Evaluating the antioxidant activity of aqueous extract of date pits in improving the chemical stability of freeze-storied beef

Resumo

Meat derived from older cows represents an economically important protein source; however, its reduced consumer acceptance is largely attributed to increased connective tissue cross-linking and heightened susceptibility to oxidative deterioration during storage. This study investigated the efficacy of aqueous date seed extract (from Phoenix dactylifera L.) as a natural antioxidant in improving the oxidative stability of aged beef stored at −18°C for 90 days. Four treatments were evaluated (0, 5, 10, and 15% extract; CRD design), and lipid and protein oxidation markers were quantified. Frozen storage significantly increased oxidative indices in all samples (P ≤ 0.05). After 90 days, control samples exhibited the highest lipid oxidation, with FFA reaching 0.75% and TBA values 5.55 mg MDA/kg. In contrast, the 10% extract treatment reduced FFA to 0.50% (≈33% reduction), while the 15% treatment lowered TBA to 5.03 mg MDA/kg. Peroxide values decreased from 8.75 mEq/kg fat (control) to 7.62 mEq/kg in the 10% treatment. Protein oxidation followed a similar pattern; carbonyl content declined from 2.12 to 1.92 nmol/mg protein, whereas thiol concentration was preserved at 59.80 µmol/g protein in the 15% treatment compared to 52.42 µmol/g in controls. The observed protective effect is attributed to phenolic-mediated radical scavenging and potential metal-chelating activity of date seed bioactives, limiting both primary and secondary oxidation products. Collectively, supplementation with 10–15% aqueous date seed extract demonstrates significant potential as a clean-label antioxidant strategy to enhance oxidative stability and extend the storage life of frozen aged beef.