REMEDIATION OF SMOKE TAINTED WINE USING MOLECULARLY IMPRINTED POLYMERS
In recent years, vineyards in Australia, the US, Canada, Chile, South Africa and Europe have been exposed to smoke from wildfires. Wines made from smoke-affected grapes often exhibit unpleasant smoky, ashy characters, attributed to the presence of smoke-derived volatile compounds, including volatile phenols (which occur in free and glycosylated forms). Various strategies for remediation of smoke tainted wine have been evaluated. The most effective strategies involve the removal of smoke taint compounds via the addition of adsorbent materials such as activated carbon, which can either be added directly or used in combination with nanofiltration. However, these treatments often simultaneously remove wine constituents responsible for desirable aroma, flavour and colour attributes.
This study sought to evaluate molecularly imprinted polymers (MIPs) as a novel adsorbent developed specifically to target the removal of smoke-derived volatile phenols from wine. MIPs were initially added to a smoke tainted Pinot Noir wine, and their capacity to remove volatile phenols (by 40 to 50%) demonstrated by gas chromatography-mass spectrometry analysis of wine before and after treatment. A semi-commercial scale trial was subsequently undertaken and involved passing smoke tainted Chardonnay, rosé and Cabernet Sauvignon wines through a column packed with MIPs. The impact of treat-ment was evaluated by comparing the colour, volatile phenol composition and sensory profiles of wines, before and after treatment. Findings from this study afford winemakers valuable insight into the potential for MIPs to be used as a novel additive for the remediation of smoke tainted wine. Results from a kinetic study comparing the binding efficacy of different volatile phenols to MIPs will also be presented
Issue: OENO Macrowine 2023
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smoke taint, volatile phenols, volatile phenol glycoconjugates, wine sensory