Synergistic Impact of Pomegranate Peel Extract and High Hydrostatic Pressure on Controlling Discolouration and Oxidation in Iberian Dry Sausage Throughout Storage

This study aimed to assess the impact of high-pressure processing and the inclusion of a pomegranate peel extract (PPE) on colour, antioxidant residual activities and lipid and protein oxidation of dry-cured and uncured sausages during 120 days of refrigerated storage. Nitrite and PPE were added into the sausage formulations following four treatments: (1) 150 mg/kg NaNO₂ (C_Pos), (2) 0 mg/kg NaNO₂ (C_Neg), (3) 0 mg/kg NaNO₂ + 1% PPE (PPE1) and (4) 0 mg/kg NaNO₂ + 2% PPE (PPE2). The four dry sausage batches were divided into two groups, one left untreated (0.1 MPa) and the other subjected to high hydrostatic pressure treatment (600 MPa, 8 min). The results revealed significant differences in the initial oxidation levels, with nitrite removal leading to increased lipid peroxidation and protein carbonylation. The pomegranate extract surpasses nitrite in the amount of residual antioxidant activity in the sausages and was comparable to nitrites in controlling lipid and protein oxidation. Despite this, thiols were affected, decreasing their value in batches with added pomegranate extract. Finally, the colour of the dry sausages varied significantly towards more yellowish and less reddish when the pomegranate extract was added.