Molecular insights into the interactions between wine aroma compounds and soluble fractions of specific yeast derivatives: A spectroscopic study

Abstract

Yeast derivative products (YDP) are increasingly used in winemaking for their impact on sensory properties, yet their molecular interactions with wine aroma compounds remain poorly understood. This study investigated the binding mechanisms between soluble fractions of specific mannoproteins and yeast protein extracts with selected wine aroma compounds (β-damascenone, β-ionone, citral, and benzaldehyde) using fluorescence spectroscopy in model wine conditions. Soluble fractions were separated by molecular weight (< and > 10 kDa) to evaluate their specific contributions to aroma interactions. Steady-state fluorescence quenching revealed that only specific aroma compounds (β-damascenone, β-ionone, citral, benzaldehyde, and 4-ethylphenol) modified protein fluorescence, suggesting selective interactions with tryptophan residues. Stern-Volmer analysis confirmed static quenching mechanisms through complex formation, with binding constants ranging from 103 to 104 M⁻¹. Molecular weight fractionation demonstrated that the higher MW fraction (> 10 kDa) of the studied mannoproteins > 10 kDa exhibited the strongest binding affinity, while both high and low molecular weight fractions of the studied yeast protein extract showed significant interactions with tested aroma compounds. Hydrophobicity was identified as a key factor governing binding selectivity, with cyclic compounds (β-damascenone, β-ionone) showing stronger affinity than linear aldehydes. A blue shift in fluorescence emission spectra observed with β-ionone indicated specific interactions leading to increased hydrophobicity around tryptophan residues. Furthermore, ethanol concentration significantly modulated interactions with hydrophobic compounds, potentially by altering aroma solubility and protein conformation. These results provide a fundamental basis for understanding how the macromolecular composition of a yeast derivative can modulate the volatility and retention of key enological aromas.

References

L. Favieres, M. Bastien, C. Poncet-Legrand, T. Doco, A. Vernhet, T. Godet, V. Nolleau, S. Roi, S. Carrillo, N. Sieczkowski, J. Mekoue, P. Rigou. Exploring the impact of yeast derivatives on aromatic and sensory profiles of white and red wines: a multifactorial study (2025), OENO One, 59(3), 9264.