Influence of different cell wall disruption methods on flavor quality of yeast extract: mechanistic insights through peptidomics and molecular docking.

Yeast extract (YE) is a widely used natural flavor enhancer whose taste and aroma quality govern its industrial value. However, how the cell wall disruption method, the first and decisive step of YE production, shapes flavor at the molecular level remains unclear, leaving method selection largely empirical. In this study, five representative disruption methods, autolysis (AY), ethyl acetate chemical disruption (EA), high-pressure homogenization (HPH), low-temperature colloid milling (LCM), and glucanase enzymatic hydrolysis (GE), were systematically compared using sensory evaluation, electronic nose and tongue, free amino acid and nucleotide profiling, solvent-assisted flavor evaporation coupled with gas chromatography-olfactometry-mass spectrometry (SAFE-GC-O-MS), electroencephalography (EEG), liquid chromatography-tandem mass spectrometry (LC-MS/MS) peptidomics, and molecular docking. Results showed that GE produced the highest umami amino acid content (113.01 mg/g DW, p < 0.05) and the lowest bitterness, whereas EA yielded the highest bitter amino acid proportion; SAFE-GC-O-MS identified 117 volatile compounds, of which 67 (odor activity value ≥1) drove inter-group differentiation, and peptidomics revealed 1785 differential peptides, with GE generating more glutamate/aspartate-rich umami-associated peptides. In addition, molecular docking demonstrated that GE-derived acidic peptides bound the umami receptor T1R1/T1R3 most strongly (ΔG down to -9.18 kcal/mol), whereas EA-derived hydrophobic peptides preferentially engaged the bitter receptors TAS2R13/TAS2R14; synthesized-peptide validation corroborated these predictions (r = 0.93). Therefore, entropy-weighted TOPSIS confirmed the ranking GE > LCM > HPH > EA > AY, and this study establishes a "disruption method to peptide profile to receptor selectivity to flavor quality" framework guiding the industrial production of high-quality YE.