**4. The occurrence of** *L. monocytogenes* **in the food processing environment**

*L. monocytogenes* is able to attach to food processing surfaces and multiply to form biofilms in inaccessible locations in processing facilities [9]. Biofilms protect the bacterium against antimicrobial action, enabling it to colonize food processing equipment, conveyor belts, pipes, floors and drainage systems and to persist for months or even years, cross-contaminating different surfaces in food processing plants [26]. The formation of biofilms on various food contact surfaces by *L. monocytogenes* makes it extremely difficult to control this pathogen effectively, especially in processing plants where inadequate cleaning has been carried out [27].

been found in raw and processed RTE foods that required low temperature storage [35]. The high volume of food products such as meat, vegetables, dairy products and fruits that pass through the cold chain in food service establishments could contribute to the high incidence

Meat Processed meat products such as ground beef, sausages, deli ham, beef hot dogs and meat-

Contamination, Prevention and Control of *Listeria monocytogenes* in Food Processing and Food…

http://dx.doi.org/10.5772/intechopen.76132

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Poultry Processed chicken such as deli chicken, deli turkey, eggs, and related sandwich products Fish Cooked shrimps, sushi, smoked salmon, seafoods, and related sandwich and salad dishes

Fruit and vegetables Cabbage, lettuce, cucumber, frozen green beans, peanut butter, vegetable salads, raw sprouts, cantaloupe melon and related salad dishes

**Table 2.** Listeria in food: foods that are susceptible to contamination by *Listeria monocytogenes* [57, 74].

related sandwich products (e.g., pork, beef)

Inadequate cleaning procedures and hygiene practices can promote the formation of biofilms on food contact surfaces in food service establishments, thereby increasing the chances of *L. monocytogenes* cross-contamination within food service facilities [37]. Because biofilms are able to resist most sanitisers and disinfectants used, cross-contamination by *L. monocytogenes* poses a serious food safety risk in food service establishments, including domestic kitchens [38]. The ease with which *L. monocytogenes* is able to adhere to food contact surfaces and form biofilms increases the likelihood of its persisting on food contact surfaces, and hence crosscontaminating the final food products [39, 40]. The presence of food debris on food contact

of *L. monocytogenes* in RTE food and on food contact surfaces [34, 36].

Pasta, cakes, pies, sausage rolls

**Food groups Susceptible food products**

Dairy Cheese, yogurt

Cereal and baked products

surfaces encourages the formation of *L. monocytogenes* biofilms [41].

**domestic kitchens**

**6. The occurrence of** *L. monocytogenes* **on food contact surfaces in** 

Inadequate hygiene practices in domestic kitchens may contribute to the persistence of foodborne pathogens, thereby compromising the safety of foods produced there [42]. Home kitchens have been found to be a significant location where food-borne illnesses are acquired. A survey conducted in the domestic kitchens of consumers aged 60 and above in the UK indicated that a large number of foods in home refrigerators were beyond the use-by date and up to 66% of opened RTE foods had been stored beyond the recommended 2 days after opening [43]. A study of the occurrence of *Listeria* spp. on food contact surfaces in domestic kitchens in the Netherlands found high levels of *L. monocytogenes* on dish-cloths and in bathrooms, but low levels on kitchen sinks, washing-up brushes and refrigerators [44]. Many researchers have found high levels of *L. monocytogenes* on refrigerator surfaces in domestic kitchens [45].
