Stability of Polyphenols and Antioxidant Activity of Cellulose-Based Encapsulates Enriched with Tart Cherry Juice Polyphenols

This study investigated the potential of cellulose as a carrier for bioactive phenolic compounds from tart cherry juice. Using a freeze-drying method, encapsulates were prepared by varying cellulose content (2.5%, 5%, 7.5%, and 10%) and complexation times (15 and 60 min) while maintaining a constant juice volume. The prepared encapsulates were characterized by determining the concentrations of total phenols, monomeric anthocyanins, and proanthocyanidins, alongside antioxidant activity by spectrophotometric methods, individual polyphenols by HPLC, color parameters and structural changes via IR spectroscopy. Additionally, the stability of these parameters was evaluated after one year of storage at room temperature. Results indicated that the highest concentrations of phenolic compounds and the strongest antioxidant potential were achieved with 2.5% cellulose content (the lowest content) after 15 min of complexation (shorter time). Concentrations of polyphenols decreased as the cellulose contents increased. Although changes in chemical parameters occurred during storage, the results confirm that cellulose is a viable carrier for tart cherry phenolics, particularly at lower contents, offering a promising approach for formulating stable bioactive delivery systems.