The University of Washington’s Alshakim Nelson has reportedly discovered a novel way to ferment yeast with a 3D printer.
The process has been used exclusively so far to create ethanol, but Dr Alshakim Nelson and his team will soon attempt to expand into other substances such as proteins or even drugs.
According to the Economist, Dr Nelson’s team “have developed a bioreactor that not only keeps bugs alive and active for months at a time, but can also be made in minutes, using low-cost chemicals and a 3D printer.”
3D printing drinks
The process is all enabled by a 3D printed hydrogel lattice. Not only has Nelson’s team developed the hydrogel material themselves, with 70% water and 30% polymer infused yeast, they have also created the unique 3D printer to extrude it.
With a consistency akin to peanut butter, the material has been developed especially with extrusion in mind. Once 3D printing the material in thin lattice layers to create a cube, the hydrogel is then cured with ultraviolet light to solidify its shape. The cubes produced are currently 1 cm in each dimension.
These 3D printed cubes are then placed in a solution of glucose in order to ferment just as they would in a brewery setting. The impressive results of this have led Nelson to ponder,
Can we take our yeast, embed it in hydrogel, print it as a cube, put it in fruit juice and convert it to alcohol?
Elsewhere in the 3D printed drinks industry, an Austrian group has been awarded a prize for its use of a KUKA robotic arm to 3D print drinks. The ‘PRINT A DRINK’ process injects microliters of edible liquid in what it claims is the “world`s first 3D printing process for drinks and other liquid foods.” Perhaps in the future such a technique could be complimented by Nelson’s 3D printed yeast.
Nelson and his team were expecting the cube to ferment using the glucose, however they were definitely not expecting the cube to keep on giving. Reportedly, the bioreactors have been producing ethanol for four months straight so far and show no signs of stopping.
Dr Nelson and his team are unsure what causes this continuous fermentation phenomenon but explains the confinement of the hydrogel lattice is simultaneously stopping the yeast cells from reproducing or ageing.
This revelation has huge significance as the Economist explains,
If it could be industrialised, it would pave the way for continuous fermentation to replace today’s batch-processing approach, with all the advantages such continuity of production would bring.
His team will now focus on expanding the size of the yeast infused hydrogel cubes and will also look towards the creation of proteins. Looking further into the future, the method could also have positive ramifications on drug production.
3D printing hydrogel is becoming a beneficial practice for creating a number of structures from knee implants to fish-catching soft robots but hasn’t until now been used to get people drunk. It’ll be interesting to see how Nelson’s process develops and if the yeast ever stops fermenting.
Featured image shows yeast cells. Image via BBC.