Bioaccessibility of black cumin (Nigella Sativa L.) tea polyphenols: influence of pine honey and flower honey addition and infusion temperature

This study investigates the impact of pine honey and flower honey addition, as well as infusion temperature, on the bioaccessibility of polyphenols and antioxidant capacity in black cumin (Nigella sativa L.) tea. The tea formulations were subjected to simulated gastrointestinal digestion, after which the phenolic profile was analyzed using HPLC–PDA. Protocatechuic acid, catechin, p-hydroxybenzoic acid, and syringic acid were identified as the major phenolic compounds. Infusion at 80 °C significantly increased the total phenolic content in the digested phase compared to lower temperatures (p < 0.05). Antioxidant capacity analysis revealed substantial losses in activity post-digestion, with reductions of 82–92% in the CUPRAC assay and 26–62% in the DPPH assay. HPLC–PDA analysis confirmed that salivary and gastric digestion negatively impacted individual phenolic compound levels in all samples. Notably, pine honey addition enhanced total phenolic content, while both honey types exhibited a synergistic effect with black cumin, leading to higher measured values than expected. These findings provide insights into optimizing black cumin tea formulations for improved bioaccessibility of polyphenols.