Development and characterization of multi-millet extruded food snack

Millets are nutrient-dense, small-seeded crops, but receive an undervalued response in the snacks manufacturing industry. Therefore, this research aims to formulate healthy and nutrient-dense extruded snacks by optimizing the composition of different millets (Foxtail, Kodo, and Proso) at varying levels—100, 25, 50, and 33% (w/w) using twin-screw extrusion processing. The process parameters, including barrel temperature 110 ℃, pressure 15 PSI, feed rate 4 kg/h, and feed moisture (20 and 25%), remain constant. The physico-mechanical characterization and sensory properties were analysed to assess the quality of the extrudates. The results showed that the density of extruded product ranged from 0.30 to 0.50 g/cm³, expansion ratio from 1.24 to 1.78%, water absorption index from 3.27 to 5.11 g/g, and water solubility index from 2.97 to 6.80%. The FTIR spectra displayed the peak ranges of OH, C-H, N–H, C = O, and C-NH bonds in the processed products. XRD data reported the A- and V-type starch crystallinity of the processed product. Mineral analysis of millet extrudates showed that the significant presence minerals, while heavy metals were not found. The extruded product exhibited a reddish yellow colour with good sensory characteristics. These results highlighted the potential of millet blends in the production of nutrient-dense extruded snack products.