BRENDAN BORRELL / © SCIENTIFIC AMERICAN

Editor's Note: This is the second in a series of six features on the science of food, running daily from March 30 through April 6, 2009.

UTRECHT, the Netherlands—Just down the hall from a frozen vat of pig semen on the über-modern campus of Utrecht University here, Bernard Roelen pulls out a clear, rectangular flask from his precision incubator. The molecular biologist is careful not to leave the door open too long, as slight fluctuations in air temperature, humidity or carbon dioxide are enough to upset the precious piece of pork growing inside. If he succeeds in turning these embryonic stem cells into a slice of sausage, Roelen could make carnivory socially respectable even to the most ardent vegetarian. "There is a point that the Earth is not big enough to have all the animals and the fields to feed all the animals," he says, "You have to think ahead."

According to ecologist David Pimentel of Cornell University's College of Agriculture and Life Sciences, some 12,000 gallons (45,500 liters) of water are needed to produce every pound (0.45 kilogram) of beef, compared with just 60 gallons (225 liters) for a pound of potatoes. Beef requires 27 times more energy to produce than plant protein. The methane burps of 56 billion farm animals (as enumerated by the United Nations Food and Agriculture Organization) are a significant contributor to climate change, and their nutrient-rich manure pollutes waterways. Raised under sterile conditions, lab-grown meat could reduce food-borne illnesses such as Escherichia coli and salmonella. And, for some animal rights activists, meat may no longer be "murder."

Slide Show: Growing Meat inside a Test Tube

In a prescient essay from 1932, Winston Churchill wrote, "Fifty years hence, we shall escape the absurdity of growing a whole chicken in order to eat the breast or wing by growing these parts separately under a suitable medium." Although Roelen has a lot of work ahead of him to fulfill Churchill's prediction, the dream got a boost last April with the first In Vitro Meat Symposium in Norway and with the announcement by the People for the Ethical Treatment of Animals (PETA) of a $1-million prize for a commercially viable in vitro chicken product. When I ask Roelen if he's competing for the PETA prize, he chuckles, "We don't work on chicken."

In any case, with its four-year deadline, the PETA prize is nothing more than a publicity ploy, some skeptics insist. After all, in the past three decades, scientists have only succeeded in deriving embryonic stem cell lines from two animal species: the mouse in 1981 and the human in 1998. "Saying you have meat grown in a lab would already be a big step,” Roelen points out. "Saying you have meat grown from a lab and it's mouse tissue—that's asking too much." Presumably, the same goes for human tissue.

The Dutch In Vitro Meat project is the brainchild of businessman Willem van Eelen, now in his 80s, who nearly starved to death in a Japanese prison camp during World War II and came to believe that in vitromeat could solve world hunger. He later took classes in biology and consulted with researchers and companies over 25 years, culminating in a series of patents on in vitro meat production, which he filed in the late 1990s. In 2005 the Dutch government granted three universities and a Dutch meat processor owned by Smithfield Foods two million euros over four years to develop Eelen's idea.