Characterization of Low-Alcohol Wines Obtained by Post-Fermentative Reverse Osmosis and Vacuum Concentration

Area of Science:

• Enology
• Food Science
• Sustainable Winemaking

Background:

• Growing demand for healthy lifestyles and climate change impact wine production.
• Reducing alcohol content in wine while maintaining quality is a significant industry challenge.

Purpose of the Study:

• To evaluate two dealcoholization techniques for producing quality low-alcohol wines (LAWs).
• To compare the compositional and sensory impacts of reverse osmosis followed by vacuum concentration (ROVC) and two-step vacuum concentration (TSVC) on Muscat Ottonel wine.

Main Methods:

• Muscat Ottonel wine was processed using ROVC and TSVC at different alcohol concentrations (3.50%, 5.50%, 8.50% vol).
• Compositional analysis included organic acids, volatile compounds, phenolics, and color intensity.
• Sensory properties and antioxidant activity were evaluated.
• Hierarchical cluster analysis compared LAWs to conventional wine.

Main Results:

• Both ROVC and TSVC altered wine composition and sensory profiles, with effects varying by alcohol reduction and technique.
• ROVC resulted in decreased organic acids, volatile constituents, extract, and color intensity as alcohol content lowered.
• TSVC LAWs exhibited higher phenolic content, antioxidant activity, and volatile compounds (esters, terpenes), maintaining better wine typicity and structural balance.
• Alcohol reduction below 5.50% vol. significantly impacted overall quality and acceptability for both methods.
• TSVC LAWs were found to be compositionally closer to conventional wine.

Conclusions:

• TSVC is a more effective method for producing quality low-alcohol wines that retain key characteristics of conventional wine.
• Understanding dealcoholization technology impacts is crucial for improving wine quality, sustainability, and operational efficiency.
• Further research into optimizing dealcoholization processes is recommended for the wine industry.