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Aroma release from wines under dynamic conditions
Maroussa Tsachaki1, Robert S T Linforth, Andrew J Taylor
1Samworth Flavour Laboratory, Division of Food Sciences, Sutton Bonington Campus, University of Nottingham, Loughborough LE12 5RD, United Kingdom. maroussat@gmail.com
Journal of Agricultural and Food Chemistry
|July 16, 2009
Summary
Certain proteins disrupt aroma release from ethanolic solutions by affecting the air-liquid interface and convection. This impacts volatile compound headspace concentration, unlike in wine.
Area of Science:
- Food Science
- Analytical Chemistry
- Physical Chemistry
Background:
- Aroma compounds significantly influence wine quality and consumer perception.
- Understanding aroma release mechanisms is crucial for winemaking and quality control.
- Dynamic headspace dilution is a key technique for studying volatile compound behavior.
Purpose of the Study:
- To investigate the real-time aroma release from wines and model ethanolic solutions during dynamic headspace dilution.
- To identify factors influencing volatile compound headspace concentration in ethanolic systems.
- To elucidate the role of specific wine components, particularly proteins, in aroma release dynamics.
Main Methods:
- Real-time measurement of aroma release using atmospheric pressure chemical ionization-mass spectrometry (APCI-MS).
- Dynamic headspace dilution of model ethanolic solutions and wine samples.
- Analysis of volatile compound headspace concentration and interfacial surface temperature using thermal imaging.
- Inclusion of specific wine components (e.g., (+)-catechin, glycerol, proteins) in model solutions.
Main Results:
- Model ethanolic solutions maintained volatile headspace concentration near equilibrium during dilution, unlike wine samples.
- Acidity and common wine components (catechin, glycerol) did not affect volatile headspace concentration.
- Specific proteins (beta-lactoglobulin, beta-casein, bovine serum albumin) disrupted volatile headspace concentration maintenance.
- Thermal imaging indicated protein-induced disruption of the ethanol monolayer and Marangoni effect, impacting convection.
Conclusions:
- Certain proteins interfere with aroma release in ethanolic solutions by disrupting the air-liquid interface and convection.
- The Marangoni effect, driven by convection, plays a vital role in maintaining volatile compound concentration at the interface.
- These findings suggest a potential mechanism by which certain proteins in wine may influence aroma release.
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