Antimicrobial effects of treated olive mill waste on foodborne pathogens

This work assesses the in vitro antimicrobial activity of an aqueous olive mill waste extract (AE-2) on growth diverse cocktails foodborne pathogens species (Listeria monocytogenes, Staphylococcus aureus, Escherichia coli, and Salmonella Enterica). The effects were evaluated by Response Surface Methodology, using a two-block (D-optimal full factorial) sequential design, with two independent variables (hydroxytyrosol concentration 0–3000 ppm pH 3.5–6.5) percentage inhibition (%I) as dependent variable. S. Enterica E. coli behaviours similar but different from L. monocytogenes aureus. models predicted complete four pathogen region defined 3.80–3.87 1200–1314 hydroxytyrosol. Within experimental region, model showed best predictions for worst Enterica, errors never exceeded 46%. study could promote use by-products natural preservatives food industry, especially acidic matrices.