Selective methods for polyphenols and sulphur dioxide determination in wines

Area of Science:

• Oenology
• Analytical Chemistry
• Biosensors

Background:

• International methods for wine analysis are reviewed, highlighting industry and research practices.
• Polyphenols significantly impact wine stability and sensory characteristics.
• Sulphur dioxide (SO2) is a key wine additive with analytical challenges.

Purpose of the Study:

• To critically review existing wine analysis methods.
• To apply a laccase biosensor for selective o-diphenol determination in wines.
• To propose a new parameter, IBP/SO2, for evaluating wine quality and benefits.

Main Methods:

• A laccase biosensor was utilized for polyphenol determination (IBP).
• Spectrophotometric methods were employed for free and total sulphur dioxide (SO2) analysis.
• ABTS(+) assay measured antioxidant capacity; correlation studies were conducted.

Main Results:

• The biosensor showed selective response to o-diphenols, key wine polyphenols.
• High correlation was observed between the biosensor polyphenol index (IBP) and antioxidant capacity.
• Low correlation was found between SO2 concentration and antioxidant capacity.

Conclusions:

• The laccase biosensor is effective for assessing wine polyphenols.
• Polyphenols are strongly linked to antioxidant capacity, influencing wine quality.
• The proposed IBP/SO2 ratio offers a new metric for wine benefit evaluation.