Effect of non-covalent interactions on gluten-free batter stability and bread properties

Starch and proteins interact non-covalently by hydrogen bonding, electrostatic and hydrophobic interactions. While their impact on crumb stability in conventionally baked breads has been explored, the role of these interactions when using alternative baking technologies remains understudied. This study aimed to determine how non-covalent interactions affect rheological, nutritional and technological properties of gluten-free (GF) bread when baked using a deck oven or ohmic heating (OH). A GF formulation composed of maize starch and six structurally different non-gluten proteins was tested. Rheological and pasting properties, bread volume and starch digestibility were evaluated to study the significance of these interactions. Batter analyses indicated that protein functionality, particularly free sulfhydryl groups and surface hydrophobicity, strongly influenced pasting. Critical strain (0.09–0.14%) and flow transition points (1.01–3.69%) varied with protein type, showing distinct microstructural variations within the batter. Non-covalent interactions, especially hydrophobic and electrostatic forces, played a major role in stabilizing the OH bread, while conventional baking probably relied more on covalent interactions. Hydrogen bonding between polymers contributed to an increase in resistant starch (RS). This study revealed that specific non-covalent interactions played a crucial role in the structural and nutritional properties of GF bread, particularly when applying OH. • GF batters exhibited low critical strains and short linear viscoelastic regions. • Non-covalent interactions stabilized more predominantly ohmic baked breads. • Bread stability significantly relied on hydrophobic and electrostatic forces. • Hydrogen bonds in GF bread were crucial for the increase in resistant starch.