Berry Powder-Enriched Gluten-Free Extruded Snacks: Nutritional Quality and Antioxidant Potential

The increasing prevalence of celiac disease underscores the need to develop nutritionally balanced, gluten-free snacks based on local raw materials. This study aimed to develop extruded gluten-free snacks based on corn, rice, buckwheat, and chickpea flours, enriched with a 5% blend of berry powders (sea buckthorn, blackcurrant, cranberry), and to evaluate their physicochemical, nutritional, and antioxidant properties. Snacks were produced via high-temperature short-time extrusion (120–160 °C). The results demonstrated that chickpea/corn formulations exhibited the highest initial protein content (13.87%), which remained robust after berry addition (9.14%), outperforming the starchy corn/rice control (7.61%). Enrichment significantly enhanced the functional profile: water-soluble antioxidants increased from 0.039 to 0.60–0.71 mg/g, and DPPH radical scavenging activity reached up to 61.8 ± 2.4%. Furthermore, the enriched snacks exhibited high retention of thermolabile compounds, including Vitamin C (up to 18.91 mg/100 g). Sensory evaluation confirmed excellent organoleptic acceptability without compromising texture. These findings quantitatively demonstrate that combining legume flours with berry powders enables the production of gluten-free extruded snacks with improved protein density, superior antioxidant potential, and moderate energy value (322–330 kcal/100 g), offering a functional alternative for specific dietary needs.