Scientists 3D print Wagyu beef-like meat

With increasingly urgent warnings that the world must cut carbon emissions immediately and drastically if it is to meet Paris Agreement targets, there is growing interest in meat alternatives which are not associated with heavy carbon emissions. Of common meats, beef is the biggest offender by far, generating 60kg of greenhouse gas emissions per kg of meat produced.

Although the way beef is produced today is considered environmentally unsustainable, there are no entirely satisfactory cultured meat alternatives. Available synthetic beef – and other synthetic mammalian meat – consists of poorly organised muscle fibre cells without the structure of real beef steak.

In an effort to construct synthetic meat that more closely mimics the real thing, Osaka University researchers used stem cells from Wagyu cows to 3D print a meat alternative with its muscle, fat, and blood vessels arranged to closely resemble wagyu steak. Wagyu steak is distinctive for its high intramuscular fat content, known as marbling or sashi. The beef comes from four breeds of cattle, which are fed for 600 days (twice as long as other breeds) in a relaxed environment, resulting in fatty meat which cooks into a rich and juicy steak with a unique taste and texture.

“Using the histological structure of Wagyu beef as a blueprint, we have developed a 3D printing method that can produce tailor-made complex structures, like muscle fibres, fat and blood vessels,” explained Dr Dong-hee Kang.

The researchers began with two types of “multipotent” Wagyu stem cells: bovine satellite cells and adipose-derived stem cells. Under certain laboratory conditions, these cells can be made to differentiate into every type of cell necessary to produce the synthetic meat.

They bio-printed individual fibres which incorporated muscle, fat or blood vessels, fabricated from these cells. The fibres were then arranged to reproduce the structure of Wagyu meat, with the fibres aligned in a tendon-like gel. In their demonstration, the Osaka University researchers used 72 fibres (42 muscles, 28 fat tissues and two blood vessels) and produced a piece of synthetic meat with diameter 5mm and length 10mm.

Finally, it was sliced perpendicularly to reveal the marbled structure characteristic of Wagyu beef.

The process promises to make it possible to create and customise complex meat tissue structures.

“By improving this technology, it will be possible to not only reproduce complex meat structures, such as the beautiful sashi of Wagyu beef, but to also make subtle adjustments to the fat and muscle components,” said Michiya Matsusaki, senior author of the Nature Communications study. That is, customers would be able to order cultured meat with their desired amount of fat, based on taste and health considerations.