Physicochemical properties and sensory features of ripened, industrially prepared sausages, enriched with olive leaf extract to replace nitrite and nitrate

The use of nitrite and nitrate in meat products has been questioned due to the generation of N-nitroso compounds with carcinogenic effects. Thus, research has been focused on their replacement with several alternatives. This study is focused on evaluating the effects of a commercial olive leaf extract (OLE), marketed as dietary supplement, on protein and lipid oxidation, N-nitrosamine content and sensory properties of industrial sausages at the end of the ripening period. Five different formulations were prepared: F1 (OLE: 1000 mg/kg; NO2–NO3: 0 mg/kg), F2 (OLE: 1000 mg/kg; NO2–NO3: 75-75 mg/kg), F3 (OLE: 0 mg/kg; NO2–NO3: 0 mg/kg), F4 (OLE: 0 mg/kg; NO2–NO3: 75-75 mg/kg), F5 (OLE: 500 mg/kg; NO2–NO3: 35-35 mg/kg). The use of OLE in combination with a reduced dose of nitrite and nitrate (F5) significantly reduced the lipid and protein oxidation (p < 0.05) compared to the formulation with synthetic additives alone (F4). No differences were observed in terms of textural properties with the samples without the extract. The OLE did not affect the microbiological quality and enabled a significant reduction in the N-nitrosamines content. However, the addition of OLE decreased the intensity of red colour and determined the insurgence of a slight bitter taste in the sausages.