Characteristics of an environmental strain, Enterococcus faecalis CECT7121, and its effects as additive on craft dry-fermented sausages

• Published in: Food microbiology Vol. 25; no. 4; pp. 607 - 615
• Main Authors: Sparo, M., Nuñez, G.G., Castro, M., Calcagno, M.L., García Allende, M.A., Ceci, M., Najle, R., Manghi, M.
• Format: Journal Article
• Language: English
• Published: London Elsevier Ltd 01.06.2008; Elsevier
• Subjects: antibacterial properties; bacterial contamination; Bacteriocins - pharmacology; beta-Lactamases - metabolism; Biogenic Amines - analysis; Biological and medical sciences; Biopreservation; Colony Count, Microbial; Consumer Product Safety; dried meat; Drug Resistance, Bacterial - drug effects; Dry-fermented sausages; E. faecalis; Enterobacteriaceae; Enterococcus faecalis; Enterococcus faecalis - genetics; Enterococcus faecalis - isolation & purification; fermented foods; Food Additives; food biopreservation; food biopreservatives; Food industries; Food microbiology; food pathogens; Food Preservatives; Fundamental and applied biological sciences. Psychology; Gelatinases - genetics; Gram-positive bacteria; Gram-Positive Cocci - isolation & purification; Hemolysin Proteins - genetics; Hydrogen-Ion Concentration; lactic acid; Lactic Acid - metabolism; lactic acid bacteria; Lactobacillus; Lactobacillus - isolation & purification; Lipase - metabolism; Listeria monocytogenes; Meat and meat product industries; Meat Products - microbiology; plate count; Probiotics - pharmacology; Quality Control; Random Amplified Polymorphic DNA Technique; sausages; sensory evaluation; sensory properties; Staphylococcus aureus; Staphylococcus aureus - isolation & purification; Dry-fermented sausages; Biopreservation; E. faecalis; Enterococcus faecalis; Meat product; Pork product; Fermented product; Strain; Streptococcaceae; Additive; Dry sausage; Bacteria; Micrococcales
• ISSN: 0740-0020; 1095-9998
• DOI: 10.1016/j.fm.2008.01.008

Lactic acid bacteria are the most adequate microorganisms for natural preservation of food. In the present work, the strain of Enterococcus faecalis CECT7121 was employed in the manufacture of craft dry-fermented sausages and its performance as a biopreservative was analysed. This strain is devoid of the genes for haemolysin and gelatinase and does not produce biogenic amines. It is sensitive to almost all the antibiotics tested and opsonophagocytic assays showed that it is devoid of a capsule. This strain had a high LD50 (10 11 CFU ml −1) in mice. No statistical differences were found between control and sausages inoculated with E. faecalis CECT7121 regarding the production of lactic acid, pH variation over time, reaching a minimum pH value of 5.1, and sensory analysis in both series. Sausages inoculated with E. faecalis CECT7121 had lower viable counts of Enterobacteriaceae, Staphylococcus aureus and other Gram-positive cocci at the end of fermentation and 7 days and no viable enterobacteria and S. aureus were recovered at the end of drying. E. faecalis CECT7121 did not affect the growth of Lactobacillus spp. but it displaced the autochthonous populations of enterococci. E. faecalis CECT7121 was recovered in each time point as assessed by its inhibitory activity on Listeria monocytogenes and S. aureus. These results would indicate that the addition of E. faecalis CECT7121 during the manufacture of craft dry-fermented sausages offers an interesting alternative for biopreservation.