Sensory directed analysis for key odor-active compounds in by-products flavorings enhanced by enzymatic hydrolysis and Maillard reaction

Abstract

This study explores the enhancement of chicken bone flavor through enzymatic hydrolysis and the Maillard reaction, providing insights into the formation and characterization of key aroma compounds. Chicken bone extract was hydrolyzed using Protamex™ and Flavourzyme™ to obtain chicken bone enzymatic hydrolysate (CBEE), which was subjected to the Maillard reaction to produce Maillard reaction chicken flavoring (MRCF). The volatile compounds in CBEE and MRCF were comprehensively analyzed using solvent-assisted flavor evaporation (SAFE) and solid-phase microextraction (SPME) combined with two-dimensional gas chromatography–olfactometry–mass spectrometry (GC×GC-O-MS). A total of 40 odor active compounds were identified and their odor activity values (OAV) were calculated. Among them, 11 compounds contributed significantly to the overall aroma (OAV ≥ 1). Key contributors, including 2-methyl-3-furanethiol, furaneol, 5-(2-hydroxyethyl)-4-methylthiazole, and maltol, were confirmed through aroma recombination and omission experiments. The results highlight that the Maillard reaction significantly enhances the richness and complexity of the meaty and roasted aromas, driven primarily by the increased levels of sulfur-containing and heterocyclic compounds. This research provides a scientific foundation for the industrial development of meat flavorings from chicken bone by-products and offers valuable guidance for flavor optimization.