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.
By experimenting with water activated with cold plasma — a lower-temperature version of the typically superheated matter — the researchers were able to help pea protein hold its shape better after 3D food printing.
The findings from the study — one of the first to explore the improvement in 3D printability by cold plasma technology and the feasibility of applying pea protein as a major component in 3D food printing — strengthen the potential for using the low-cost, highly nutritional product in several food-related ways, says M.S. Roopesh, an associate professor in the Faculty of Agricultural, Life & Environmental Sciences and one of the authors on the paper.
“By improving the gelation and 3D printability, pea protein can be used in several applications, including expanding the selection and boosting the structural properties of plant-based meat and cheese.”
Development of 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 including fava beans, adds Roopesh, who conducts his work through the U of A’s Food Safety and Sustainability Engineering Research lab.
The 3D printing process creates foods with complex shapes, flavours and textures for everything from home and restaurant meals to personalized diet plans.
Readily available from legume crops grown on the Canadian prairies, pea protein, which is hypoallergenic, is already used as a main ingredient in bread, cereals, plant-based dairy products and meat substitutes.
And while it’s a good candidate for food and ingredient applications and emulsion preparation, it’s difficult to use for 3D printing because it doesn’t hold its shape and structure after being squeezed out of the printer nozzle, he notes.
In their 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. The printed gels were then observed for how well they held together.
Compared with pea protein mixed just with distilled water, the PAMB-treated gels had better structure retention and resistance to deformation, and were more stable during storage after printing, the experiments showed.
“The improvements were possibly due to some structural changes in proteins” brought on by the PAMB water, notes Roopesh, one of the researchers exploring those various mechanisms.
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.
And though further research is needed to understand those influencing factors, “it’s also promising work that strengthens what we know about the wider applications of cold plasma,” Roopesh says.
The study is the latest to support initial experiments with cold plasma treatment of pea proteins to make gels that were started in collaboration with ALES professor Lingyun Chen and developed by former PhD student Sitian Zhang. The patent pending work is open for licensing.
Improvement in 3D printability of the gels was further refined by former student Sreelakshmi Menon, who conducted the work to earn a master’s degree in food science and bioresource technology. The study was part of a collaborative project involving Roopesh and former colleague John Wolodko, funded by Alberta Innovates.
The foundational research using cold plasma paves the way for more extensive work to create a wider range of high-quality, 3D printed protein sources and other biomaterials, Roopesh adds.
“Combining novel technologies like cold plasma and 3D printing for the production of better plant protein and biomaterial gels, we have the potential to really add value for crop producers and the food industry.”
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.