Second-generation snacks with high nutritional and antioxidant value produced by an optimized extrusion process from corn/common bean flours mixtures

Abstract

Snacks directly expanded (second-generation) are trendy in the market, but considered products of poor nutritional due to usually made with corn starch. In this research, optimization of the extrusion process variables and the bean flour inclusion level was carried out to develop optimized expanded snacks (OES) with high nutritional/antioxidant value from corn/common bean flours mixtures. Physicochemical, nutritional, antioxidant, and phytochemical characterization of OES also was realized. The optimization resulted in four different conditions to obtain OES. The OES had acceptable values of expansion ratio (ER) (1.86–2.29), hardness (H) (4.85–6.88 N), and bulk density (BD) (0.168–0.225 g/cm3). The optimal conditions used to produce OES increased antioxidant activity (AoxA) (ABTS: +9.7–20.8%, DPPH: +13.4–19.4%, FRAP: +1.6–9.4%), total phenolic content (TPC) (+4.5–8.9%) and melanoidins content (MC) (+20.6–98.4%) respect to the unprocessed grains mixtures. A 50 g portion of OES had a high protein content (3.1–4.7 g), total dietary fiber (4.4–5.4 g), TPC (139–162 mg Gallic acid equivalents), MC (205–232 mg), AoxA (3574–4180 μmol Trolox equivalents) and low energy (183–185 kcal). Due to its high nutritional and antioxidant value, the OES produced from corn/common bean flours mixtures could be used for the promotion of health and the prevention of chronic diseases.