Dezincification inhibition of a food processing brass OT60 in presence of Pseudomonas fluorescens

Commercial brass OT60 is commonly used for food processing. The inhibition of its dezincification in presence of the biofilm forming Pseudomonas fluorescens was documented in this work. Electrochemical polarizations, Electrochemical Impedance Spectroscopy and post treatment analyses were carried out during 120 h of immersion in presence of bacteria vs a sterile condition in 0.1 M NaCl. The presence of bacteria decreases the oxygen availability, strongly influencing the formation and the nature of superficial oxides. The biofilm promotes a uniform growth of Zn oxides and hydroxides, inhibiting the re-deposition of copper and preventing the acceleration of the anodic reaction.