Product Development of Nutritious Rice Based Gluten-Free Snacks from Different Formulation of Rice Varieties by Extrusion and their Physical, Physicochemical and Sensory Evaluation

Flour from three high-nutritional rice varieties were used to produce gluten-free extruded rice snacks. This study investigated the optimal formulation of the flour mixes from brown jasmine rice (JR) and two other pigmented varieties brown black glutinous rice (BGR) and brown riceberry rice (BB) to produce the extruded snack. Chemical compositions, including dietary fiber and antioxidants of each rice variety were determined. Ten formulations of the flour mixes were evaluated using a Mixture Design and extruded via a single-screw extruder. The physical properties of the extruded snacks from each formulation such as expansion ratio, color, hardness and crispness, as well as their physicochemical properties, including water absorption and solubility indices were analyzed. Three flours showed high protein content (8.1–9.0%). Both pigmented rice (BGR and RR) indicated a higher DPPH scavenging activity at 0.51 ± 0.05 μmol Trolox/g dry weight (DW) and 0.25 μmol Trolox/g DW, respectively. BGR showed the highest % DPPH inhibition (31.63 ± 0.32%). The snack indicated the highest expansion ratio with brown riceberry rice, followed by jasmine rice and brown black glutinous rice. The use of flour mixes indicated higher overall liking scores than one specific flour, while the mixing ratio of jasmine rice, brown black glutinous rice and brown riceberry at 1: 1: 1 (Formulation 7) tended to achieve the highest overall liking (6.47 from 9 points hedonic scale) and the high scores for most of the sensory attributes. The total dietary fiber of the snacks from Formulation 7 was around 4.11% by weight. The results revealed the high potential for using brown jasmine rice and pigmented rice to extrude gluten-free rice snacks.