Evaluation of a Three-Component Plant Derived Extract as Preservative for Fresh Retail Meat
The aim of this study was to evaluate the potential of a threecomponent plant derived extract as a preservative of fresh retail meat. The metabolomic fingerprint of the extract was obtained by High Performance Thin Layer Chromatography. The antibacterial activity of the extract against the spoilage bacteria: Carnobacterium maltaromaticum, Brochothrix thermosphacta, Escherichia coli, Pseudomonas fluorescens, Lactobacillus curvatus and L. sakei was assessed in a broth model meat system. The bacterial growth inhibition zone (mm) ranged from 27.33 ± 0.68 to 30.00 ± 1.00, as was found by disc diffusion test with 100 μL extract, 100 μL ciprofloxacin (wt/v) as positive control and 100 μL sterile distilled water as negative control. The bacterial percent growth reduction ranged from 86.31 ± 1.15 to 90.51 ± 1.15; from 78.79 ± 1.00 to 91.53 ± 2.08; from 61.18 ±1.30 to 69.21 ± 0.50; from 36.56 ± 1.10 to 62.83 ± 1.33 in the broth microdilution method at different extract dilutions (1:10 to 1:100,000). Viable bacterial cells were detected in experimentally-contaminated minced meat up to the second day after treatment (100 μL extract per 10 g meat), except for C. maltaromaticum and P. fluorescens, which were detected up to the 4th day, by PCR and nested PCR with propidium monoazide (PMA™) dye. On the basis of the reported results the tri-component plant derived extract should be considered as a potential preservative for fresh retail meat.
Paola Del Serrone, Chiara Toniolo and Marcello Nicoletti