Effect of apparent density of sliced food particles on the efficiency of pulsed electric field treatment

This work discusses the effects of pulsed electric field (PEF) (electric field strength, E, 100–1000 V; pulse duration, tp, 100 μs) on disintegration of potato slices treated between parallel plate electrodes by using a laboratory compression chamber equipped with a PEF-treatment system. The apparent density of slices (bed of particles), ρ, was varied within 0.313 g/cm3 and 1 g/cm3. The electrical conductivity σ(ρ) of the packing of slices versus volume fraction of particles ϕ was approximated by the percolation law σ ∝ (φ − φc)t, where ϕc ≈ 0.290, t = ti ≈ 0.46 and t = td ≈ 1.39 for the intact and completely damaged tissues, respectively. The impact of electric field strength and apparent density of slices on PEF-induced damage kinetics was studied. The more accelerated kinetics of damage was observed for more dense packing of slices. The approximated relation between the applied, E, and effective, Ee, electric field strengths accounting for the σ(ρ) dependence was derived.Industrial relevanceThe practical applications of PEF treatment (e.g., pressing, drying, extraction, etc.) demand operations with slices of food particles. In this study, research towards the electroporation efficiency of PEF applied to the porous packing of sliced food particles is provided.

► Effects of pulsed electric field (PEF) on disintegration of potato slices were studied.
► Effective electrical conductivity of packed slices followed the percolation law.
► Efficiency of PEF treatment was determined by apparent density.
► Kinetics of PEF-induced damage was faster for more dense packing.