Dynamics of Microbial Communities in Nitrite-Free and Nutritionally Improved Dry Fermented Sausages

Dry fermented sausage innovation trends are linked to consumer preferences for clean label and sodium-reduced foods. This study aims to evaluate the effect of the formulation and production process temperature on the dynamics of bacterial communities in fuet-type dry fermented sausages using metataxonomics. Six fuet batches were manufactured, including formulations without and with the addition of nitrifying salts (replaced or not by pork liver auto-hydrolysate as a colouring agent), processed at 3 to 12 degrees C, and a partial replacement of NaCl by KCl, processed at 12 degrees C. Fermentation was performed spontaneously or by a starter culture. Physicochemical characterisation and culture-dependent and independent bacterial analyses were performed at day 0, 4 and 12, at the end of ripening (a(w) < 0.90) and after storage. Temperature was the most important factor determining the change in pH, a(w) and lactic acid bacteria levels while the presence of a starter culture promoted a pH decrease. Metataxonomic analysis showed that low temperature processes and the absence of nitrifying salts allowed the growth of spoilage-related species, while sausages submitted to a mild temperature containing a starter culture and nitrifying salts showed less bacterial diversity. Liver auto-hydrolysate added putative probiotic species to the product. This study provides valuable information to manufacturers who want to innovate safely.

Automated summary

The effect of formulation and production process temperature on bacterial communities in fuet-type dry fermented sausages was evaluated using metataxonomics. The results showed that temperature was the most important factor determining changes in pH, water activity, and lactic acid bacteria levels. The presence of a starter culture promoted a decrease in pH. Low temperature processes and the absence of nitrifying salts allowed the growth of spoilage-related species, while sausages with mild temperature, a starter culture, and nitrifying salts showed less bacterial diversity.