Extrusion cooking of gluten‐free whole grain flour blends

Whole grain flour blends from maize, rice, and sorghum were processed in a single screw extruder to produce puffed snacks and the physical properties of the extrudates were determined. Blends from sorghum or maize at high proportions (70%) produced extrudates with low expansion, high apparent density, and small and uniformly distributed air bubbles in their structures that affected texture. Suspensions rich in sorghum reduced setback viscosities. Extrudates produced from equal proportion of maize, rice, and sorghum presented low compression forces and minimum crispness work, whereas blends with high proportion of sorghum affected these textural responses negatively. The choice of a blend of equal proportion of whole grain flours of those three components would allow to produce nutritious puffed snacks with relatively higher dietary fiber content, provided by maize and sorghum, higher protein content by sorghum component, and higher crispness by rice. Practical applications The use whole grains is growing in gluten‐free products, due to the benefits of its components (dietary fiber, phytochemicals, protein, vitamins, and minerals) which make them attractive raw materials for designing new alternative foods with health benefits. Gluten‐free cereals: maize, rice, and sorghum are available sources in the Americas, particularly in Brazil and in the United States. The thermoplastic extrusion is a cooking technique that allows the combination of heat and shear causing unique changes to the textural properties of the final product. Therefore, whole grain flours with appropriate modulation of the extrusion parameters can be used to create fiber rich cereal products. The use of gluten‐free whole grain flours blends includes ready‐to‐eat dietary fiber rich snacks (puffed extrudates) and, with appropriate milling, it could also be used as ingredient for baking applications, dehydrated instant foods (porridge), cereal beverages, as well as for other innovative applications in the food industry.