COMPORTAMENTO DI LISTERIA MONOCYTOGENES IN INSALATA DI POLPO E PATATE

Octopus and potato salad was artificially contaminated with a L. monocytogenes suspension (mix of three different strains), packaged and stored at different temperatures 5°, 10°, 15° and 20°C for several days. This food didn't support the grow of Listeria: in fact during the shelf-life period we observed microorganism decreasing with a speed directly correlated to storage temperature increasing. As a consequence, a batch of octopus and potato salad respecting the critical limit for L. monocytogenes established by European regulation for ready-to-eat foods (< 100 cfu/g) can be considered safe beyond the end of shelf-life period fixed by the producer (9 days) not only at optimal storage conditions but also at domestic storage conditions or even in situation of thermal abuse.