The SurePure system is a brilliant South African invention that sterilizes liquid by means of UV-lights. By exposing the liquid (albeit wine, milk or fruit juice) to the UV-lights, harmful bacteria and other micro-organisms are destroyed without heating the product, as would be the case with pasteurization and similar processes.

The revolutionary technology has proven a great success in the dairy and fruit juice industries, while large beer producers are doing trials with great expectations.

Theoretically this technology could be extremely useful for wine sterilization as well. However, when the company approached the wine industry, its marketing strategy focused on producing “sulphur-free” wines, with catchy phrases claiming that this is the end of hangovers.

Prominent wineries did trials with varying success, with one of the first winemakers that used the machine (and prefers to remain anonymous), stating that lower sulphur levels could be achieved through SurePure, especially in reds.

“Red wine contains a multitude of natural preservatives like tannins, which can protect it against oxidation. We did fairly successful trials with Merlot, but Sauvignon Blanc was a completely different story.”

Because Sauvignon Blanc doesn’t have the same buffering systems than in the case of red wines, it is a lot more vulnerable. Reductive winemaking has become a norm for Sauvignon Blanc and this is impossible without the use of sulphur. Consequently the South African Wine and Spirits Board has rejected certification for Sauvignon blancs produced using the SurePure technology; claiming that the flavour of the wine is not true to the variety.

And what about claims about the end of hangovers? Didn’t the presence of alcohol occur to them? Although this would obviously have escalated SurePure sales if there was conclusive truth to these claims, but I find this pretty silly.

The SurePure system does however have a role to play in the wine industry, as an option for wine sterilisation and stabilisation – just like cross-flow filters and sulphur have roles to play.

Edo Heyns is a winemaker, turned wine journalist working for WineLand magazine.