EN
The objective of the study was to investigate elimination of selected Gram-negative bacteria (Salmonella enterica ssp. enterica sv. Anatum, Escherichia coli, Proteus sp., and Pseudomonas fluorescens) from the surface of chicken wing skin after ultrasound treatment in water and in 1% aqueous lactic acid solution. Samples were intentionally infected with the bacterial strains and then treated with ultrasound at a frequency of 40 kHz and an intensity of 2.5 W/cm² for 3 or 6 min. The degree of reduction of bacteria depended on the duration of ultrasound treatment and the kind of liquid. Sonication in water for 3 min resulted in a reduction of the number of microorganisms on the skin surface to 1.0 log CFU/cm² but longer treatment (6 min) resulted in a reduction of over 1.0 log CFU/cm². The most sensitive was E. coli. Sonication in the lactic acid aqueous solution for 3 min reduced the number of the bacteria by more than 1 log CFU/cm² and after 6 min, the reduction exceeded 1.5 log CFU/cm² (up to 4.0 log CFU/cm²). The bacterium most sensitive to sonication in lactic acid was Pseudomonas. Ultrasound treatment in combination with a lactic acid can be a suitable method for decontamination of poultry carcass skin.