bioprotection; beef; vacuum packaging; Carnobacterium; shelf life
Abstract :
[en] Temperatures near the freezing point of meat (−1.5 °C), associated with vacuum packaging,
allows the preservation of this product up to several months, which makes possible the meat
trade across the planet without resorting to freezing. Other the type of packaging and the
storage temperature, the shelf-life of meat is directly related to its initial microbiological
ecosystem and its evolution. Carnobacterium maltaromaticum is a lactic acid bacterium, and
many lactic acid bacteria associated with meat are known for their bactericidal or
bacteriostatic activity against other strains, species or genera of bacteria. In this way, the
presence of certain lactic acid bacteria adapted to a low temperature in fresh meat could
extend the shelf life and improve the microbial stability and safety of this product. The aim of
this study was to perform a morphological and functional characterization of a
C. maltaromaticum strain (lab. ref. CFAUS2/DLC/4/E1) with potential bioprotective effect
isolated from commercial vacuum packaged long shelf life beef. The morphological,
biochemical and enzymatic profiles, the influence of different temperatures and atmospheres,
and the microbial stability of fresh beef inoculated with the C. maltaromaticum strain were
evaluated. Morphological, biochemical and enzymatic profiles of the isolated
C. maltaromaticum strain were similar to those of two reference strains (LMG 11393 and
LMG 22902). The evaluation of the influence of different atmospheres showed that the
growth of C. maltaromaticum was the slowest in an atmosphere containing 70 % O2 and
30 % CO2. Vacuum packaging is therefore more suitable for the growth of this bacterium. An
antimicrobial effect against Enterobacteriaceae was highlighted on inoculated fresh meat.
The functional characterization of this strain will be further pursued by genotypic
characterization and its potential bioprotective effect will also be studied.
