Definition: Solarisation

The principle of solarisation, which reflects the sun's rays onto the vine leaves, is achieved thanks to this reflective fabric placed under the vines. Research (University of Montpellier) began in 1991, initially with a thermal purpose, but it appears that the light effect prevails. Once this effect had been demonstrated, the challenge was to find a suitable reflective film that was effective, sufficiently strong and did not interfere with the winegrower's work. Starting with a simple aluminium film, five years of research enabled a company in Isère (MDB Texinov) to develop Vitexsol (€1.3 per linear metre, the width is not specified), in which tiny strips of aluminium are attached to a synthetic thread mesh, causing the rays to be reflected in all directions. This "fabric", which was initially green, was then produced in a "red" version, which appears to be more effective in terms of the aromatic potential of the grapes. Tests in France, Germany and Spain have shown that the use of Vitexsol leads to a 25% increase in the light energy received by the plant and improves its health. Tests carried out in certain Bordeaux châteaux showed that wine produced from "solarised" grapes had more colour and that the typical characteristics of the grape varieties were more pronounced. The INAO has banned the use of Vitexsol in AOCs, as it alters the characteristics of the appellation's terroir and removes the link between the wine and its geographical environment.