Relation between quality characteristics of wheat flour and in vitro starch digestibility of dried noodles: Insights from noodle structure.

This study aimed to elucidate the relationships between quality characteristics of wheat flour and in vitro starch digestibility of dried noodles. Seven commercially available wheat flours were selected to prepare dried noodles. The quality of the wheat flours, along with the structure of gluten proteins and starch in noodles during and after complete rehydration, and in vitro starch digestibility were investigated. Results showed that flours with higher wet gluten content (>29.35), gluten index (>90.06), and swelling index of glutenin (SIG, >5.06) led to the aggregation of gluten proteins into macropolymers, forming a compact gluten network in cooked noodles. Simultaneously, the molecular ordering of gelatinized starch in these noodles is more ordered. The molecular interactions between protein and starch facilitate the formation of a compact starch-protein composite gel structure, which limit the rate of starch digestion (9.57 × 10 to 10.01 × 10 min). Overall, this work demonstrates that wheat flour with high wet gluten content and gluten index can effectively modulate starch digestibility in noodles by altering the formation and structure of the starch-protein composite gel matrix.