Your dinner is printed

At its simplest, the 3D printing of food takes the form of extruding purees through nozzles that consider the viscosity of the original feedstock, and printing it in additive layers onto a platform. The end result is often dried or baked into a biscuit form. The cognoscenti actually call this 2.5D, as the process involves many 2D layers and only the final product is itself a 3D object.

Another approach is to load up a printer with capsules of ingredients, like inkjet printer cartridges. Supply water, oil and heat and the printer can then combine these ingredients into a finished meal. Indeed, food printers could potentially prepare a wide range of meals from a handful of basic ingredients.

No one becomes an astronaut for the quality of the food, which is notoriously bland, largely freeze-dried and lacking in structure or mouth appeal. To date, space missions have been relatively short or are easily resupplied with food items from Earth. With an eye to future morale, and practicality on long-term missions to the Moon and beyond, the space agencies are looking at ways to up their food game.

One series of experiments involved sending living cell cultures of cow muscle cells into space. Reading about the first proof-of-concept experiment bioprinting meat muscle cells on the International Space Station (ISS) in 2019, you could be forgiven for imagining the astronauts wielding steak knives and tucking into a substantial slab of meat. These are the same cells that experimental collaborator Aleph Farms, an Israeli food-tech company, uses to create steaks here on Earth. Didier Toubia, CEO at Aleph Farms, says: “The end product may only have weighed a fraction of a full steak but we were able to demonstrate in a world first that we could assemble 3D tissue from muscle cells and fibroblasts in space.”

Without the assistance of gravity, simple 2.5D additive printing does not work. Enter the OrganAut, a printer about the size of a toaster in the Russian part of the ISS. This is no ordinary printer, as it can print living cells. Its inventor Usef Hesuani, co-founder of Moscow-based 3D Bioprinting Solutions, refers to it as a magnetic levitational ‘bioassembler’. Hesuani’s machine uses strong magnetic fields to shape the growth of living muscle cells. “It works much the same way as we form a snowball on Earth, with the magnetic fields shaping the cell mass as it grows, printing from all sides simultaneously. But the end product will be more of a meatball than a steak,” says Hesuani, laughing. The bioassembler could help maintain the long-term health of astronauts in space outside the world of food, for example, by growing an astronaut’s own cells to replace cartilage or bone lost during long missions.

Back on Earth, Spanish company Novameat eschews meat altogether with a wholly plant-based fake steak composed of seaweed, beetroot juice and peas. The team have patented micro-extrusion technology that allows the laying down of 100-150-micron-diameter microfilaments, which are knitted together to mimic the structure and texture of real meat. The no-meat steak costs $1.50/50g to produce at small scale. Novameat hopes to commission a pilot plant able to produce 50kg of meat per hour in 2021, bringing the unit cost down further.

Dutch start-up Upprinting focuses on waste food items such as misshapen or over-ripe fruit or vegetables, unsuitable for the supermarket delivery chain. Working with top-end restaurants, the firm has also created recipes to explore imaginative uses for leftover bread or rice. The waste food in question is turned into a puree and printed out using a 3D printer, then baked and dehydrated for crunch, texture and longevity. 3D printing of this kind enables shapes, structures and designs that cannot easily be made by hand and can transform ugly unsaleable vegetables into beautiful food.

Currently confined to embellishing the fine-dining plates of posh restaurants with an element of surprise, and a feel-good story for the diner and menu writer, it remains a challenge to see how this approach is truly scalable.

Swiss chocolatier Barry Callebaut may not be a household name, but the company produces chocolate for brands such as Nestle and Cadburys, supplying chocolate goodies around the world. The firm believes that it has cracked the 3D-production scalability problem, allowing it to print thousands of pieces at a time in its Mona Lisa Studio while maintaining the look of hand-made artisanal chocolate.

Whether this is the case is hard to judge, as at the time of writing we have been unable to sample the results. The company uses an automated array of custom printers working together as a ‘printer farm’, having developed the control and automation software in-house.

The food business is beginning to overcome the scalability issues in 3D-printing technology but we are still a long way from the Star Trek food replicator, either here on Earth or in space.