Potential of date palm spikelet extract as an anti-oxidative agent in set-type yogurt during cold storage

Abstract

The study aimed to evaluate the effects of date palm spikelet extract (DPSE) from two cultivars on the chemical, antioxidants, and sensory properties of yogurt. The DPSE of Rziz (Rz) and Khalas (Kl) cultivars contains high levels of total phenolics and flavonoids as well as phenolic compounds with an antioxidant activity exceeded 90%. Increasing the DPSE concentration in yogurt improved the levels of total solids, protein, ash, total phenolic compounds, flavonoids, and antioxidant activity even during prolonged storage periods. The thiobarbituric acid reactive substances (TBARS) of yogurt was decreased by adding DPSE but increased with storage time. Throughout the storage period, the DPSE-formulated yogurt revealed better stability in terms of its physicochemical, antioxidative, and sensory characteristics compared to non-formulated yogurt. The findings of this study proved the antioxidant potential of 0.5–1% DPSE for both cultivars, with the superiority of the Rz extract as a functional additive to preserve yogurt.