAL APPLICATIONS As hot-air decontamination is an innovative one, several tests will be necessary to assess the technique and to engineer the process. Unfortunately, each trial needs a number of microbial and quality tests requiring a remarkable amount of time and money. The numerical model made possible the testing of several thermal cycles, optimizing the value of the process parameters involved, reducing experimental effort. Moreover, the 2D model enhanced the advantages, with respect to the full 3D model, balancing an acceptable feasibility loss with much shorter calculus time.

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