Researchers and professionals of the sector detailed in depth the results obtained through the application of ultrasound in different studies and experiences in wineries.
November 21, 2024. – SIMEI 2024, one of the largest international exhibitions of winemaking equipment and machinery, witnessed last November 14 the presentation “Ultrasound in winemaking, innovative technique in winemaking”. At this meeting, intriguing data was shared on the use of ultrasound to extract compounds such as polyphenolics, polysaccharides, and various aromas in winemaking. This process utilized Ultrawine Perseo, a patented technology by the Spanish company Agrovin, known for its expertise in technological solutions.
The first discusion came from Encarna Gómez, professor at the University of Murcia in the area of food technology, who explained the research carried out on the application of ultrasound in winemaking. Gómez began the presentation by explaining the scientific foundations that justify the use of ultrasound to carry out cavitation in the fluid circulating to the skin cells, in which a large number of compounds linked to the color of wines, their varietal aroma, and mouthfeel are concentrated. The cavitation phenomenon generates bubbles, whose collision causes partial pressures on the plant cells, causing the collapse of the structures, a key aspect in reducing by 50% the maceration times necessary to extract the compounds contained in the grapes.
The professor then detailed the data obtained from the various tests carried out on the Monastrell, Syrah, and Cabernet Sauvignon grape varieties, which showed a notable increase in polyphenol content in the samples subjected to ultrasound, especially in the Syrah and Cabernet Sauvignon varieties, where polyphenol content increased by 26% and tannin content by 32%.
Gómez also delved into the studies carried out on white and rosé wines, with equally satisfactory results, and shared her conclusions about the efficiency of ultrasound as a method of extracting aromatic compounds from grapes when cold, without undesired effects and with the advantages of this type of extraction in avoiding reactions that could degrade the wine’s aromatic compounds during the process.
Federico Casassa, professor of Enology and Wine Sensory Analysis at Cal Poly University, shared the results of ultrasound trials conducted on three vintages of Cabernet Sauvignon reds for pyrazine reduction.
In addition to the data obtained in the chemical analyses, Casassa highlighted the results obtained in the sensory analyses, in which the samples treated with ultrasound showed a greater presence of fruit and, in the unripe fruit, a much lower (often zero) perception of pyrazines. In addition, the mouthfeel of the ultrasound-treated wines was described as rounder, with the efficacy of the method being more notable in those in which more immature fruit had been used.
In his conclusions, Casassa focused on the notable reduction of maceration time (from 14 to 6 days) and the capacity of extraction of aromatic and mouthfeel compounds demonstrated by ultrasound, especially in fruit with less ripening. He also referred to ultrasound as a consolidated technology for the improvement of white, rosé and sparkling wines.
Álvaro Maestro, technical director of Bodega Emilio Moro, shared his experience in the optimization of red wines through ultrasound at the industrial level in the winery.
Maestro pointed out as the main advantage that led him to rent the first equipment: the reduction of up to 50% in maceration times, which also results in a 25% reduction in the need for fermentation tanks.
However, Maestro acknowledged during his speech that he was concerned about the impact that this innovative technique could have on the organoleptic level, so he initially carried out a comparative test with Tempranillo grapes. The result was clear: the color parameters were superior in the ultrasound-treated sample compared to the control made in the traditional way. In addition, after six months of aging, a tasting was carried out with the winery’s internal tasting panel, made up of 4 tasters accredited to the ISO 17000 standard. The result was that there were no organoleptic differences between the control wine and the wine subjected to ultrasound, thus dispelling all doubts and leading the winery to acquire high-capacity equipment with which they have now applied ultrasound to more than 6 million kilos of grapes.
In this way, SIMEI attendees were able to learn first-hand about reliable data on Ultrasound technology.