Dairy-Derived Aroma Release Modulated by Oral Mucin: In Vitro Study Insights from Multispectral, Computational Modeling, and Machine Learning

Salivary mucin plays a pivotal role in modulating aroma
perception
during dairy consumption. This study investigated the impact of mucin
on the release of ten key milk fat-derived aroma compounds (including
3 aldehydes, 3 ketones, and 4 lactones) using headspace solid-phase
microextraction-gas chromatography–mass spectrometry (HS-SPME-GC–MS).
The results demonstrated that mucin significantly inhibited the release
of most compounds, including 2-heptanone, 2-nonanone, 2-pentadecanone,
heptanal, δ-hexalactone, δ-octalactone, and δ-decalactone,
with a maximum binding percentage of 34.79 ± 9.63%. Sensory analysis
confirmed perceptible differences. Thermodynamic and spectroscopic
data revealed that the binding was spontaneous and primarily driven
by hydrophobic interactions and hydrogen bonds involving phenylalanine
and tyrosine residues, which induced significant conformational changes
in the mucin secondary structure. Shapley additive explanations analysis
based on the support vector regression model identified the number
of H-bond acceptors as the most critical molecular feature. These
findings provide insights for modulating aroma perception in dairy
products.