Abstract
Avocado processing generates seed by-products rich in dietary fiber that can be upcycled into functional ingredients. This study modified and characterized avocado seed flour via extrusion and enzyme-assisted wet-milling, as well as evaluated its use in wheat bread. The flour was fractionated, and fraction 2 (F2) was selected based on techno-functional performance; it was tested in its non-extruded (NEF2) and extruded (EF2) forms. Breads were prepared by replacing 5% of wheat flour with NEF2 and EF2 (NEB and EB, respectively). Compared with NEF2, EF2 had an 81% higher water absorption index (WAI) and an 18% higher oil absorption index (OAI). Extrusion reduced antioxidant activity ~1.6-fold, consistent with an ~85% decrease in acetogenin content, indicating thermo-mechanical degradation of bioactives linked to bitterness. Analyses were conducted in triplicate (p < 0.05). By day 3, crumb hardness increased (EB: 9.65 N; NEB: 6.04 N; control: 5.49 N). In a test with 106 consumers, aroma scores improved for NEB (8.00, IQR 7.00-8.00) and EB (7.00, IQR 5.00-8.00) versus the control (6.00, IQR 4.00-7.00), while overall acceptability, texture, color, and appearance did not differ. These results support EF2 as a functional upcycled ingredient that enhances hydration and aroma, reduces bitterness, and maintains consumer acceptance, aligning with circular economy and clean-label goals.