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Mathematical model of solid food pasteurization by ohmic heating: influence of process parameters
1Dipartimento di Ingegneria Industriale, Università degli Studi di Salerno, Via Giovanni Paolo II 132, 84084 Fisciano, Italy.
Thescientificworldjournal
|February 28, 2014
Summary
This study models ohmic heating pasteurization, revealing cold spots on external shells due to heat loss. Optimizing process parameters can lead to more uniform food pasteurization.
Area of Science:
- Food Science and Technology
- Mathematical Modeling
- Heat Transfer
Background:
- Ohmic heating is a food pasteurization method.
- Heat loss to the environment during ohmic heating is a known issue.
- Previous models often focus on internal temperature distribution.
Purpose of the Study:
- To analyze the pasteurization of solid food using ohmic heating with a mathematical model.
- To investigate the impact of temperature gradients and heat loss on pasteurization uniformity.
- To identify critical areas for monitoring during the ohmic heating process.
Main Methods:
- Developed a mathematical model solving Laplace's equation for electrical potential and the heat transfer equation.
- Incorporated temperature-dependent thermophysical and electrical properties.
- Simulated microbial inactivation kinetics alongside heat transfer.
Main Results:
- The model predicts colder external shells at electrode-sample junctions due to heat loss.
- Temperature gradients near the outer surface are critical, not just internal points.
- Analysis shows process parameters influence temperature distribution.
Conclusions:
- External shells are critical monitoring areas for ohmic heating pasteurization.
- Understanding temperature distribution is key to reducing temperature differentials.
- This model aids in achieving more uniformly pasteurized food products.
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