Using plasma, the stuff of the universe, University of Alberta researchers have improved the 3D printability of a valuable plant protein for use in food here on Earth. 

3D food printing creates customized, edible foods by layering ingredients through a specialized printer. The process, which is still being developed and adopted, can be used to create foods with complex shapes, flavours and textures for everything from home and restaurant meals to personalized diet plans.

By experimenting with water that has been activated with cold plasma—essentially, a lower-temperature version of the typically superheated matter—researchers were able to get pea protein to hold its shape better after printing. Pea protein is a main ingredient in bread, cereals, plant-based dairy products and meat substitutes. But it has been difficult to use in 3D printing because it doesn’t hold its shape and structure after being squeezed out of the printer nozzle.

The findings from a recent study published in Food Bioscience strengthen the potential to use pea protein in several food-related ways, says M.S. Roopesh, an author on the paper and associate professor in the University of Alberta’s Faculty of Agricultural, Life & Environmental Sciences. The study was among the first to explore the use of cold plasma technology to improve 3D printability and the feasibility of using pea protein as a major component in 3D-printed food.

The study found that pea protein has the potential to boost the structural properties of plant-based meats and cheeses and expand their variety.

Better 3D-printed structures can also improve the texture of food products from other plant-based sources, such as proteins and starch from grains, algae and pulses, adds Roopesh, who conducts his work through the university’s Food Safety and Sustainability Engineering Research lab.

To conduct the study, the researchers mixed pea protein with various formulations of plasma-activated microbubble water, called PAMB, to produce a substance that was stirred, heated, cooled and put through a 3D food printer. Then they observed the printed gels to see how well they held together. Compared with pea protein mixed with distilled water only, the PAMB-treated gels were better at retaining their structure and resisting deformation, and were more stable during storage after printing.

The improvements were possibly due to some structural changes in the proteins brought on by the PAMB water, notes Roopesh.

The findings build knowledge about the characteristics of the air and argon gas mixes in the PAMB water—and the optimum heating and cooling temperatures used to prepare the gels—that created the best 3D printability, he adds. 

The study is the latest to support initial experiments—started in collaboration with Faculty of Agricultural, Life & Environmental Sciences professor Lingyun Chen and developed by former PhD student Sitian Zhang—involving cold plasma treatment of pea proteins to make gels. The patent- pending work is open for licensing. 

The study was part of a collaborative project involving Roopesh and a former colleague, John Wolodko. Sreelakshmi Menon, a former student, contributed to the improvement in 3D printability of the gels.

The foundational research paves the way for more extensive work to create a wider range of high-quality,3D printed protein sources and other biomaterials.

“By combining novel technologies like cold plasma and 3D printing to produce better plant protein and biomaterial gels, we have the potential to really add value for crop producers and the food industry,” says Roopesh.

The study was funded by the Natural Sciences and Engineering Research Council of Canada through its Discovery Grants and Collaborative Research and Training Experience programs and by Alberta Innovates. 

This article was adapted and republished with permission from the University of Alberta.