Enzymatic Deastringent Fruit Powder of Sea Buckthorn (Hippophae rhamnoides L.): Preparation, Antioxidant Activity Investigation and Metabolomics Analysis

Sea buckthorn is a valuable medicinal and edible plant, but the sour and astringent taste of its fruit limits the development of the related processing industry. This study focused on establishing the optimal composite enzymatic hydrolysis strategy to reduce acerbity during processing of sea buckthorn berries, while preserving the antioxidant activity. The results indicated that the most effective conditions for deacidification and deastringency were achieved with a pectinase-to-tannase mass ratio of 1:1, an enzyme dosage of 0.20%, at a pH of 4.50, a temperature of 50 °C, and a duration of 4 h. Under this treatment, the sea buckthorn could retain its potent antioxidant activity. Furthermore, a significant alteration was observed in the levels of 36 metabolites, which were correlated with the sensory attributes of the sea buckthorn. The findings of this study provided a theoretical basis for the enhanced utilization of sea buckthorn in processing and for a deeper understanding of its bioactive properties.