eng Oriental Scientific Publishing Company Biosciences Biotechnology Research Asia 0973-1245 2026-06-10 23 2 59039 article Subasshini Vaidyanathan 1 Pugazhmalar 1 Sufiya Fatheema Abdul Salam 1 PG Department of Home Science - Food Science, Nutrition, and Dietetics, ShrimathiDevkunvarNanalal Bhatt Vaishnav College for Women (Autonomous), Chennai, India Generational shifts and time constraints have driven consumer demand for convenient, nutrient-rich foods. Extrusion technology enables the creation of innovative functional snacks while preserving essential nutrients. This study aims to formulating a novel, nutrient-enriched extruded snack using underutilized grains such as Thooyamalli rice (Oryzasativa L) Horse gram (Macrotylomauniflorum(Lam) Verdc.), Prosomillet(Panicummiliaceum L.). Response Surface Methodology (RSM) was used to maximise important extrusion parameters, such as screw speed and barrel temperature, to evaluate multiple dependent variables such as physical properties and consumer acceptability. The optimized model exhibited a strong correlation with bulk density (R² = 0.7), expansion ratio (R² = 0.9), and overall sensory approval (R² = 0.8). The developed extruded snack demonstrated desirable textural attributes, including reduced hardness, enhanced crunchiness, and increased porosity. Microbial analysis confirmed its safety for consumption, and sensory evaluation yielded the highest acceptance score. Nutritional analysis has demonstrated statistically significant improvement (p < 0.05) in the nutritional composition of the snack in comparison with the control mixture (broken rice, soya flour, sorghum millet). There was an increase in protein, amounting to 48.96%; in dietary fiber – by 7.62%; phenols reached 34.21 mg/g ± 0.17; antioxidants are 33.91 mg/g ± 0.07, which demonstrates health advantages. The snack is richer in zinc than the control mixture, and it contains 6.53 mg/100g ± 0.04, which is 430.89% more than in the control sample. Moreover, there were increases in iron content by 194.02% and magnesium – 1547.22%. The balanced content of saturated and unsaturated fats contributes to the healthy properties of the snack. Stability test indicated microbiological and chemical safety during 30 days, which speaks in favor of sustainable nutrition. Overall, this innovation is aimed at promoting a healthy lifestyle and improving people's well-being. https://www.biotech-asia.org/vol23no2/formulation-and-optimization-of-millet-legume-extruded-snack-using-response-surface-methodology/ Bioactive compounds; Extruded snack; Extrusion cooking; Millet-based snack; Response surface methodology; Snack optimization