The effect of formulation on physiochemical and functional properties of extruded breakfast cereals was investigated. The anthocyanins of breakfast cereals were quantified using HPLC, and remarkable retention of anthocyanins and antioxidant properties was recorded. The purple sweet potato (PSP) indicated a most significant positive impact on antioxidant capacity, whereas the cornflour contributed toward a better expansion of the final product. The optimum formulation of breakfast cereal with an acceptable textural properties and highest antioxidant properties was produced using 55% PSP powder, 15% whole red rice flour, and 30% cornflour and resulted breakfast cereals with hardness, SEI, antioxidant activity, anthocyanin, and total phenolic content of 4.87 kg, 2.93, 13.57 mu mol TE/g, 66.35 mg/100 g and 5.13 mg GAE/g, respectively, with attractive natural color, satisfactory bowl-life and better functional properties. PSP and red rice provide natural color to the final product and rich source of anthocyanins with better antioxidant capacity. Novelty impact statement The results obtained in this study reveals the potential use of purple sweet potato, whole red rice, and cornflour to formulation of healthy extruded breakfast cereals using a D-optimal mixture design approach, and resulted breakfast cereals showed better expansion, texture, bowl-life, and rich in the natural bioactive compound, fiber, and colorants.
