Influence of Alaria esculenta powder on sensory acceptance, nutritional aspects, and staling of wheat bread

• Inclusion of 5 % of Alaria esculenta maintains bread sensory acceptability. • Fortification increases protein (1.26-fold), fiber (1.47-fold), and ash (5.63-fold). • B-5A exhibits slower starch retrogradation and improved protein structural order. • Protein hydrophobicity decreases gradually in Alaria-bread improving water retention. • 5 % A. esculenta in bread delays staling, extends shelf life, have no cytotoxicity. This study investigated the nutritional, sensory, physiological, and shelf-life impacts of incorporating Alaria esculenta seaweed powder into wheat bread. Structural analysis showed that high levels (7.5–10 %) reduced porosity and volume, whereas moderate inclusion (2.5–5 %) maintained favorable crumb properties. Sensory evaluation revealed overall acceptability scores of 8.15 for control bread (B-C) and 8.12 for bread with 5 % A. esculenta (B-5A). Proximate composition analysis showed increases in protein (1.26-fold), fiber (1.47-fold), and ash (5.63-fold) in B-5A, while energy value and carbohydrate contents decreased (1.48- and 1.26-fold, respectively). In vitro assays using THP-1 macrophages and Caco-2 cells confirmed the absence of cytotoxicity up to 200 µg/mL, with slight viability enhancements. Inflammatory gene expression (IL6, IL8, MCP1, TNFα) remained unchanged, with a modest IL6 reduction in Alaria -treated macrophages. In vivo glycemic testing showed moderated postprandial peaks for B-5A and B-C (≈130 mg/dL at 30 min) compared with glucose (146 mg/dL at 15 min), while B-5A maintained a more stable plateau between 90–120 min, suggesting prolonged satiety. During storage, B-5A exhibited superior moisture retention (28.12 % vs. 22.01 %), slower starch retrogradation (44.76 %→47.95 % vs. 45.27 %→50.29 %), and a more ordered protein structure, with greater increases in α-helix (+14.13 %) and reductions in random coil (–12.40 %). Protein surface hydrophobicity evolved more gradually in B-5A (contact angle decrease 40.48°→35.51°) than in B-C (66.86°→50.92°), reflecting enhanced water-binding. Collectively, these differences indicate slower staling and extended shelf life. Overall, 5 % A. esculenta fortification enhances nutritional quality, delays staling, improves shelf life, and maintains consumer acceptability without adverse cytotoxic or inflammatory effects.