title: The early stages of Saccharomyces cerevisiae yeast suspensions damage in moderate pulsed electric fields.
abstract: The objectives of this study were to investigate the effects of pulsed electric fields (PEF) application to colloidal suspension of Saccharomyces cerevisiae. The electrical conductivity measurements during the PEF-treatment of S. cerevisiae suspensions were used to monitor the extent of cell damages in the intervals of electric field strength E = 3-15 kV/cm and time of PEF treatment t(PEF) = 10(-4) to 1s. At relatively small fields (E < 7.5 kV/cm) the early stages of yeast cells damages were observed. At such treatment conditions, the damage was incomplete and developed at long time of PEF treatment, below the value of E = 7.5 kV/cm which is commonly referred in literature as a threshold for this culture. Data obtained for the disintegration in conductivity experiments were found in good correlation with direct counting of yeast lethality using light microscopy. The PEF-induced lethality of the yeast cells and size flocs increased with the mixing of suspensions and the increase of temperature.
authors.affiliation: Chemical Engineering Department CNRS UMR 6067, Université de Technologie de Compiègne, Centre de Recherche de Royallieu, BP 20529, 60205 Compiègne, France.
authors.forename: H
authors.initials: H
authors.lastname: El Zakhem
authors.forename: J-L
authors.initials: JL
authors.lastname: Lanoisellé
authors.forename: N I
authors.initials: NI
authors.lastname: Lebovka
authors.forename: M
authors.initials: M
authors.lastname: Nonus
authors.forename: E
authors.initials: E
authors.lastname: Vorobiev
mesh_terms: D003102:Colloids / Q000737:chemistry*; D004553:Electric Conductivity; D008970:Molecular Weight; D010316:Particle Size; D012441:Saccharomyces cerevisiae / Q000737:chemistry* / Q000166:cytology; D055672:Static Electricity; D013696:Temperature; D014867:Water / Q000737:chemistry
chemical_list: D003102:Colloids; D014867:Water