Autochthonous lactic acid bacteria from Kaddid as functional starter culture to improve quality and safety
摘要
Lactic acid bacteria (LAB) from meat dry-salted Kaddid were evaluated using spoilage and safety criteria as a first step of multivariable selection. LAB were isolated, identified and characterized from Kaddid prepared under controlled conditions. After preliminary physiological characterization, isolates (n = 39) were subjected to (GTG)5-PCR analysis and 16S rRNA sequencing. Major LAB populations were, Lactiplantibacillus paraplantarum (41%), Latilactobacillus sakei/subsp. sakei (25%), Enterococcus faecium (13%), Pediococcus acidilactici (10%), Enterococcus hirae (6%) and Weissella cibaria (5%). Antagonistic activity against pathogens/contaminants and yeast/molds showed strains with antilisterial and antifungal activity. Bacteriocin-like inhibitory substances (BLIS) showed high titles (AU/mL) against Listeria (L.) monocytogenes FBUNT. The examination of bacteriocin genes revealed Lpb. paraplantarum K18, Lat. sakei K25 and Lat. sakei subsp. sakei K22, K26 strains harboring skgA and sakP structural genes encoding for sakacin G and P bacteriocins. Resistance/susceptibility of lactobacilli strains to antibiotics showed high phenotypic resistance to tetracycline (TET) while multi-resistance pattern was displayed by enterococci. Genotypic characterization exhibited only tetM out of 15 assayed genes, conferring resistance to TET. As a quality criterion, no exopolysaccharides and biogenic amines production were detected in the evaluated strains. Based on these results, Lpb. paraplantarum K18 strain, with inhibitory and antifungal activities, phenotypical susceptibility to the assayed antimicrobial compounds and low risk as spoilers, could be used as functional starter cultures for safe fermented meat production.