Watch out, cork! Sensor developed for cork taste in wine

The molecule responsible for the cork taste in wine can now be clearly detected: With the newly developed sensor, the most common wine defect can already be detected in traces. Other potential applications include the detection of pesticides and explosives. This is shown in a recently published study by researchers at the University of Freiburg with the support of the University of Bordeaux.

If a wine has ’cones’, it is usually the cork that releases the corresponding molecules. These often come from fungicides with which the cork oak has been treated. With the help of a sponge-like, porous supramolecular network, these cone molecules can be ’captured’. As soon as such a substance is present and has settled in the pore of the sensor, it gives an optical signal. This is shown by the fact that the sensor stops fluorescing (glowing) and thus indicates that the wine quality is impaired.

Detection of pesticides or explosives
The study also shows other possible applications. The sensor works for certain pesticides or herbicides, some of which are approved in some countries but banned in Switzerland. For example, traces of these could be detected in fruit and vegetables. The grid-like structure also reacts to explosives and could one day be used to detect explosive substances, e.g. at airports. For the tests, the sensor substance can either be used in solution (in the case of fruit juice or similar) or on a paper test strip. The sensor can be regenerated and is then available again for new measurements.

International collaboration
The scientific work has just been published in the journal ’Inorganic Chemistry’. The study was carried out under the supervision of Katharina M. Fromm and graduate assistant Serhii Vasylevskyi from the Department of Chemistry at the University of Fribourg. Part of the tests were carried out at the University of Bordeaux, France, under the supervision of Dario Bassani from the Institute of Molecular Sciences. The research project was also supported by the Swiss National Science Foundation.