The low power of the ultrasonic bath used and non-antimicrobial marinade solution were likely responsible for the findings. Kordowska-Water and Stasiak (2011) investigated the removal of Gram-negative bacteria (Salmonella anatum, E. coli, Proteus sp. and Pseudomonas fluorescens) from the surface of chicken skin after treatment with ultrasound (40 kHz and 2.5Wcm−2 for 3 or 6 min) in water and in aqueous 1% lactic acid.