Hazelnut skin polyphenolic green extract as a promising natural antioxidant in pork burgers: Assessment of quality parameters and consumer acceptance.

Given the increasing consumer focus on healthier and environmentally friendly foods, the use of natural antioxidants in food production is becoming more common. The recovery of these antioxidants from agri-food waste is crucial for a circular economy, as it revalues matrices that would otherwise become waste. This study aimed to assess the antioxidant capacity of hazelnut skin and its green polyphenolic extract and to evaluate their effect on some qualitative parameters of pork burgers. Three types of burgers were formulated: a control group, and two experimental groups with the addition of 2.5 % of hazelnut skin or 1 % of hazelnut green extract. On days 0 and 7 of refrigerated storage (0-2 °C) parameters such as color, cooking losses, tenderness, lipid oxidation, and volatile profile were evaluated. Additionally, a group of panelists was asked to assess the acceptability of color and the potential for purchase. In both raw and cooked burgers, at all times examined, the two experimental groups showed a significant improvement in oxidative stability and lower production of volatile fat oxidation compounds compared to the control in which the main indicators of pork meat spoilage were detected. Although, even if on the 7th day of storage, the HS and HSE burgers exhibited better color stability, these groups showed a worsening in terms of color acceptability and tenderness. Overall, despite trade-offs, the hazelnut skin and their green extract showed high potential to emerge as food additives in meat products.