Who did not dream Coming home after a long day and pressing just a few buttons to get a hot, home-cooked 3D-printed meal, courtesy of someone’s digital personal chef? This can make microwaves and conventional frozen TV dinners obsolete. Engineers at Columbia University are trying to make that idea a reality, and they have now figured out how to cook 3D-printed and authentic chicken layers at the same time, according to a recent study published in the NPJ Science of Food Journal. Of course, it’s not the equivalent of a Star Trek replicator, which can synthesize whole foods on demand, but it’s a start.
Kothar Hub Lipson runs the Creative Machine Lab at Columbia University, where the research was conducted. His team first introduced 3D printing of foodstuffs in 2007, using the Fab @ Home personalized fabrication system to create multi-material edible 3D objects with cab frosting, chocolate, processed cheese and peanut butter. However, commercial equipment capable of simultaneously printing and cooking food layers does not yet exist. There has been some research on how to cook food using lasers, and Lipson’s team thought it could be a promising way to explore further.
“We noticed that while printers can produce material for millimeter accuracy, there is no method of heating with the same degree of resolution,” said co-author Jonathan Blutinger. “Cooking is essential for the development of nutrition, taste and texture in many foods, and we wonder if we can create a method with lasers to properly control these properties.” They used a blue diode laser (5-10 watts) as the primary heating source but tested with near and mid-infrared lasers for comparison, as well as a conventional toaster oven.
Scientists bought raw chicken breast from a local convenience store and then refined it in a food processor to get a smooth, uniform consistency. They remove any tendons and do not cool the samples before re-packaging them in a 3D-printing syringe barrel. Cooking equipment uses a high-powered diode laser, a set of mirror galvanometers (electric current detectors that isolate light rays), custom 3D printing, laser shielding and a removable tray on which 3D-printed cooking is done.
“During the initial laser cooking, our laser diode was mounted on a 3D-printed fixture, but with the progress of testing, we were transformed into a setup where the laser was mounted vertically on the head of the extrusion mechanism,” the author writes. “This setup allows us to print and cook ingredients on the same machine.” They also tested how to cook printed chicken after sealing it in plastic packaging.
The results? Laser-cooked chicken retains twice as much moisture as conventional cooked chicken and it shrinks in half while maintaining the same flavor. But different types of lasers have given different results. The blue laser proved ideal for cooking chicken internally at the bottom of the surface, while infrared lasers were good at browning and broiling at the surface level. In the case of chickens in plastic packaging, the blue laser achieved slightly browning, but was more efficient in turning chickens brown through near-infrared laser packaging. The team was able to brown the surface of the packaged chicken in a pattern similar to the grill mark.