Heterocyclic acetals in Madeira wines

Area of Science:

• Food Chemistry
• Enology
• Organic Chemistry

Background:

• Madeira wine's characteristic aroma and flavor develop during high-temperature maturation.
• This process involves complex chemical changes affecting the wine's overall composition.
• Heterocyclic acetals are potential markers for aging in various food products.

Purpose of the Study:

• To investigate the formation and levels of heterocyclic acetals (1,3-dioxanes and 1,3-dioxolanes) in Madeira wines.
• To assess the potential of these acetals as indicators of wine age.
• To understand the influence of maturation conditions on acetalization.

Main Methods:

• Gas chromatography-mass spectrometry (GC-MS) was used to identify and quantify heterocyclic acetals.
• Analysis of Madeira wines of different ages.
• Correlation analysis between acetal levels and wine age.

Main Results:

• A linear correlation was observed between the levels of specific heterocyclic acetals and the age of Madeira wines.
• The formation of these acetals was found to be largely independent of the high-temperature oxidative conditions during maturation.
• 1,3-dioxanes and 1,3-dioxolanes were identified as key compounds of interest.

Conclusions:

• Heterocyclic acetals, particularly 1,3-dioxanes and 1,3-dioxolanes, can serve as reliable indicators of Madeira wine age.
• The acetalization process in Madeira wine is robust and not significantly hindered by oxidative maturation conditions.
• Quantification of these acetals offers a novel method for assessing wine aging.