Decoding the Aroma Gap: Sensomics-Based Characterization of Key Odorants in the Plant-Based Egg and Chicken Egg

Abstract

This study presents the first molecular-level comparative analysis of chicken scrambled eggs and vegan scrambled eggs, identifying a total of 20 odorants using Aroma Extract Dilution Analysis (AEDA). Quantitation via Stable Isotope Dilution Assay (SIDA) and calculation of dose over threshold (DoT) factors revealed 15 key odorants with DoT factors > 1 in scrambled chicken eggs, while scrambled vegan eggs exhibited 11 key odorants with DoT factors > 1. Notably, the vegan product lacked five critical compounds: (E,Z)-2,6-nonadienal (cucumber-like), 2,3-butanedione (butter-like), (E)-2-nonenal (fatty), 4-methylphenol (smoky), and 2,3-diethyl-5-methylpyrazine (earthy), while it displayed a higher odor activity for 1-octen-3-one (mushroom-like), hexanal (grassy), 3-methylbutanoic acid (sweaty), and trans-4,5-epoxy-(E)-2-decenal (metallic-like). The aroma reconstitution experiment confirmed that key odorants of scrambled chicken egg aroma were successfully decoded. Omission experiments further highlighted that even in the absence of hydrogen sulfide, the characteristic aroma of scrambled chicken eggs can be best presented by only six odorants: (E,Z)-2,6-nonadienal, 2- and 3-methylbutanal (malty), 3-(methylsulfanyl)propanal (cooked potato), 2,3-butanedione, and 1-octen-3-one. These findings provide a foundational framework for optimizing the aroma of plant-based egg alternatives.