Magnetised yeast makes sparkling wine faster

The time taken to remove waste yeast from wine can be reduced from weeks to minutes if the yeast itself is magnetised.

The traditional method of producing sparkling wine - Méthode Champenoise - uses yeast to create a secondary fermentation to produce carbon dioxide (CO₂) and the characteristic bubbles associated with sparkling wine.

To remove the spent yeast, traditional methods use a rotate and elevate technique - often done by hand - to allow the yeast to settle in the bottle neck. The neck is then plunged into freezing liquid and the frozen waste yeast plug removed. The whole process can take up to 60 days.

However, a European research team at the University of Ljubljana has found a way to attach magnetic nanoparticles to the surface of yeast. With the use of magnets, waste yeast extraction takes just 15-20 minutes - over 4000 times faster than the traditional method.

The yeast remains unaltered by being magnetised, even after fermentation, and sensory tests suggest the wine’s bouquet, mouthfeel, body, taste, bubble size and overall drinking experience are unaffected by the process.

The Institution of Chemical Engineers (IChemE) chief executive, Dr David Brown, said: “As the global population grows there is pressure on food and drink manufacturers to become more efficient. Saving time and energy is fundamental to this if we are to maintain adequate food supply.

“Quality of life is important too and wine is enjoyed by millions of people. Although many wine connoisseurs will stay loyal to traditional manufacturing methods, the inventiveness of chemical and biochemical engineers demonstrates that even wine production ... can be made more efficient with clever nanotechnology combined with simple magnets.”

The role of chemical engineers in the health, water, food and energy sectors is explored in IChemE’s latest technical strategy, Chemical Engineering Matters.