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This study explores the impact of ohmic heating, a non-chemical, electric field-driven thermal process, on sorghum starch. Two sorghum genotypes with different amylose contents (85P20: 35.6%, 81G67: 24.5%) were subjected to various electric field strengths (25–70 V/cm) to assess physicochemical changes and the formation of resistant starch (RS). Techniques like FTIR and XRD revealed that ohmic heating induced partial gelatinization, disrupted crystallinity, and caused molecular reorganization, even at low moisture levels (1:1 w/w). FTIR showed shifts in O–H and water-associated bands, suggesting reconfiguration of hydrogen bonds, while XRD confirmed reduced starch crystallinity. Significantly, RS content increased with higher field intensity, indicating enhanced retrogradation and amylose-inclusion complex formation. This method produces resistant starch without chemical additives, offering a sustainable approach to developing functional starches for health-oriented food applications. By adjusting electric field parameters, starch digestibility and functionality can be tailored for clean-label products.