Exploring the impact of dietary fiber enrichment on molecular water properties and indicators of Maillard reaction (furosine, Nε-carboxymethyllysine, and Nε-carboxyethyllysine) in model gluten-free bread

This study aims to simultaneously monitor three key indicators of the Maillard reaction (furosine, N-ε-(carboxymethyl) lysine (CML) and N-ε-(carboxyethyl) lysine (CEL)) in the crust and crumb of gluten-free bread enriched with various commercial fiber preparations (apple, cocoa, blackcurrant, chokeberry, oat, and potato) and the low-field NMR analysis of water behavior, its activity and transport model. The results indicate that fiber preparations with varying compositions alter water binding and its molecular dynamics, thereby modulating the Maillard reaction environment. The differences between the spin-spin (T2) and spin-lattice (T1) relaxation times values in crust and crumb were due to the migration of some water out of the system. In comparison to reference bread, chokeberry and blackcurrant fiber preparations not only affected water mobility but also contributed to a significantly higher content of CML in crust samples (83.9 % and 54.4 %, respectively) and crumb samples (31.9 % and 71.2 %, respectively).