Enrichment of Wheat–Chia Bread with Hemp, and Buckwheat Flours and Cistus incanus L. Infusion: Impact on Chemical Composition, Polyphenols, Fatty Acids, Amino Acids, and Consumer Acceptance

This study aimed to assess whether hemp or buckwheat flour, and the replacement of water with cistus infusion, can simultaneously improve the nutritional value and antioxidant potential of wheat–chia bread while maintaining acceptable sensory quality. Control bread (WCh) and variants with hemp flour (WChH) or buckwheat flour (WChB), prepared with either water or cistus infusion (Cis), were baked. The chemical composition, amino acid profile and protein quality (AAS), fatty acid profile, phenolic compounds and antioxidant properties (TPC, FRAP), color (CIELAB), and texture were determined. E-tongue and e-nose analyses, as well as consumer evaluation, were also performed. Hemp flour most significantly increased the protein and dietary fiber content of bread and improved the PUFA content and PUFA/SFA ratio. Buckwheat flour shifted the lipid profile toward MUFA and yielded the highest lysine AAS, although lysine remained the limiting amino acid in all variants. Cistus infusion increased the polyphenol pool and antioxidant activity, with the strongest effect observed in the combined WChH/Cis and WChB/Cis systems. Electronic nose and an electronic tongue analyses confirmed significant differentiation of the flavor and aroma profiles among variants. Consumer evaluation showed a decrease in acceptance following hemp flour addition, which was partially mitigated by cistus infusion, while buckwheat variants maintained good sensory acceptance.