Effects of olive mill vegetation water phenol metabolites transferred to muscle through animal diet on rabbit meat microbial quality

The present study evaluated the effects of feed supplementation with olive oil by-products on the microbial quality of rabbit meat. Thirty-three New Zealand White rabbits were randomly assigned to three experimental grower–finisher diets. Each dietary group consisted of three experimental treatments: (1) a basal control diet (C), (2) a C diet supplemented with a low dosage of polyphenol (150 mg/kg, L), and (3) a C diet supplemented with a high dose of polyphenols (280 mg/kg, H). Polyphenol analyses in feed and meat were performed using the liquid-chromatography coupled to tandem mass spectrometry technique (LC-MS/MS). Higher amounts of sulphate metabolites were detected in the H group. Microbiological quality was evaluated on Longissimus lumborum muscles stored under aerobic conditions at 4◦ C. The H diet exerted an inhibitory effect on microbial growth (p < 0.001), notably for Pseudomonas spp., when compared to C and L diets; differences among the groups were observed starting from 6 days of storage. In the H group, the Pseudomonas spp. population showed an increase in the latency phase and a decrease in the maximum growth rate of the fitted curves in comparison with the C and L groups. The use of dietary polyphenols could be a strategy to reduce spoilage during meat storage.