Structural characterization of resistant starch isolated from Laird lentils (Lens culinaris) seeds subjected to different processing treatments

This work focused on the structural characterization of resistant starch from untreated (UL-RS), germinated (GL-RS), fermented (FL-RS), microwaved (ML-RS), conventionally cooked (CL-RS), and autoclaved (AL-RS) lentil seeds. The size exclusion chromatography (SEC) results showed that UL-RS, RL-RS, and GL-RS (Group A samples) exhibited higher values of Mw and Rh¯ than FL-RS, ML-RS, AL-RS (Group C samples), and CL-RS (Group B sample). In parallel with the SEC result, other structural characteristics followed similar trends, where Group C samples exhibited the lowest values of double helix content and crystallinity by 13C NMR, and degree of order/double helix by FT-IR. Comparatively, Group A samples exhibited the opposite trends, and displayed large amorphous aggregates on their micrograph. The results are expected to provide information for better understanding the mechanism of resistant starch formation during different processing of lentil and to lay a theoretical foundation for the future study of their structure-function relationship.