Assessing the Impact of Different Technological Strategies on the Fate of Salmonella in Chicken Dry-Fermented Sausages by Means of Challenge Testing and Predictive Models

Salmonella is the main relevant pathogen in chicken dry-fermented sausages (DFS). The safety of shelf-stable DFS must rely on the production process, which should not only prevent growth but promote inactivation of Salmonella. The aim of the study was to assess the behaviour of Salmonella during the production process of two types of low-acid chicken DFS. The impact of the use of starter culture, corrective storage and high-pressure processing (HPP) at different processing times was assessed through challenge testing, i.e., inoculating a cocktail of Salmonella into the meat batter (at 6 Log(10) cfu/g) used for sausage manufacture. Sausages of medium (fuet-type, FT) and small (snack-type, ST) calibre were elaborated through ripening (10-15 degrees C/16 d) and fermentation plus ripening (22 degrees C/3 d + 14 degrees C/7 d). Physico-chemical parameters were analysed and Salmonella was enumerated throughout the study. The observed results were compared with the simulations provided by predictive models available in the literature. In FT, a slight decrease in Salmonella was observed during the production process while in ST, a 0.9-1.4 Log(10) increase occurred during the fermentation at 22 degrees C. Accordingly, DFS safety has to be based on the process temperature and water activity decrease, these factors can be used as inputs of predictive models based on the gamma-concept, as useful decision support tool for producers. Salmonella lethality was enhanced by combining HPP and corrective storage strategies, achieving >1 and 4 Log(10) reductions for FT and ST, respectively.

Automated summary

The behavior of Salmonella during the production process of low-acid chicken dry-fermented sausages was assessed. The impact of different processing times, such as the use of starter culture, corrective storage, and high-pressure processing (HPP), was evaluated. The safety of the sausages relied on the decrease in Salmonella counts through the process, and predictive models based on the gamma-concept could be used as decision support tools for producers. Combining HPP and corrective storage strategies enhanced Salmonella lethality.