Substitution of rice flour with rice protein improved quality of gluten-free rice spaghetti processed using single screw extrusion

Rice protein (RP) has attracted interest as a hypoallergenic protein. In this study, RP was used to improve cooking quality, physicochemical properties, and sensory attributes of gluten-free rice spaghetti (GFRS). GFRS samples were developed by replacing rice flour with rice protein concentrate at 0% (control), 2.5%, 5.0%, 7.5% and 10% (w/w), processed through a single screw extruder. Pasting properties and gel texture of rice flour, protein content, microstructure, cooking quality, texture properties, and sensory attributes of GFRS were determined and compared with GFRS without RP and wheat spaghetti. Substitution of rice flour by 5%-10% RP significantly decreased cooking time and cooking loss. GFRS with 5%-10% RP was more porous than GFRS without RP. Sensory evaluation showed that GFRS containing 2.5% and 5% RP had a high overall linking score which was comparable with wheat spaghetti. Results suggested that RP showed potential to improve the cooking quality and physicochemical properties of GFRS with high acceptability.