Elucidating the adsorption mechanisms of yeast extract on trimethylamine and dimethylamine based on multi-spectroscopic techniques and molecular docking

The presence of off-flavor compounds in meat products significantly diminishes their sensory quality. In this study, two amine off-flavor compounds, trimethylamine (TMA) and dimethylamine (DMA), were employed as examples to investigate the behavior of yeast extract (YE) in absorbing off-flavors using gas chromatography–mass spectrometry. Additionally, the effects of TMA and DMA on YE conformation were explored based on multi-spectroscopic techniques and molecular docking to elucidate the mechanism of YE adsorption of off-flavors. The results revealed that YE exhibited strong adsorption capabilities towards both TMA and DMA, with a higher affinity for DMA. The presence of TMA and DMA unfolded the YE structure, accompanied by an increase in total sulfhydryl content and zeta potential and a decrease in surface hydrophobicity and particle size of YE. Furthermore, TMA and DMA disrupted the hydrogen-bonding network of YE, causing it to shift from an ordered to a disordered structure. Thermodynamic parameters and molecular docking indicated that YE primarily adsorbed TMA and DMA through hydrogen bonding and van der Waals forces. This study provided valuable insights for utilizing YE in the inhibition of off-flavors in meat products.