Fermentation strategies in mead production: A multitechnique volatilomic approach to aroma characterization

This study compares spontaneous and yeast-inoculated mead fermentations, analyzing their effects on sensory and chemical profiles. Using advanced instrumental techniques: untargeted analysis of odorants, quantitation of odor-active compounds, and flow cytometry-this research identifies key fermentation-driven changes. Untargeted analysis revealed a more complex volatile profile in spontaneous fermentation, with a higher number of unique compounds (27) from groups classified as fruity (esters), spices (ex. pentane-2,3-dione) and off-flavors (2-furanyl)methanol, octan-1-ol, ethyl 3-methylsulfanylpropanoate, 2-phenylacetonitrile, dodecan-1-ol, 3-methylpentanoic acid, and 3-methyl-1H-indole). Yeast-inoculated samples were characterized by only 8 unique compounds, with more predictable odor profile and fewer off-flavors (2-pentylfuran, pyridine, (E)-oct-2-enal). Statistical analysis identified distinct compounds linked to fermentation type and stage, with microbial dynamics influencing odor-active compound formation. Bacterial content correlated with ethyl hexanoate (0.63), furan-2-carbaldehyde (0.33), and phenylacetic acid (0.49), while yeasts displayed correlations with 2-phenylacetaldehyde (0.37), ethyl hexanoate (-0.59), phenylacetic acid (-0.50), and furan-2-carbaldehyde (-0.47).