Survival of Listeria monocytogenes in low acid italian sausage produced under brazilian conditions

Abstract

Dry sausages have been considered ready-to-eat products with low risk of causing listeriosis due to the hurdles created during the manufacturing process such as low pH and aw, high salt concentration and presence of lactic acid bacteria (LAB). However, several studies have detected survival of Listeria monocytogenes in these products and also shown that process parameters, LAB and L. monocytogenes strains directly influence the results. In this work, survival of the pathogen in sausages prepared with three different formulations (one standard formulation, one formulation added of Lactobacillus plantarum and one added of 2% sodium lactate), using the manufacturing process usually employed in Brazil, was evaluated. Naturally contaminated sausages presented a small increase in the counts of L. monocytogenes in the first days of the process, followed by a gradual decrease until the end of the process. In experimentally contaminated samples containing L. plantarum, the reduction of counts of L. monocytogenes during processing was considerable, but there wasn´t significant differences between the treatments.

Evaluation of the Listeria monocytogenes inactivation during post-process storage of fermented sausages: A basis for the development of a decision support tool

“…1). This is in agreement with published works investigating the in situ nonthermal inactivation of the pathogen during manufacturing of fermented sausages (Degenhardt & Sant' Anna, 2007;Drosinos et al, 2006;Gareis, Kabisch, Pichner, & Hechelmann, 2012;Mataragas, Bellio, Rovetto, Astegiano, Decastelli, et al, 2014;Submitted for publication;Mataragas, Bellio, Rovetto, Astegiano, Greci, et al, 2015). In those studies the inactivation curve varies between linear and various shapes of a non linear pattern indicating the potential presence of a more resistant subpopulation due to stress adaptation.…”

Management of Listeria monocytogenes in fermented sausages using the Food Safety Objective concept underpinned by stochastic modeling and meta-analysis

“…Evidence for the L. monocytogenes inactivation during production and cold storage of fermented sausages has been documented (Byelashov et al, 2009;Degenhardt and Sant' Anna, 2007;Drosinos et al, 2006;Farber et al, 1993;Foegeding et al, 1992;Gareis et al, 2012;Gounadaki et al, 2007;Lahti et al, 2001;Mataragas et al, 2015aMataragas et al, , 2015bMataragas et al, , 2015cMataragas et al, , 2015dPorto-Fett et al, 2008;Simpson et al, 2008;Thevenot et al, 2005) and the meta-analysis confirmed this effect, but it provided also a quantitative estimation of the overall effect of these processes on L. monocytogenes survival in the fermented sausages. Meta-analysis is a powerful statistical method analyzing a relatively large amount of data from different individual studies with different experimental designs to produce a more precise with greater statistical power estimate of a particular intervention/treatment or to identify sources of variation (Gonzales-Barron et al, 2008).…”

Quantitative microbial risk assessment of Salmonella in dry fermented sausage (salami) in Southern Brazil

“…This represents the best scenario (baseline) for sausage production characterized by good raw material pH and a w values and optimal fermentation. Degenhardt and Sant'anna (2007a); Cirolini et al (2010) .…”

“…During maturation, the fermentation and drying conditions vary depending on the product quality and the culture ( Degenhardt and Sant'anna, 2007a;Hutkins, 2006 ). The fermentation and drying conditions applied here were 72 h at 24 °C, 72 hours at 20 °C and 18 days of drying at 14 °C, resulting in 24 days of maturation in total.…”