Control of Listeria monocytogenes in model sausages by enterocin AS-48.
In this work we describe the control of Listeria monocytogenes CECT 4032 in sausage by adding the enterocin AS-48 producer strains Enterococcus faecalis A-48-32 and Enterococcus faecium S-32-81, and also by adding a semi-purified preparation of the bacteriocin. Addition of preformed AS-48 caused a significant decrease (P<0.01) in the number of viable listeria even at the lowest bacteriocin concentration tested (112 AU/g). At a higher concentration (225 AU/g) listeria were below the detection level (1.99 log units/g) in meat at 3 days of incubation but growth of listeria was observed again after 9 days. For an AS-48 concentration of 450 AU/g, no viable listeria were detected after 6 and 9 days of incubation. When E. faecalis A-48-32 was used as inoculum at approximately 10(7) cfu/g, listeria counts decreased progressively from start of experiment, being below detection level at day 9. The best results were obtained with E. faecium S-32-81, since listeria were undetectable at 6 days of incubation. Bacteriocin concentrations in samples reached concentrations of 60 and 80 AU/g for strains A-48-32 and S-32-81, respectively. These results clearly indicate that AS-48 can be used in the control of L. monocytogenes in sausages.
Ananou
Samir
S
Departamento de Microbiología, Facultad de Ciencias, Universidad de Granada, Fuentenueva s/n, 18071-Granada, Spain.
Garriga
Margarita
M
Hugas
Marta
M
Maqueda
Mercedes
M
Martínez-Bueno
Manuel
M
Gálvez
Antonio
A
Valdivia
Eva
E
D000818:Animals; D001430:Bacteriocins / Q000494:pharmacology*; D015169:Colony Count, Microbial; D004305:Dose-Response Relationship, Drug; D005285:Fermentation; D005516:Food Microbiology; D005519:Food Preservation / Q000379:methods*; D008089:Listeria monocytogenes / Q000254:growth & development*; D008461:Meat Products / Q000382:microbiology*; D013552:Swine; D013997:Time Factors
D001430:Bacteriocins; C466236:enterocin AS-48, Enterococcus faecalis