Bio-preservation of ground beef meat by Enterococcus faecalis CECT7121

Area of Science:

• Food Microbiology
• Probiotics and Food Safety
• Bacteriology

Background:

• Ground beef is a common source of foodborne illnesses.
• Pathogenic bacteria such as Escherichia coli O157:H7, Staphylococcus aureus, Clostridium perfringens, and Listeria monocytogenes pose significant food safety risks.
• Probiotics offer a potential natural solution for controlling microbial contamination in food products.

Purpose of the Study:

• To evaluate the bactericidal efficacy of the probiotic Enterococcus faecalis CECT7121.
• To determine the effectiveness of E. faecalis CECT7121 against key foodborne pathogens in ground beef.
• To assess the impact of inoculation timing on the probiotic's inhibitory effect.

Main Methods:

• Ground beef samples were inoculated with specific pathogens (E. coli O157:H7, S. aureus, C. perfringens, L. monocytogenes) and Enterococcus faecalis CECT7121.
• Three experimental designs were used: simultaneous inoculation, probiotic pre-inoculation (24h), and pathogen pre-inoculation (24h).
• Viable bacterial counts were determined at 0, 24, 48, and 72 hours post-inoculation.

Main Results:

• Simultaneous inoculation of E. faecalis CECT7121 with E. coli O157:H7 led to no viable bacteria at 72 hours.
• Probiotic application before or after pathogen inoculation significantly reduced E. coli O157:H7 counts within 24-48 hours.
• E. faecalis CECT7121 demonstrated consistent bactericidal activity against S. aureus, C. perfringens, and L. monocytogenes across all tested conditions.

Conclusions:

• Enterococcus faecalis CECT7121 exhibits significant bactericidal activity against major foodborne pathogens in ground beef.
• The timing of probiotic application influences the speed of pathogen reduction.
• This probiotic holds promise as a natural agent to improve the microbiological safety of ground beef products.