Host: Japanese Sciety for Food Science and Technology
Name : The 72nd Annual Meeting of JSFST
Number : 72
Location : [in Japanese]
Date : August 27, 2025 - August 29, 2025
Purpose Underwater-aged wine is produced worldwide as a premium product. However, scientific evidence explaining flavor changes and their mechanisms during underwater aging is still lacking. We previously reported that 1,1-diethoxyethane (DEE), a fruity aroma compound not found in typical wines, is generated during underwater aging and causes distinct sensory changes. This suggests that underwater aging can create a unique flavor profile. In this study, we aimed to elucidate the mechanism of flavor change by focusing on the light that reaches underwater cellar and its role in DEE formation.
Methods The light spectrum reaching the underwater cellar was analyzed using a spectrometer and optical fiber. Subsequently, LED lights were used to reproduce the light of the underwater cellar and irradiate the wine model solutions.
Results Spectral analysis revealed that blue visible light peaking at 460 nm selectively reaches the underwater cellar. DEE was generated in the model solution at concentrations comparable to those in actual underwater-aged wine under blue light irradiation. In contrast, almost no DEE was formed under red light (625 nm) or in the dark. Comparative experiments showed that blue light, water, tartaric acid, iron, and oxygen were important for DEE formation. We propose that these factors promote a photo-Fenton reaction that generates hydroxyl radicals, which oxidize ethanol to acetaldehyde, followed by a condensation reaction with two ethanol molecules to form DEE. This light-focused approach successfully revealed part of the mechanism of flavor changes during underwater aging and may lead to new light-driven flavor enhancement technologies.