CRAG And The Cork Industry Work Together To Preserve Wine Quality

A genomics approach to the problem of the corked wine aroma

• A research team at CRAG collaborates with the cork company Francisco Oller SA to address the problem of the corked wine aroma.
• Researchers compared the gene activity of different populations of cork oaks and identified several compounds that may cause this problem.
• This collaboration, within the Cork2Wine project, has brought fundamental research solutions to the current needs of society.

Spain produces 50% of the world's cork and 30% of all cork stoppers. Cork is a natural polymer which has been a crucial element used to seal bottles, being of great importance for the wine industry. However, a major challenge is the appearance of the “corked wine” aroma, caused by the presence of a compound called trichloroanisole or TCA in the stoppers. Due to its high volatility, TCA can migrate from the cork to the wine, adversely affecting its taste.

In this context, the CRAG research team lead by David Caparrós-Ruiz, head of the "Bioengineering of Lignocellulosic Biomass" group, participated in the Cork2Wine project, which is coordinated by the cork company Francisco Oller SA. This project is aimed at identifying the origin of TCA and explore solutions to the “corked wine” aroma problem. Researchers at CRAG analysed cork oak samples from Sardinia and Girona, two regions with different TCA levels in the cork. The comparison of gene activity, achieved through sequencing and comparing RNA molecules, followed by bioinformatics studies, allowed this group to identify a list of phenolic metabolites present in different abundances in the two cork tree populations.

While TCA is present in the cork, microorganisms are known to play a role in its production, which would use the oak’s phenolic compounds identified in this project as precursors to produce TCA. Identifying these precursor compounds is crucial and opens the possibility to build new biotechnological tools aimed at reducing or eliminating TCA in cork.

The Cork2Wine project was a consortium uniting various stakeholders in the cork sector, including companies, wineries, oak farms, a chemical sector company, and research groups. It lasted four years (from 2019 to 2023) and had a budget of almost 5 million euros funded by CDTI Innovation and, in part, with FEDER funds from the European Union, within the framework of the CIEN Strategic Program. The project served as the starting point for this public-private collaboration, which now continues thanks to a new research project awarded within the framework of the Recovery, Transformation, and Resilience Plan with Next Generation funds.

The Cork2Wine project exemplifies how public-private partnerships can translate fundamental research into societal benefits, demonstrating the impact of knowledge generated in the research system on citizens.