title: Native microflora in fresh-cut produce processing plants and their potentials for biofilm formation.
abstract: Representative food contact and nonfood contact surfaces in two mid-sized, fresh-cut processing facilities were sampled for microbiological analyses after routine daily sanitization. Mesophilic and psychrotrophic bacteria on the sampled surfaces were isolated by plating on nonselective bacterial media. Alternatively, bacteria were isolated after an incubation period that allowed the formation of heterogeneous biofilms on stainless steel beads. Of over 1,000 tested isolates, most were capable of forming biofilms, with approximately 30 % being strong or moderate biofilm formers. Selected isolates (117) were subjected to species identification by using the Biolog Gen III microbial identification system. They distributed among 23 genera, which included soil bacteria, plant-related bacteria, coliforms, and opportunistic plant- or human-pathogenic bacteria. The most commonly identified bacteria species were Pseudomonas fluorescens, Rahnella aquatilis, and Ralstonia insidiosa. The high prevalence of R. insidiosa, a strong biofilm former, and P. fluorescens, a moderate biofilm former, suggests that they were established residents in the sampled plants. These results suggest that native microflora capable of forming biofilms are widely distributed in fresh-produce processing environments.
authors: Department of Nutrition and Food Science, University of Maryland, College Park, Maryland 20740, USA.
authors: Nancy T
authors: NT
authors: Liu
authors: Alan M
authors: AM
authors: Lefcourt
authors: Xiangwu
authors: X
authors: Nou
authors: Daniel R
authors: DR
authors: Shelton
authors: Guodong
authors: G
authors: Zhang
authors: Y Martin
authors: YM
authors: Lo
mesh_terms: D001419:Bacteria / Q000302:isolation & purification; D001422:Bacterial Adhesion / Q000502:physiology*; D018407:Bacterial Physiological Phenomena; D018441:Biofilms / Q000254:growth & development; D015169:Colony Count, Microbial; D003257:Consumer Product Safety; D004783:Environmental Microbiology; D005506:Food Contamination / Q000032:analysis / Q000517:prevention & control; D005511:Food Handling / Q000379:methods*; D005516:Food Microbiology; D005525:Food-Processing Industry; D005638:Fruit / Q000382:microbiology; D006801:Humans; D011551:Pseudomonas fluorescens / Q000302:isolation & purification / Q000502:physiology; D013193:Stainless Steel; D014675:Vegetables / Q000382:microbiology
chemical_list: D013193:Stainless Steel