High hydrostatic pressure processing of sliced fermented sausages: A quantitative exposure assessment for Listeria monocytogenes. (March 2019)

• Record Type: Journal Article
• Authors: Possas, Arícia; Valdramidis, Vasilis; García-Gimeno, Rosa María; Pérez-Rodríguez, Fernando
• Is Part Of: Innovative food science & emerging technologies. Volume 52(2019)
• Page Start: 406
• Page End: 419
• Publication Date: 2019-03
• Subjects: Probabilistic model -- Cross-contamination -- High-pressure -- Risk assessment -- Ready-to-eat meat -- Nitrite reduction; Food -- Biotechnology -- Periodicals; Food industry and trade -- Technological innovations -- Periodicals; Aliments -- Biotechnologie -- Périodiques; Food -- Biotechnology; Periodicals; Electronic journals; 664.005
• DOI: 10.1016/j.ifset.2019.01.017
• Languages: English
• ISSNs: 1466-8564

Abstract

Abstract: Fermented sausages have traditionally been considered to be safe products from a microbiological point of view, mainly due to nitrite addition, their low a w and reduced pH. However, post-process contamination during slicing and packaging operations may increase microbial concentration and prevalence on final products. A stochastic simulation modelling approach was conducted to determine the extent of Listeria monocytogenes survival on sliced chorizo submitted or not to high hydrostatic pressure (HHP) treatments after post-process contamination ( i.e., cross-contamination during slicing). A probabilistic model comprising nine steps from mixing of raw materials to consumption was constructed. The effects of various initial levels of L. monocytogenes in the meat batter (−1.43–3 log cfu/g), HHP treatments (400–600 MPa/18 °C for 0–12 min) and nitrite concentrations (0–150 ppm) on L. monocytogenes distribution were assessed by means of the application of predictive models, literature information and data obtained experimentally. Once implemented, the probabilistic model was simulated by using Monte Carlo analysis. The probability distribution of L. monocytogenes contamination levels was determined for various scenarios. Model outputs showed that cross-contamination during slicing was an important source contributing to increase pathogen prevalence and concentration on final products, with transferred levels equal to 0.59 ± 0.48 log cfu/g. Under all simulated scenarios, formulation and storage conditions, the level of L. monocytogenes on sliced vacuum-packed chorizo at the consumption phase was estimated to be lower than 100 cfu/g and pressure treatments at 600 MPa for 10–12 min would result in non-contaminated packs. Overall, the probabilistic model developed in this study from raw material reception up to the end of the shelf-life ( i.e., 90 days) of sliced fermented sausages is proposed as a suitable tool to determine combinations of HHP treatments and nitrite concentrations ensuring the compliance with microbiological criteria. Highlights: A probabilistic model of L. monocytogenes in sliced vacuum-packed chorizo was built. Predictive microbiology models were integrated into the quantitative exposure assessment. HHP treatments reduce pathogen level and prevalence in products, assuring compliance with microbiological criteria. Nitrite reduction does not affect the microbiological safety concerning L. monocytogenes when products are submitted to HHP.