Snacks are a popular choice for various consumers. Corn Grits’ (CG) high starch content makes it an ideal choice for producing extruded snacks with excellent expansion properties. However, corn-based extruded products lack essential nutrients. Confectionery sunflower seeds kernel (CSSK) are an economical option for producing protein-enriched food products. This study aimed to investigate the production of an expanded snack based on CSSK-CG using extrusion technology. The effects of extrusion process variables, including CSSK level (7-21%), feed moisture (12-18%), and screw speed (120-220 rpm), on certain characteristics of the expanded snack were examined using response surface methodology (RSM) and BoxBehnken design. The characteristics analyzed included final moisture content, water absorption index (WAI), water solubility index (WSI), and porosity. The final moisture content, WAI, WSI, and porosity of the extruded products ranged from 4.49 to 7.62%, 1.26 to 4.04 g/g, 11.39 to 19.76%, and 24.61 to 78.88%, respectively. It was observed that increasing feed moisture and screw speed resulted in higher final moisture content in the extruded product. Feed moisture acted as a plasticizer in the extrusion process, reducing starch degradation and increasing the WAI. Feed moisture and screw speed respectively decreased and increased the WSI. Increasing CSSK level reduced porosity, with the lowest porosity (0.6124) associated with the highest CSSK level (21%). SEM images showed increasing CSSK levels from 7 to 21% increased the number of air cells and the thickness of cell walls.

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