Nutritionally Improved Gluten-Free Breads Fortified with Soluble Fiber and Bioactives Compounds from Artichoke and Broccoli By-Products

BACKGROUND: Commercial gluten-free (GF) breads often exhibit low nutritional quality due to limited fiber and bioactive compounds. The enzymatic treatment of vegetable by-products, such as broccoli and artichoke, represents a sustainable strategy to release soluble dietary fiber and phenolic compounds, enhancing the functional value of GF products. Five GF bread formulations were developed: a control bread, breads containing broccoli or artichoke extracts (BB and BA), and breads with enzymatically treated extracts using Viscozyme® L and Celluclast® 1.5L (BBE and BAE). A commercial GF bread (BC) served as a reference. Nutritional composition, dietary fiber fractions, phenolic content, antioxidant capacity, starch digestibility, physicochemical parameters, and sensory properties were evaluated. RESULTS: Enzymatic treatments significantly improved the nutritional and functional properties of GF breads. Viscozyme L® produced the highest increases in antioxidant capacity and phenolic content (up to 30% higher in FRAP), while Celluclast® 1.5L generated the highest rise in soluble dietary fiber (up to 2.75 g/100g) and the best sensory acceptance. Moreover, Celluclast® 1.5L significantly modified starch digestibility, reducing rapidly digestible starch by 14% and increasing slowly digestible starch by over 150%, suggesting a lower predicted glycemic response. CONCLUSIONS: Incorporating the enzyme-treated artichoke and broccoli by-products into GF breads effectively enhances soluble fiber, antioxidant potential, and sensory quality. Among treatments, Celluclast® 1.5L applied to artichoke proved most effective overall, providing a balanced improvement in nutritional and functional attributes. These findings revealed the potential of Celluclast® 1.5L-treated artichoke by-products as a source of natural bioactive compounds for developing clean-label, nutritionally enhanced GF breads.