Biomedical Engineering Reference
In-Depth Information
It was proposed that
L. curvatus
CRL705 protective cultures could contribute to meat
ageing by generating small peptides and free amino acids, while improving shelf life
(Fadda et al.
2008
).
Inoculation with a sakacin A producer
L. sakei
strain reduced the population
of
L. monocytogenes
on vacuum-packed lamb during 12 week storage. Similarly,
inoculation with BLIS-producing
L. sakei
strains delayed blownpack spoilage caused
by
Clostridium estertheticum
and reduced the survival of
Campylobacter jejuni
on
beef meat (Jones et al.
2009
). In vacuum-packaged chicken cuts, inoculation with
sakacin-P producing
L. sakei
achieved a growth inhibition of
L. monocytogenes
(Katla et al.
2002
). Plantaricin-producing
L. plantarum
showed anti-listerial effects
in uncooked and cooked chicken meat (Enan
2006
; Gamal
2006
). Enterococci have
also been tested as protective cultures in raw meats. In chicken ground meat stored
at 8-10 °C, growth of
L. monocytogenes
and
S
. Enteritidis was adversely affected by
the respective presence of protective cultures consisting of strain
E. faecium
PCD71
(carrying the genetic determinants for enterocins A, P, L50A and L50B) and strain
L. fermentum
ACA-DC179, producer of BLIS against
Salmonella
(Maragkoudakis
et al.
2009
; Zoumpopoulou et al.
2008
). Strain
E. faecium
PCD71 inhibited the
growth of
L. monocytogenes
by at least 0. 7 log CFU/g after 7 days storage, while
strain
L. fermentum
ACA-DC179 inhibited the growth of
S
. Enteritidis by up to 1.3
log CFU/g compared to the control (Maragkoudakis et al.
2009
). In addition, none
of these two strains caused detrimental effects on biochemical parameters related to
spoilage of the chicken meat.
4.2.2
Semi-processed and Cooked Meats
Lactic acid bacteria are the prevalent spoilage microorganisms in cooked meat prod-
ucts (Mataragas et al.
2006
, Audenaert et al.
2010
, Chenoll et al.
2007
). The shelf life
of most heat processed meats is limited by
Lactobacillus
and
Leuconostoc
strains
that rapidly recontaminate the product during handling and slicing (Lücke
2000
).
These LAB also tend to displace pathogenic bacteria. In the absence of competing
microbiota,
L. monocytogenes
will proliferate more easily. Specifi c bacteriocin-
producing LAB strains could be used as protective cultures for semi-processed and
cooked meats provided that they cause only a minimal change in the desired sensory
properties of the products while inhibiting
Listeria
and displacing other LAB
involved in spoilage (Hugas et al.
1998
; Lücke
2000
; Chen and Hoover
2003
;
Aymerich et al.
2008
; Galvez et al.
2008
). Bacteriocin-producing protective cultures
have been shown to inhibit
L. monocytogenes
in vacuum-packaged processed meats,
such as
Lactobacillus bavaricus
MN in minimally heat-treated beef cubes
(Winkowski et al.
1993
),
P. acidilactici
JBL 1095 in wieners (Degnan et al.
1992
),
or
P. acidilactici
JD1-23 in frankfurters (Berry et al.
1991
). In Brazillian raw sausage
lingüiça, bacteriocin-producing
Lactobacillus sake
2a also inhibited growth of
L.
monocytogenes
(Liserre et al.
2002
). The bacteriocinogenic strains
L. sakei
CTC494
