Application of isolated Lactobacillus sakei and Staphylococcus xylosus strains as a probiotic starter culture during the industrial manufacture of Tunisian dry‐fermented sausages

Abstract

For decades, lactic acid bacteria has been isolated and selected to be used as starter cultures in meat fermentation for standardization and management of quality of dry‐fermented sausage which constitute a considerable challenge. The aim of this study was to evaluate the effect of Lactobacillus sakei strains, isolated from different origins, on qualities of dry‐fermented sausages. These last, manufactured with different combinations of starter cultures (L. sakei + Staphylococcus xylosus), were ripened, using the same raw materials and conditions, for 45 days. Samples were collected during this period, and microbiological, physicochemical, fatty acid profile, and sensorial analyses determined. Lactic acid bacteria were the dominant flora during ripening. A desirable PUFA/SFA ratio, corresponding to 1:1.7 (0.6), was detected after 24 days of maturation in sausages inoculated by L. sakei BMG 95 and S. xylosus. Sensory analysis showed that fermented sausages manufactured with L. sakei and S. xylosus had a more desirable odor, flavor, and texture and consequently were preferred overall. In particular, sensory panellists preferred sausages produced with either L. sakei 23K or L. sakei BMG 95 when compared to fermented sausage produced with a commercial starter or no starter at all.

Effect of the Dry-Cured Fermented Sausage “Salchichón” Processing with a Selected Lactobacillus sakei in Listeria monocytogenes and Microbial Population

“…No differences for moisture content or a w parameters were observed between both cases. This evidences that L. sakei 205 does not provoke any modification in any of the two above-mentioned parameters, as has been reported for other LAB assayed [ 41 , 42 ]. However, the strain L. sakei 205 provoked a slight reduction in pH in the first 30 days of ripening, in comparison with uninoculated control, probably due to the increase in the lactic acid content, as a result of carbohydrate breakdown by microbial metabolism [ 43 ].…”

Effect of inoculating Lactobacillus sakei strains alone or together with Staphylococcus xylosus on microbiological, physicochemical, fatty acid profile, and sensory quality of Tunisian dry‐fermented sausage

“…Microbiological analysis was performed according to the International Standards Organization (ISO), “Association Française de Normalisation” (AFNOR and “Norme Française” (NF) norms as described by Najjari et al. (2020). Briefly, 25 grams of each sample were suspended aseptically in 225 ml of salt peptone water (Scharlau Chemie, S.A) and homogenized, and serial dilutions of 1 or 0.1 ml were poured or spread on agar plates.…”

“…Several physicochemical parameters were monitored during the ripening process of sausages to know: pH, water activity ( a w ), and moisture as described by Najjari et al. (2020).…”

“…Lipids extraction from sausages was performed, according to the NF V 04‐402 method, for the quantification and characterization of fatty acids by gas phase chromatography (CPG) after conversion to their methyl esters (ISO 5509‐1978) (Najjari et al., 2020).…”

“…Here, we reported, for the first time, novel microbiological, physicochemical, nutritional, and sensorial measurements of Tunisian dry‐fermented sausages inoculated with L. sakei F and L. sakei 23K, individually, to determine their potentials as starter cultures. Indeed, in our previous study, the analysis was performed in a different batches and periods (several months between the two industrial productions) on Tunisian dry‐fermented sausages inoculated only with a mixed cultures of L. sakei strains + S. xylosus (Najjari et al., 2020).…”