Ultrasonic Cleaning Eliminates 100% of Barrel Bacteria, Transforming Wine Quality at French Estates

In the Médoc region of France, Château Charmail has adopted a new approach to barrel maintenance that is drawing attention in the wine industry. For the past five years, the estate has used ultrasonic technology to regenerate its oak barrels, working with the French company Dyogéna. This method aims to address several challenges faced by winemakers: ensuring the cleanliness and health of barrels, maintaining wine quality, and controlling costs.

Traditionally, wineries have relied on methods such as high-pressure hot water rinsing, steam cleaning, chemical disinfectants, or even sandblasting and manual brushing to clean barrels. Each technique comes with its own set of advantages and drawbacks. Some can be aggressive on the wood, while others may not fully eliminate bacteria or old yeast that can spoil wine.

Ultrasonic regeneration uses sound waves to clean and sanitize the inside of wooden barrels. According to studies by the Institute of Vine and Wine Sciences (ISVV) and more than a decade of practical use in regions like Champagne, Burgundy, and the Rhône Valley, this technology is effective at removing residue and extending barrel life. The process takes only a few minutes per barrel and does not require harsh chemicals. It also reduces water and energy consumption compared to traditional methods.

Dyogéna, based in Blanquefort near Bordeaux, is currently the only company offering this specialized service for wooden barrels. The company operates mobile units that travel to wineries across France and other European countries such as Spain, Portugal, and Germany. Soon, Dyogéna plans to install a fixed machine at a client’s site with a large number of barrels.

Sébastien Pineau, Technical Director at Château Charmail, explained why the estate chose this method. He said that their main goal was to find a cleaning system that would guarantee sanitary safety without damaging the wood. After testing ultrasonic cleaning on a selection of barrels from different coopers—comparing it with their usual hot water method—they noticed clear differences in the resulting wines.

Pineau described how wines aged in ultrasonically cleaned barrels had more volume on the palate and less dryness from tannins. The wines also showed more aromatic complexity and roundness. In contrast, wines from barrels cleaned with high-pressure water tended to be drier.

Château Charmail rents its 500-liter barrels for aging wine over one year. After each cycle, they use ultrasonic cleaning before reusing the barrels for up to three years. Pineau noted that this process leaves the barrels hygienically similar to new ones—free from scale buildup, bacteria, or unwanted yeast.

The adoption of ultrasonic barrel regeneration reflects broader trends in winemaking toward sustainability and precision. By reducing water and energy use while improving wine quality and barrel longevity, estates like Château Charmail are setting new standards for cellar management. The technology’s ability to eliminate 100% of wild yeasts and bacteria without chemicals is especially important for producers seeking consistency and purity in their wines.

As more wineries look for ways to balance tradition with innovation, ultrasonic cleaning may become an increasingly common sight in cellars across Europe and beyond. For now, Château Charmail’s experience offers a glimpse into how science is shaping the future of winemaking in one of France’s most storied regions.