Selection of a Natural Extract Rich in Antioxidants to Reduce Lipid and Protein Oxidation in Rabbit Meatballs During Refrigerated Storage

Although consumption of rabbit meat is limited worldwide, it is highly nutritious and offers significant health benefits. Lipid and protein oxidation affect the quality and acceptability of rabbit meat products by consumers. These processes can be suppressed using nonharmful antioxidant agents, such as polyphenol‐rich extracts obtained from natural sources. This paper compared the antioxidant properties of extracts obtained from Euphorbia antisyphilitica (Ea), Momordica charantia , Acrocomia aculeata , and Dactylopius opuntiae to select the best antioxidant extract. This extract was used in ready‐made rabbit meatballs to evaluate its preservative actions during refrigerated storage. Among all extracts, the Ea extract exhibited the highest polyphenol content and antioxidant activity compared with the other extracts (Ea semisolid extract contained 337.45 ± 11.53 mg GAE/g and showed half‐maximal inhibitory concentrations IC 50 ′s of 66.32 ± 11.47 and 755.60 ± 132.4 μ g/mL against DPPH and ABTS radicals, respectively). As the selected semisolid extract could not be added to meat, a drying step was applied to obtain a powdered extract, which exhibited higher polyphenol amount (485.97 ± 29.05 mg GAE/g) and antioxidant activity (IC 50 ′s of 47.36 ± 2.55 and 549.6 ± 36.81 μ g/mL against DPPH and ABTS radicals, respectively) than its semisolid form. To obtain the powdered form, a simple method was employed (samples were heated at 200°C for 2 min and pulverized using a mortar and pestle). Compared with preservative‐free meatballs, meatballs fortified with the powdered Ea extract showed reduced cooking loss (reduction of 33.8% from the comparative value), enhanced color and antioxidant ability (antioxidant increase of up to 101.7% from the comparative value), and suppressed lipid and protein oxidation (reduction of up to 71.4% and increase of 81.3% from comparative values for lipid deterioration and protein preservation, respectively). Therefore, this natural powder has the potential to be used as a preservative in the meat industry after additional tests, such as sensory evaluations, among others.