winemaking UV light used to soften tannins A method to accelerate the natural ripening process may be available to winemakers once it has gained approval for commercial use. Daniel Whyntie reports. SWISS COMPANY VINOFLUX has developed a method that uses Ultra Violet light to soften tannins and help winemakers combat the issues of overripe fruit characters. It offers winemakers the chance to adjust problematic batches and also delivers another solution for those seeking to make vegan-friendly wines, as the technology does not rely on additives and serves as an alternative to egg whites, fish products and other animal ingredients for fining wine. Winemaker Aldo Bratovic is looking to progress the service towards a commercial scale after initial trials and demonstrations with Australian Wineries. So far Bratovic has run small volume trials of Vinoflux at 80 Australian wineries, treating up to two barrels at a time. There has been no negative feedback. “All the big wineries in Australia and a lot of wineries through the US and a lot of universities have trialled the machine,” Bratovic said. “So far 800 to a 1000 wines have been treated in a trial environment.”
GROUP BONDING The process replicates reactions that would naturally take place over time, as the tannins gradually soften making a wine taste smoother. The process encourages a bond across the exposed hydroxyl groups in short chain tannins, the UV light at specific wave lengths provides a spike of energy which is the catalyst for reaction. UV light can be harmful to wine but Vinoflux utilises specific wavelengths to produce a smoother wine without negatively influencing the fruit or flavour profile. Typically the exposed hydroxyl group would react with salvia and give the mouth feel of tannins, by bonding the groups they are removed from being active. “The more bonding we do, the less groups are able to attach to salvia. This is why they add proteins, ox blood, fish blood, we replace all and every one of those and the process is completely free from any additive,” Bratovic said. Normally additives can be added, causing the hyrdoxical groups to bond
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VINOflux bench top unit with Peristaltic Pump. Used for proof of performance and small scale trials.
It became a lot more useful as a starting point a winemaker could work with. with the protein falling to the bottom of the tank. By avoiding the use of additives no precipitate or waste is created, meaning there is no change in volume.
SOMETHING A LOT MORE USEFUL Bratovic attends one or two of the big trade events each year and first saw the technology at the Simei trade event, in Milan. He heard about Dr. Johann Kreutzinger’s tannin modifying machine and had a couple of wines treated, but the wines only slightly responded. Despite the lacklustre results the pair agreed to meet in Milan, where Kreutzinger happened to have a bottle of very tannic Malbec. “It went from brutally tannic to something much more acceptable. It didn’t become a great wine but it became a lot more useful as a starting point a www.winetitles.com.au
winemaker could work with,” Bratovic said. Interested Bratovic wanted to check the science, so he called his old university lecturer who told him the chemistry had been well understood for decades but he had never seen anything using it. Kreutzinger is a light physicist who studies UV rays and the permeability of cell membranes, he discovered the process during his research. He works in physics not wine but had a Spanish partner with connections in the industry, this partnership brought about the commercialisation of the technique. Vinoflux has been launched in the European market, mostly in Spain and Switzerland where the partners are based. In Australia Vinoflux will be offered as a service to wineries and is currently undergoing trial demonstrations through a portable demonstration model of the device.
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February 2017 – Issue 637