IN-VITRO MEAT

By Nicola Jones

Mark Post has never been tempted to taste the 'fake' pork that he grows in his lab. As far as he knows, the only person who has swallowed a strip of the pale, limp muscle tissue is a Russian TV journalist who visited the lab this year to film its work. "He just took it with tweezers out of the culture dish and stuffed it in his mouth before I could say anything," saysPost. "He said it was chewy and tasteless."

Post, who works at the Eindhoven University of Technology in the Netherlands, is at the leading edge of efforts to make in vitro meat by growing animal muscle cells in a dish. His ultimate goal is to help rid the world of the wasteful production of farm animals for food by helping to develop life-like steaks. In the near term, he hopes to make a single palatable sausage of ground pork, showcased next to the living pig that donated its starter cells — if he can secure funds for his research.

Post started out as a tissue engineer interested in turning stem cells into human muscle for use in reconstructive surgery, but switched to meat a few years ago. "I realized this could have much greater impact than any of the medical work I'd been doing over 20 years — in terms of environmental benefits, health benefits, benefits against world starvation," he says. Largely because of the inefficiency of growing crops to feed livestock, a vegetarian diet requires only 35% as much water and 40% as much energy as that of a meat-eater¹. 

Future 'in-vitrotarians' should be able to claim similar savings. The prospect of an alternative to slaughtering animals led People for the Ethical Treatment of Animals based in Norfolk, Virginia, to announce two years ago a US$1-million prize for the first company to bring synthetic chicken meat to stores in at least six US states by 2016. In the Netherlands, where the vast majority of work has been done so far, a consortium of researchers convinced the government to grant them £2 million (US$2.6 million) between 2005 and 2009 for developing in vitro meat.

Such incentives have helped to solve some of the basic challenges, applying human tissue-engineering techniques to isolate adult stem cells from muscle, amplify them in culture and fuse them into centimeter long strips. But far more money and momentum will be needed to make in vitro meat efficient to produce, cheap and supermarket-friendly. Post estimates that creating his single sausage will require another year of research and at least $250,000. So what still needs to be done?

Choose the right stock

The first question for researchers is which cells to start with. Embryonic stem cells would provide an immortal (and therefore cheap) stock from which to grow endless supplies of meat.

 However, attempts to produce embryonic stem cells from farm animals have not been successful. Most work so far has been on myosatellite cells, the adult stem cells that are responsible for muscle growth and repair. These can be obtained by a relatively harmless muscle biopsy from a pig, cow, sheep, chicken or turkey; the desired cells are then extracted using enzymes or pi-petting  and multiplied in culture.