European survey and evaluation of sampling methods recommended by the standard EN ISO 18593 for the detection of Listeria monocytogenes and Pseudomonas fluorescens on industrial surfaces

Abstract

The ready-to-eat products can be contaminated during processing by pathogen or spoilage bacteria, which persist in the industrial environment. Some bacterial species are able to form biofilms which protect them from environmental conditions. To check the bacterial contamination of the surfaces in the food industries, the professionals must regularly use surface sampling methods to detect the pathogen such as Listeria monocytogenes or the spoilage such as Pseudomonas fluorescens. In 2010, we designed and carried out a European survey to collect surface sampling information to detect or enumerate L. monocytogenes in food processing plants. A total of 137 questionnaires from 14 European Union Member States were returned. The outcome of this survey showed that the professionals preferred friction sampling methods with gauze pad, swab and sponges versus contact sampling methods. After this survey, we compared the effectiveness of these three friction sampling methods and the contact plates, as recommended in the standard EN ISO 18593 that was revised in 2018, on the recovery of L. monocytogenes and of P. fluorescens in mono-specie biofilms. This study showed no significant difference between the effectiveness of the four sampling methods to detach the viable and culturable bacterial population of theses mono-specie biofilms.

Monitoring by a Sensitive Liquid-Based Sampling Strategy Reveals a Considerable Reduction of Listeria monocytogenes in Smeared Cheese Production over 10 Years of Testing in Austria

“…Preventing foodborne hazards along the food processing chain is supported by an intelligent sampling strategy that may differ among food sectors and professionals. For L. monocytogenes environmental testing, mostly swab and sponge-based friction sampling methods are used [ 54 ]. The decrease in the L. monocytogenes detection rate, as seen in Austrian cheese factories in recent years, coincides with an increased understanding and acceptance of food safety parameters by the cheese producers, which was in part contributed to by a high-profile cheese-borne outbreak of listeriosis [ 55 ].…”

Optimization of a Method for the Concentration of Genetic Material in Bacterial and Fungal Communities on Fresh Apple Peel Surfaces

“…Surface swabbing is a method primarily used in the evaluation of microbial loads on food contact surfaces and does not consistently recover microorganisms when present at low concentrations and across product types [ 78 ]. A recent survey evaluating the preference and efficacy of friction-based surface swabs compared to other contact methods showed no difference in their ability to remove bacterial populations from food-processing plant surfaces, which also suggests that friction alone is unable to yield better results than low-contact alternatives, even when populations are highly concentrated [ 79 ]. This method may be improved upon by a hurdle approach, as evaluated by Branck et al (2017), who described the efficacy of traditional surface swabbing compared to a sonicated swab in L. monocytogenes biofilms on stainless steel coupons [ 80 ].…”

Effectiveness of a Self-Decontaminating Coating Containing Usnic Acid in Reducing Environmental Microbial Load in Tertiary-Care Hospitals

“…Samples from Hospital A were transferred to the Aeginition Hospital Department of Biopathology (University of Athens Medical School) for testing, according to reference [ 30 ]. In particular, bacteria and fungi were identified with aMicroScan autoSCAN-4 System, Beckman Coulter.…”