Isolation and identification of adherent gram-negative microorganisms from four meat-processing facilities

Abstract

Biofilms are described as a matrix of microorganisms which have adhered to and colonized a surface. Once formed, biofilms are difficult to remove and may be a source of contamination in food-processing environments. In this study, stainless-steel chips were fixed to surfaces adjacent to food-contact surfaces and cast-iron chips were suspended in the floor drains of four meat-processing plants. Biofilm formation was quantified by staining the attached cells and viewing them under epifluorescence microscopy. The stainless-steel and cast-iron chips removed from the plant environment showed some attached microorganisms. Floor drains appeared to provide an excellent environment for the formation of biofilms. Pseudomonas, Klebsiella, Aeromonas, and Hafnia species were identified as gram-negative microorganisms associated with the test surfaces.