Squid by-product gelatines: Effect on oxidative stress biomarkers in healthy rats

Gelatines from three different jumbo squid (Dosidicus gigas) by-products (fins, arms, and skin) were compared based on their chemical and biochemical properties (amino acid composition, molecular weight distribution, and in vitro digestibility), antioxidant capacity (ABTS⁺ and ORAC assays) and effect on oxidative stress biomarkers (serum antioxidant capacity (TAC) and serum malondialdehyde levels (MDA)) in healthy rats. Gelatine from the skin showed the highest polar and imino amino acid contents and a higher proline hydroxylation degree. Gelatine β-component was not detected in either fins or arms. These differences may explain the higher in vitro digestibility and higher antioxidant capacity (before and after digestibility) of the skin gelatine. Fin gelatines decreased TAC-ORAC values. All obtained gelatines decreased the MDA levels. Jumbo squid gelatine, administered during feeding, may help decrease a breakdown product of spontaneous lipid peroxidation in serum.