The use of sodium chloride in meat products such as beef jerky, in addition to its sensory and
preservative effect, gives them stability, prolonging the shelf life of the product. Despite being
a preservative, non-sterile salt may contain microorganisms adapted to high saline
concentrations, called halophiles, which can cause deterioration problems, such as unpleasant
odors and aromas in the products. The objective was to isolate, characterize, evaluate growth
parameters and production of hydrolytic exoenzymes, as well as assess the sensitivity to organic
acid preservatives (lactic, citric and glucone-delta-lactone) in strains isolated from jerked beef
in a state of deterioration. Two strains were isolated, the C11 strain of cream white and coccoid
colony, and the V22 red-pigmented and morphologically pleophoric. Both were neutrophils,
gram-negative, catalase and oxidative positive and after a 2x3 factorial experimental design,
evaluating the influence of different concentrations of NaCl, MgCl2 and yeast extract, it was
observed that for both the best growth conditions of the variables studied were of 25 to 35 g L-
1 of MgCl2, 5 g L-1 of yeast extract, but in relation to NaCl the C11 strain did not grow in a
medium containing 300 (ideally 200) g L-1 and the V22 strain did not grow in medium
containing 100 (ideally 300) g L-1. As for the enzyme production tested in specific solid media
with different substrates, the results show that the two strains were negative when producing
exoenzymes, except for the V22 strain that showed a good IE (4.5) for gelatinase production.
In the evaluation of the susceptibility of the deteriorating strains to the due acids, the technique
of diffuse disk in agar was used (Kirby-Bauer method) with different acids varying their
concentrations from 0.5 to 5% diluted in brine to 20% of NaCl and the Results show that, in
general, the use of a concentration from 2,5% can be used to increase the shelf life of the jerky,
but that lactic and citric acids presented higher significant values in relation to the inhibition of
the growth of the strains tested in vitro at different concentrations.
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