Abstract
Background: Omics techniques—which comprehensively profile the metabolites present in foods—are increasingly applied as objective tools for evaluating raw materials, processed products, palatability, functionality, safety and quality. Bread aroma is a decisive driver of consumer choice, yet the spatial fate of flavor-active volatiles in the minutes after baking has never been comprehensively mapped. Previous studies, which are limited to one-dimensional GC or targeted assays have confirmed that Maillard and caramelization pathways dominate aroma formation, but they leave unanswered how those compounds migrate between crust and crumb during cooling. To close this gap, we applied a non-targeted VOC-omics workflow to freshly baked wheat loaves, characterizing time-dependent migration behavior of bread aroma.
Methods: After baking, a loaf of bread was cooled and its crust and crumb were sampled. Two-gram portions of each sample were placed in an MPS Robotic Pro system to trap volatile compounds, which were then thermally desorbed, concentrated and injected into a Pegasus BT-4D GC×GC-TOFMS for two-dimensional separation. The resulting chromatograms were aligned and tentatively identified with ChromaTOF Tile software using the NIST and Wiley libraries, producing a data matrix. Multivariate analyses were carried out with JMP Pro 17 and R.
Results: By combining a non-targeted omics workflow with multivariate statistics, the study clarified the time-dependent odor profiles that migrate from freshly baked bread and can potentially offer data-driven strategies for designing sensory tests, shelf-life studies and formulation.
