Insights into the textural characteristics and in-vitro digestibility of bread influenced by structures and properties of high-amylose corn starches

High-amylose corn starch (HACS) has crucial impacts on the textural characteristics of dough, but the molecular mechanism remains unknown. This study aims to explore how the structures of HACS with various apparent amylose contents (55.92%–71.66%) affected dough fermentation properties, textures and in-vitro digestibility of breads. Results showed that debranched HACS had low proportions of fa chains (DP 6–12) and high proportions of fb 1 chains (DP 13–24). More short fa chains were associated with decreased bread hardness, while more amylose chains with DP 100–1000 were associated with increased hardness. HACS addition reduced the maximum dough height and total gas production, but increased the carbon dioxide (CO 2 ) retention in the dough. Breads enriched with 40% HACS had higher resistant starch contents and lower estimated glycemic indexes (51.32–60.04) than the control bread (69.92). Although the rise in HACS levels increased hardness, it could serve as a vital alternative to white bread. • High-amylose corn starch delayed dough development and enhanced gas retention. • Decreased bread hardness was associated with more short fa chains (DP 6–12). • Increased bread hardness was correlated with more short amylose chains (DP 100–1000). • Bread enriched with 40% high-amylose corn starch exhibited a lowered estimated glycemic index.