Biomedical Engineering Reference
In-Depth Information
Chapter 4
Biopreservation of Meats and Meat Products
4.1
Application of Bacteriocin Preparations
4.1.1
Raw Meats
The microbial populations most frequently associated with the meat environment
are known to primarily belong to the groups Enterobacteriaceae, lactic acid bacteria
(LAB),
Brochothrix thermosphacta
, and pseudomonads (Borch et al.
1996
; Labadie
1999
; Nychas et al.
2008
). Microbial metabolism of meat during growth results in
microbial spoilage, with the development of offodors which make the product unde-
sirable for human consumption (Jackson et al.
1997
). Also, pathogenic bacteria
initially present at low concentrations may grow during meat spoilage may prolifer-
ate during refrigeration storage, especially
Listeria monocytogenes
.
In raw meats, bacteriocins have been tested alone or in combination with other
hurdles for carcass decontamination and/or to inhibit bacterial growth on stored
fresh meats (Table
4.1
). Washing, spraying or dipping with bacteriocin solutions
have been tested alone or in combination with other antimicrobials to potentiate
bacteriocin activity. In order to increase the effi cacy of treatments and/or avoid cross
contamination, raw meats are chilled, packaged under different atmospheric condi-
tions such as vacuum packaging, MAP, or active packaging with O
2
scavengers or
CO
2
generating systems (Coma
2008
; McMillin
2008
). Additional combinations
such as low dose irradiation, UV surface decontamination or HHP have been pro-
posed (Aymerich et al.
2008
). All these processing treatments have selective effects
the initial microbiota, and may act in synergy with bacteriocins to increase the prod-
uct safety and shelf life. Although raw meat products are further processed prior to
consumption by treatments that usually destroy pathogenic bacteria, they can be a
considerable source of cross contamination. Growth of toxin-producing bacteria in
raw materials (such as minced meats) should also be controlled, especially for heat-
stable toxins.
