Effects of extrusion process in snacks of oats–nixtamalized corn pericarp mixtures on dietary fiber content and functional properties

Abstract

The aim this work was to establish the best conditions to increase the soluble dietary fiber (SDF), evaluate the effect of extrusion on the SDF, and insoluble dietary fiber (IDF), in a snack obtained by extrusion, that serve as a source of calcium and DF, using mixtures of oat–corn pericarp. The corn pericarp was obtained from byproduct of nixtamalization process which contains water, calcium hydroxide, soluble solids, and pericarp. The studied parameters were temperature (120–140°C), moisture (200–400 g/kg), and corn pericarp (200–400 g/kg); the responses were expansion ratio, SDF, IDF, and water absorption index (WAI). The R 2 were > 0.85 for all factors. The best conditions were temperature (133°C), moisture (230 g/kg), and corn pericarp (300 g/kg), with responses of 93.1 g/kg increase in SDF, 60 g/kg decrease of IDF, expansion of 1.26, WAI of 4.12 g sediment/g dry solid, and calcium content 4350 mg/kg.