Scientist Grows $325,000 Burger Using Stem Cells

By Wesley Fenlon

If "fetal calf serum" sounds delicious (or terrible!), this is the lab-grown burger of your dreams.

The Ultimate Burger, declares Modernist Cuisine, is no simple creation. It requires a bun with the perfect--not overpowering!--degree of sweetness, a cheese made with sodium hexametaphosphates, and a meat patty ground in such a way that every strand is aligned to produce an even texture. The meat is then cryofried--dipped in liquid nitrogen and then fried in hot oil--to keep the burger as juicy as possible. It's complicated, but it's still simple (and cheap) compared to a new $325,000 hamburger that will be eaten in London in the near future.

While Modernist Cuisine uses science to find the perfect way to prepare and combine foods, Dr. Mark Post of the Netherlands, creator of this burger, is doing something different--he's trying to prove that we can grow edible meat in a laboratory through the use of stem cells.

Photo credit: Francois Lenoir/Reuters

"In a lab with incubators filled with clear plastic containers holding a pinkish liquid, a technician was tending to the delicate task of growing the tens of billions of cells needed to make the burger, starting with a particular type of cell removed from cow necks obtained at a slaughterhouse," writes The New York Times. "Dr. Post, one of a handful of researchers in the field, has made strides in developing cultured meat through the use of stem cells — precursor cells that can turn into others that are specific to muscle, for example — and techniques adapted from medical research for growing tissues and organs, a field known as tissue engineering...His burger consists of about 20,000 thin strips of cultured muscle tissue. Dr. Post, who has conducted some informal taste tests, said that even without any fat, the tissue 'tastes reasonably good.' For the London event he plans to add only salt and pepper."

Growing the meat for a lab burger isn't cheap--the research has cost $325,000 so far, which means Post's technique poses little threat to the existing meat business. It's a slow process. Post's work uses myosatellite cells, taken from the muscle tissues in a cow's neck. He uses myosatellite cells because they're able to produce new muscle tissue. The cells are placed in a growth medium--in this case, fetal calf serum--and then encouraged to divide and multiply.

Real Meat. Photo credit: Flickr user joshbousel via Creative Commons.

"The cells are then poured onto a small dab of gel in a plastic dish," writes the Times. "The nutrients in the growth medium are greatly reduced, essentially starving the cells, which forces them to differentiate into muscle cells. 'We use the cell’s natural tendency to differentiate,' Dr. Post said. 'We don’t do any magic.'

"Over time the differentiated cells merge to form primitive muscle fibers, called myotubes. 'And then they just start to put on protein,' Dr. Post said, and organize themselves into contractile elements. The key to this self-organization, he said, is that the cells are anchored in place (using a technique that he declined to disclose; earlier in his work he used Velcro). 'We add anchor points so they can attach to something and start to develop tension,' he said. 'That is by far the biggest driver of protein synthesis, and they do that by themselves.'

"The result is a tiny strip of tissue, about half an inch long and only a twenty-fifth of an inch in diameter, that looks something like a short pink rice noodle, Dr. Post said.

"The strips have to be thin because cells need to be close to a supply of nutrients to stay alive. One approach to making thicker tissues — to make a cultured steak rather than a hamburger, for instance — would require developing a network of channels, the equivalent of blood vessels, to carry nutrients to each cell."

This method produces at least one obvious problem: the lab-grown cells will always originate with cells taken from an animal. If cows suddenly went extinct, so would Post's ability to grow more meat. Other researchers are working to find stem cells that could reproduce indefinitely. But Post's research is just a proof of concept, and even if it doesn't lead to a breakthrough in viable cultured meats, it's at least going to set a record for the most expensive hamburger ever made.