Malva sylvestris L.-Enriched Wheat Crackers: Nutraceutical Properties, Bioaccessibility, and Starch Digestibility

This preliminary study evaluated the feasibility of incorporating Malva sylvestris L. (mallow) leaf flour as a functional ingredient in baked products. Crackers enriched with 5% mallow flour were developed and compared with traditional wheat-based crackers. Antioxidant capacity, total polyphenol and flavonoid contents, starch digestibility, and the potential bioaccessibility of nutraceutical compounds were assessed using colorimetric assays and an in vitro digestion model. Despite the low inclusion level, enriched crackers exhibited significantly greater antioxidant capacity than control crackers (1.27 vs. 0.77 mmol Fe²⁺E/100 g). After simulated digestion, the liquid fraction of mallow-enriched crackers showed higher antioxidant capacity (6.04 vs. 3.92 mmol Fe²⁺E/100 g), suggesting a higher amount of potentially bioaccessible antioxidant compounds. Total polyphenol content was also higher in the enriched formulation (75.09 vs. 54.03 mg GAE/100 g), as were polyphenols and flavonoids in the digested liquid fraction. In contrast, no significant differences were observed in total digestible starch or in the proportions of rapidly digestible, slowly digestible, and resistant starch fractions. These results suggest that mallow leaf flour may enhance the antioxidant and phytochemical profile of crackers without significantly altering starch digestibility, supporting its potential use as a functional ingredient in innovative snack products.