Effect of beetroot (Beta vulgaris) extract on Black Angus burgers shelf life

Beef burgers are meat preparations with easy perishability. To ensure a longer shelflife, the Regulation EU 1129/11 allows the use of some additives. However, healthconscious consumers prefer products which do not contain synthetic substances. Aim of the present study was to evaluate the effect of Red Beetroot (Beta vulgaris) integration on Black Angus made burgers shelf life. Red beet was prepared as powder and added to meat mixture as the same or in water solution. The study was split into 2 trials to assess the extract activity also in burgers vacuum-packaged stored. Burgers were analysed (up to 9 days at 4°C) in terms of sensory properties, microbiological profile, pH, a(w) and lipid oxidation (TBARS). At the end of storage, treated samples showed the highest values of redness and the lowest content of malondialdehyde, probably due to antioxidant properties of red beet towards myoglobin and lipid oxidation processes. Moreover, results highlighted that Red Beetroot activities were dose-dependent and intensified if dissolved in water. The a(w) values did not appear to be conditioned by extract integrations, unlike the pH that was lower in treated samples than control ones. Microbiological analyses identified beetroot as a potential antimicrobial substance, especially in high concentration. In conclusion, Beta vulgaris extract could be proposed as natural compound exploitable in beef burgers to preserve qualities and extend their shelf-life.