## 4 Discussion  
Microbiological contamination is distributed throughout the food processing chain, from its production to consumption. The risks are greater in foods, which do not require further heating before consumption, such as ready to eat (RTE) products. Moreover, low hygiene practices during handling, cross- contamination and poor refrigerated temperature control may be responsible for exposure to pathogens bacteria through the food chain. The  
Figure 4: Gelatinase test results. Figure 3: Haemolysis test results. Figure 2: (a,b) Haemolysis and gelatinase test results for all tested strains. European Food Safety Authority believes that up to 90% of listeriosis cases occurring from 2008 to 2015 are due to the consumption of RTE foods, such as smoked fish, preserved meat and cheeses, and also vegetables, such as ready to eat salads. A third of the cases was due to the proliferation of _Listeria_ spp., _Staphylococcus_ spp., _Shigella, Y. enterocolitia_ and other pathogenic bacteria found in foods incorrectly stored in the refrigerated vending machine [25; 26; 27]. The present study showed that among the 54 isolates, 25 strains (46.3%) belonged to harmless microorganisms, including _Leuconstoc_ and _Lactococcus_, lactobacilli used as starters in fermentation processes of cheese or bread, whereas the remaining 27 strains (53.7%) belonged to pathogenic bacteria (13 _S. aureus_, 5 _Listeria_ spp., 4 _Enterococcus_ spp., 4 _Acinetobacter_ spp., one _Y. enterocolitia_, one _A. hydrophilis_, and one _Citrobacter_ spp.). The pathogens present in some samples were frequently found with a microbial load exceeding the limits of the EC Regulation 2073/2005 [28], as in the case of the eight samples contaminated with _S. aureus_ only. In other studies _S. aureus_ was found in RTE products, especially in cold served salads and sandwic [29; 30], tracing its presence in ingredients, such as vegetables and/or fruit and products of animal origin (meat, sausages) [31]. _S. aureus_, by the production of a thermostable toxin, is the species most frequently responsible for food poisoning (the third pathogen for food-borne diseases). _S. aureus_ poisoning is a pathology of a modest clinical entity but has a strong socio-economic impact as it is highly widespread. In the present investigation some samples were contaminated by two or more pathogenic bacteria at the same time. Sample 3, a product characterized by many components and therefore subjected to multiple manipulations, showed the presence not only of _S. aureus_, but also of _L. ivanovii_ and _Citrobacter_ spp. In sample 6, a shrimp-based product, both _Y. enterocolitia_ and _L. ivanovii_ were isolated. _L. ivanovii_ was recently associated with sporadic human infections, although it is usually linked to animal infections, in particular ruminants, and this microorganism is known as a milk and cheese contaminant [32]. _Citrobacter_ species, belonging to the _Enterobacteriaceae_ family, are considered opportunistic pathogens for humans, but for their wide distribution in the environment and intestinal tracts, they have the capability to be transferred from the farm to fresh produce destined for consumption, thereby constituting a public health risk [33]. Yersiniosis is the third most commonly reported zoonosis in Europe, mainly for the consumption of pig meat and products thereof [25]. In some European countries _Y. enterocolitia_, the dominating species among human diseases is a more significant concern than _Salmonella_ because it can grow at refrigeration temperature [34]. As a psychotrophic microorganism, a significant health threat is posed by refrigerated products where this pathogen, as well as _Listeria_ and _Aeromonas_, can proliferate. _A. hydrophilis_ is a microorganism found in water, considered the most important infectious reservoir [35], and consequently, it is mainly isolated from seafod and vegetables. It rarely causes food outbreaks, the most recent reported in Sweden and Norway [36]. _Acinetobacter_ is rarely associated with diarrheal disease but _A.