Pulse Duration and Efficiency of Soft Cellular Tissue Disintegration by Pulsed Electric Fields Francesca De Vito & Giovanna Ferrari & Nikolai I. Lebovka & Nikolai V. Shynkaryk & Eugéne Vorobiev Received: 30 May 2007 / Accepted: 9 August 2007 / Published online: 15 September 2007 # Springer Science + Business Media, LLC 2007 Abstract The effect of pulse duration on efficiency of disintegration of apple tissue by pulsed electric fields (PEF) was studied. The samples (26-mm diameter, 10-mm height) were treated by PEF at electric field strength E between 100 and 400 V/cm, pulse duration t i of 10, 100, 1,000 μs, inter- pulse duration Δt of 100 μs and different number of pulses n. Both the degree and the time evolution of tissue damage were quantified by electrical conductivity disintegration index Z and characteristic damage time τ, respectively. The samples exposed to the same PEF treatment time nt i showed noticeably higher disintegration efficiency for larger pulse duration. The synergism of PEF and thermal treatment with temperature T (20–50 °C) was demonstrated. The Arrhenius dependence of τ(T) for PEF treatment at E =100 V/cm gave the decreasing activation energy W as a function of t i ,(Q ≈ 164 kJ/mol at t i =10 μs, Q ≈ 109 kJ/mol at t i =100 μs and Q ≈ 66 kJ/mol at t i =1,000 μs). Textural relaxation data supported the higher damage efficiency for longer pulse duration. Keywords Electroporation . Pulsed electric fields . Pulse duration . Soft cellular tissue . Apple . Texture Abbreviations PEF pulsed electric fields Nomenclature C specific capacitance of cell membrane (F/m 2 ) D sample diameter (mm) E electric field strength (V/cm) F force (N) h sample height (mm) h m membrane thickness (nm) n number of pulses N number of trains r 2 coefficient of determination R radius of a spherical cell (m) R g =8.314 J K -1 mol -1 , the universal gas constant t c membrane charging time (s) t I pulse duration (s) t PEF total time of electrical treatment (s) Δt inter-pulse duration (s) Δt t inter-train pause (s) T temperature (°C) Q activation energy (kJ/mol) u m transmembrane potential (V) Food Bioprocess Technol (2008) 1:307–313 DOI 10.1007/s11947-007-0017-y F. De Vito : G. Ferrari Centro Regionale di Competenza Produzioni Agroalimentari, University of Salerno, Via Ponte don Melillo, 84084 Fisciano (Salerno), Italy G. Ferrari Department of Chemical and Food Engineering, University of Salerno, Via Ponte don Melillo, 84084 Fisciano (Salerno), Italy N. I. Lebovka : N. V. Shynkaryk : E. Vorobiev Departement de Génie des Procédés Industriels, Université de Technologie de Compiègne, Centre de Recherche de Royallieu, B.P. 20529-60205, Compiègne Cedex, France N. I. Lebovka : N. V. Shynkaryk Institute of Biocolloidal Chemistry, 42, blvr. Vernadskogo, Kiev 03142, Ukraine E. Vorobiev (*) Département Génie Chimique Laboratoire de Génie des Procédés Industriels, Université de Technologie de Compiègne, UMR CNRS 6067, BP 20529 60205, Compiègne, France e-mail: eugene.vorobiev@utc.fr