Carolina Ripolles-Avila, A.S.Hascöet, J.J.Rodríguez-Jerez
Cleaning and disinfection procedures are critical and must be performedto established guidelines otherwise they potentially allow cross-contaminationto occur, which not only reduces a product's shelf-lifebut also increases the risk of foodborne diseases related to the presenceof pathogens (Moore & Griffith, 2002; Reij& Den Aantrekker, 2004). Asurveillance programme to control foodborne infections and intoxicationsin Europe reported that the main contributing factor to outbreakswas cross-contamination (Tirado & Schmidt, 2001), indicating thatenormous efforts must be made to control this otherwise it could becomean increasing tendency over time(Giaouris et al., 2014). Listeria monocytogenes is a foodborne pathogen that is considerablysignificant for the food industry (Jemmi& Stephan, 2006; Larsen et al.,2014; Ripolles-Avila et al.,2018; Todd &Notermans, 2011). For instance, listeriosis is the onlyfoodborne disease that has shown a notable increasing tendency in theEU/EEA over the last 5 years (2012–2016), with a 9.3% increment inconfirmed cases between 2015 and 2016 (EFSA-ECDC, 2017).Although this percentage of cases may seem low compared toother pathogens, its high mortality rate amongst human populationswith vulnerable immune systems, the elderly and its connection withstillbirth and miscarriage makes it a considerable public health issue(Lourenço et al., 2012).Surface sampling is absolutely essential forevaluating and controlling the microbial contamination of food contactsurfaces. Surface sampling techniques have until now been based onswabs or sponges and consist of extracting the microorganisms from thesurface and contact plates (Kasuga et al., 2011; Valentine et al., 2008).However, these traditional methods can present some standardizationproblems when collecting samples from the different surfaces found inthe food industry. With the goal of overcoming these standardizationproblems, a surface sensor named SCH (Hygiene Control Sensor, Premiumlab)was developed to monitor the biological contamination ofsurfaces and offer an alternative to traditional methods when analyzing product safety and quality (Ripolles-Avila et al., 2018).When using these sensors, the microorganisms present onthe surfaces must be recovered(González-Rivas et al., 2018; Ripolles-Avila et al., 2019). The main aim of the present study was toimplement and assess this novel technology to evaluate the microbiologicalcontamination of surfaces. For that, different industrial surfaces in ameat processing plant were evaluated through implementing the sensor-based sampling system, with a focus on detecting L. monocytogenes. The results obtained showed that the areas considered as major contributors to microbial contamination were three of the sampledfloors and the storage cabinet for tools, demonstrating to be important sources of possible cross-contamination. Atotal of four L. monocytogenes presences were obtained during sampling. A direct relation was observedbetween aerobic counts and detecting L. monocytogenes, and three possible hypotheses were formulated toexplain the connection. Last, a safety zone marking the limits beyond which the surface can be considered as asafety risk was established. The use of SCH sensors as a surface sampling system for the food industry havebeen shown to work effectively and with relative ease.