Transactions of the ASAE · 1995 · 127 citations · 0 references
AgricultureFood ScienceMicrobiologyFood EngineeringFood PreservationFood ProcessingFood Bioprocess EngineeringNonthermal ProcessingElectric Field OptimizationElectrode GeometryElectrode Geometry OptimizationEscherichia ColiMicrobial InactivationPasteurizationPulsed Electric Field InactivationPulsed Electric Field Treatment
High‑voltage pulsed electric field (PEF) treatment is a promising nonthermal method that could transform liquid food preservation, with the treatment chamber being a key component. The study aimed to design a PEF treatment chamber using an electric‑field optimization technique. The authors used finite‑element analysis to optimize electrode geometry, built parallel‑plate and coaxial chambers, and tested them with exponential and square waveforms at 20–50 kV cm⁻¹ and 2–20 ms pulses. The optimized coaxial chamber delivered a uniform field without hotspots and achieved over seven log reductions of *E.
High voltage pulsed electric field (PEF) treatment is a promising nonthermal processing method that may radically change liquid food preservation technology. One of the key components in the PEF pasteurization process is a treatment chamber. In this work, the chamber was designed with the aid of an electric field optimization technique. The finite element method was used in the numerical analysis of electric fields and for optimization of the electrode geometry. Using the optimized electrodes in the coaxial treatment chamber, a prescribed field distribution in foods was achieved without points of electric field enhancement. Two types of treatment chambers, parallel plate and coaxial electrode, were constructed and tested. Microbial inactivation tests were conducted using exponential decaying and square waveforms. Electric field intensity ranged from 20 to 50 kV/cm, while pulse length ranged from 2 to 20 ms. More than seven log cycles of microbial inactivation of Escherichia coli and Saccharomyces cerevisiae were achieved when the food temperature was maintained below 30 C.