Production of Starch and Resistant Starch From Barnyard Millet by Enzymatic Method: Comparative Evaluation of Structural and Functional Characteristics

ABSTRACT The nutrient‐dense but underutilized barnyard millet ( Echinochloa frumentacea ) holds enormous potential for the creation of sustainable functional foods. This work investigates the enzymatic hydrolysis, debranching, and recrystallization of barnyard millet starch (BMS) to produce type 3 resistant starch (RS3). The study thoroughly assessed the structural, thermal, and functional properties of barnyard millet starch (BMS) and barnyard millet resistant starch (BMRS). Physical‐chemical testing revealed that BMS and BMRS were substantially different in terms of moisture content, swelling index, solubility, and amylose concentration. FT‐IR structural investigation revealed changes in the hydroxyl group arrangement, indicating that BMRS has more hydrogen bonds and crystallinity. According to FESEM, the smooth, round BMS granules changed morphologically into irregular BMRS granules with micropores and fissures. X‐ray diffraction showed a change from A‐type crystallinity in BMS to B‐type crystallinity in BMRS with observable peak fluctuations. Thermogravimetric analysis showed that BMRS was more thermally stable than BMS. These results establish a crucial structural, thermal, and functional relationship between BMS and BMRS, highlighting BMRS's potential as a functional ingredient for nutraceutical applications, offering improved thermal and enzymatic stability suitable for health‐promoting dietary solutions.