Physical, phytochemical and sensory characteristics of extruded high-fiber breakfast cereals prepared by combining carrot by-products with wheat and oat bran

High-fiber breakfast cereals are mainly produced by extrusion, and to improve its nutritional/nutraceutical properties, the addition of raw materials rich in bioactive compounds has been suggested. The aim of this study was to evaluate the physical, phytochemical and sensory characteristics of extruded high-fiber breakfast cereals (HFB) prepared from carrot by-products and bran as affected by feed moisture (FM, 19.34–30.66%) and carrot pomace content (CPC, 5.51–22.49%), under a central composite rotatable experimental design. When FM was increased, flexural modulus (FMO, 54-89 MPa), soluble dietary fiber (SDF, 0.64-4.18%), bound phenolic compounds (BPC, 0.02-0.25 mg GAE/g), and DPPH antioxidant activity from BPC extracts (2.07-2.29 µmol TE/g) increased, whereas expansion index (1.09-0.89) diminished. Also, when CPC was elevated, FMO (54-83 MPa), water solubility index (14.21-18.84%), color b* (26.8-28.8), insoluble dietary fiber (19.43-24.71%), SDF (1.12-3.98%), free phenolic (0.56-0.71 mg GAE/g), and flavonoids compounds (0.05-0.31 mg QE/g) increased, whereas BPC decreased (0.25-0.14 mg GAE/g). The HFB presented good (≥ 69%) sensory acceptability. These extruded products presented appropriate physical, phytochemical, and sensory characteristics, whose consumption has potential nutraceutical benefits.

Keywords: breakfast cereals, extrusion, carrot pomace, nutraceutical properties, sensory properties.