Valorization of whole-grain Peruvian Andean maize varieties through extrusion cooking into snacks and pregelatinized flours

Carvalho H.J.M.; Wuchner A.A.; Cirino M.S.; Nolasco M.V.F.M.; de Campos J.P.C.G.; da Silva D.A.D.; Salvador-Reyes R.; da Silva S.X.; Junior M.R.M.; Nabeshima E.H.; Clerici M.T.P.S. · Applied Food Research (2026) · DOI: 10.1016/j.afres.2026.102610

Resumen

Peruvian Andean maize varieties are traditional grains with distinctive technological, nutritional, and bioactive properties, but their use in ready-to-eat products remains limited. This study evaluated four whole-grain Peruvian Andean maize varieties, Chullpi, Morado, Piscorunto , and Sacsa , to produce extruded snacks and pregelatinized flours using a co-rotating twin-screw extruder. The products were characterized according to extrusion behavior, technological properties, microstructure, pasting profile, hydration properties, color, phenolic compounds, and antioxidant capacity. Piscorunto and Sacsa showed higher torque, 41.0 and 37.0%, and specific mechanical energy, 138.1 and 133.2 W·h/kg, respectively. These varieties produced snacks with greater expansion indices, 2.71 and 2.65, higher porosity, 46.39 and 40.99%, and lower bulk density, 0.20 and 0.34 g/cm³, respectively. In contrast, Chullpi and Morado generated denser and more compact matrices, with expansion indices below 1.0 and bulk densities above 1.0 g/cm³. Microscopy revealed extensive starch disruption after extrusion, although residual birefringent starch granules indicated partial preservation of the semicrystalline structure. Pregelatinized flours showed markedly lower peak viscosities than raw flours, decreasing from 979 to 3111 cP to 158–409 cP, confirming substantial starch transformation during extrusion. Morado exhibited the highest phenolic content and antioxidant capacity, whereas extrusion increased ORAC values in Chullpi, Piscorunto , and Sacsa , suggesting a genotype-dependent release of antioxidant compounds and/or formation of Maillard reaction products. Overall, extrusion cooking is a promising strategy to valorize whole-grain Andean maize into differentiated snacks and pregelatinized flours.

Instituciones: Universidad Tecnológica del Perú