Evaluation of the in vitro antimicrobial activity of mixtures of Lactobacillus sakei and Lactobacillus curvatus isolated from argentine meat and their effect on vacuum-packaged beef

A L. sakei and a L. curvatus-based mixtures exerted an antagonistic activity in vitro against 12 different spoilage and pathogenic bacteria. No activity was exerted by the cell-free supernatants. The addition of the two mixtures to sliced vacuum-packaged beef showed a better capability of L. sakei to adapt to meat substrate. After 60 days, Total Viable Count (5.8 vs 7.4 Log CFU/g), Gram-negative bacteria (2.5 vs 6.4 Log CFU/g) and Enterobacteriaceae (2.3 vs 4.4 Log CFU/g) were significantly lower in L. sakei-inoculated samples if compared with control ones; TVC and Enterobacteriaceae were also significantly lower in L. curvatus-inoculated samples than control ones. The addition of mixtures gave no significant effects on meat pH and colour. The use of high dosage of viable cells could be suggestible in order to exert an early conditioning of meat environment.