Development of a Continuous Pulsed Electric Field (PEF) Vortex-Flow Chamber for Improved Treatment Homogeneity Based on Hydrodynamic Optimization
| Autor: | Pauline Eppmann, Justus Knappert, Anna Krottenthaler, Tobias Horneber, Christopher McHardy, Henry Jaeger, Felix Schottroff, Cornelia Rauh |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
0301 basic medicine
Histology Materials science lcsh:Biotechnology Biomedical Engineering Bioengineering 02 engineering and technology Computational fluid dynamics 600 Technik Technologie pulsed electric fields (PEF) treatment chamber design differentiation of thermal and electric field effects 03 medical and health sciences non-thermal inactivation of microorganisms process optimization lcsh:TP248.13-248.65 Electric field ddc:570 Thermal Homogeneity (physics) Process optimization effects of PEF on alkaline phosphatase Original Research proof of concept business.industry Bioengineering and Biotechnology Mechanics Vorticity PEF 021001 nanoscience & nanotechnology Vortex 030104 developmental biology pulsed electric fields Flow velocity numerical simulation 0210 nano-technology business ddc:600 570 Biowissenschaften Biologie Biotechnology |
| Zdroj: | Frontiers in Bioengineering and Biotechnology Frontiers in Bioengineering and Biotechnology, Vol 8 (2020) |
| Popis: | Pulsed electric fields (PEF) treatment is an effective process for preservation of liquid products in food and biotechnology at reduced temperatures, by causing electroporation. It may contribute to increase retention of heat-labile constituents with similar or enhanced levels of microbial inactivation, compared to thermal processes. However, especially continuous PEF treatments suffer from inhomogeneous treatment conditions. Typically, electric field intensities are highest at the inner wall of the chamber, where the flow velocity of the treated product is lowest. Therefore, inhomogeneities of the electric field within the treatment chamber and associated inhomogeneous temperature fields emerge. For this reason, a specific treatment chamber was designed to obtain more homogeneous flow properties inside the treatment chamber and to reduce local temperature peaks, therefore increasing treatment homogeneity. This was accomplished by a divided inlet into the chamber, consequently generating a swirling flow (vortex). The influence of inlet angles on treatment homogeneity was studied (final values: radial angle α = 61°; axial angle β = 98°), using computational fluid dynamics (CFD). For the final design, the vorticity, i.e., the intensity of the fluid rotation, was the lowest of the investigated values in the first treatment zone (1002.55 1/s), but could be maintained for the longest distance, therefore providing an increased mixing and most homogeneous treatment conditions. The new design was experimentally compared to a conventional co-linear setup, taking into account inactivation efficacy of Microbacterium lacticum as well as retention of heat-sensitive alkaline phosphatase (ALP). Results showed an increase in M. lacticum inactivation (maximum Δlog of 1.8 at pH 7 and 1.1 at pH 4) by the vortex configuration and more homogeneous treatment conditions, as visible by the simulated temperature fields. Therefore, the new setup can contribute to optimize PEF treatment conditions and to further extend PEF applications to currently challenging products. |
| Databáze: | OpenAIRE |
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