This study elucidated the relationships among structure, functionality, and digestibility of durum wheat starches (DWS) across a wide range of amylose content. DWS1–6 with 36.6%–65.7% apparent amylose were isolated from six durum wheat lines, which were extensively characterized and compared with a commercial normal wheat starch (NWS). As the amylose content and the proportion of amylopectin long branch chains (LBC) increased, X-ray diffraction patterns transitioned from A-type (NWS and DWS1) to C-type (DWS2–3), and eventually to B-type (DWS4–6). These structural changes led to progressive increases in gelatinization temperatures and retrogradation rates from DWS1 to DWS6. Under 95 °C–140 °C heating in Rapid Visco Analyser (RVA 4800), NWS and DWS1–6 exhibited three distinct pasting behavior patterns: normal- (NWS and DWS1), intermediate- (DWS2–3), and high-amylose groups (DWS4–6). Resistant starch (RS) content gradually increased from DWS1 to DWS6 in a raw state; notably, high-amylose DWS6 maintained the highest enzymatic resistance even after cooking. Principal component analysis (PCA) classified DWS1–6 into three distinct sub-groups: normal- (DWS1), intermediate- (DWS2–3), and high-amylose (DWS4–6) groups. The new understanding of the structure-function-digestibility relationships in DWS offered valuable insights for the agri-food industry to develop novel starch and semolina ingredients with tailored functional and nutritional properties from diverse durum wheat lines.
Ren et al. (Sun,) studied this question.