Volatile phenols depletion in red wine using molecular imprinted polymers
Rafaela Teixeira1, Sonia Dopico-García2, Paula B Andrade1
1REQUIMTE/Laboratório de Farmacognosia, Departamento de Química, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal.
Journal of Food Science and Technology
|November 26, 2015
Summary
Molecular imprinted polymers (MIPs) were developed to remove unwanted volatile phenols (VP) from wine, reducing off-flavors. While effective for specific compounds, further improvements in selectivity are needed for broader wine quality enhancement.
Area of Science:
- Food Chemistry
- Analytical Chemistry
- Polymer Science
Background:
- Wine aging can be negatively impacted by microbial spoilage, leading to the production of volatile phenols (VP).
- These off-flavors cause wine deterioration and significant economic losses, necessitating effective removal strategies.
Purpose of the Study:
- To develop and evaluate molecularly imprinted polymers (MIPs) for the selective removal of unwanted volatile phenols from wine.
- To assess the impact of MIP treatment on the overall phenolic profile and sensory characteristics of wine.
Main Methods:
- Two MIPs, MIP-4EG and MIP-4EP, were synthesized for targeted VP removal.
- Volatile compounds were analyzed using Gas Chromatography-Flame Ionization Detection (GC-FID) and Gas Chromatography-Ion Trap/Mass Spectrometry (GC-IT/MS).
- Phenolic compounds (non-colored and anthocyanins) were quantified via High-Performance Liquid Chromatography with Diode-Array Detection (HPLC-DAD).
Main Results:
- Treatment with MIP-4EG and MIP-4EP significantly reduced 4-ethylguaiacol and 4-ethylphenol levels, respectively.
- Analysis revealed changes in non-colored and colored phenolic compounds post-treatment.
- Sensory analysis indicated that while off-flavors were reduced, the specificity of the MIPs requires further optimization.
Conclusions:
- The developed MIPs demonstrate potential for reducing specific volatile phenol off-flavors in wine.
- Further research is necessary to enhance the selectivity and specificity of MIPs for comprehensive wine quality improvement.
- Optimizing MIPs could offer a viable solution to mitigate economic losses associated with wine spoilage by volatile phenols.
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