It looked like a burger. It smelled like a burger. It tasted, well, almost like a burger.

The first lab-grown beef hamburger was cooked and eaten in London on Monday. “We proved it’s possible,” said scientist Mark Post, who created the cultured minced meat in his lab at Maastricht University in the Netherlands. He said his hope is to come up with a new and environmentally friendly way to feed the world.

The scene in Riverside Studios in West London, where the event took place, looked like something you might see on a TV cooking show: There was a fake kitchen counter, a tiny sink, a single burner and, of course, a chef — Richard McGeown, who has worked with such culinary stars as Gordon Ramsay.

The five-ounce burger patty — which cost more than $330,000 to produce and was paid for by Google co-founder Sergey Brin — arrived under a silver dome and was promptly put onto a pan to sizzle with a dab of butter and a splash of sunflower oil. The smells that drifted off toward the audience (a few invited journalists and scientists) were subtle but unmistakably meaty.

Next came the tasting. Besides Post, only two people were allowed to have a bite of the test-tube burger: Josh Schonwald, the American author of “The Taste of Tomorrow,” and Hanni Rützler, an Austrian nutritional scientist. Both said the burger tasted “almost” like a conventional one. No one spat the meat out; no one cringed.

Rützler gave the chef an appreciative nod. “It’s close to meat, but it’s not as juicy,” she said. “I was expecting the texture to be more soft. The surface was surprisingly crunchy.” She added: “I would have said if it was disgusting.” Schonwald said the product tasted like “an animal protein cake.”

Post said that lab-cultured meat can play an important role in the future: Not only could it help feed the planet, but it also could help solve environmental problems stemming from conventional meat production. “At the global level, if all meat would be lab-grown, the greenhouse gas emissions could be reduced by 80 percent, and the water use by 90 percent,” says Hanna Tuomisto of the European Commission Joint Research Centre, who researches potential environmental impacts of lab-grown meat.

As for the nutritional benefits of cultured meat, the jury is still out. But Boston University’s Joan Salge Blake, a registered dietician and the author of “Nutrition & You,” says it has the potential to be healthier than conventional meat. “If they replace the saturated fats with omega-3 fats, that would be great for our health,” she said.

The research

Although the burger was a culmination of a five-year research project, it took Post only three months to grow it, using stem cells harvested from a cow’s shoulder. “That’s faster than [raising] a cow,” he said. Stem cells not only proliferate rapidly but can differentiate into various kinds of cells: muscle cells, bone cells, etc.

The type of stem cells that Post used, called satellite cells, are responsible for muscle regeneration after injury.

Peter Verstrate, a Dutch food technician who worked with Post on the development of the burger and who helped carry the meat to London by train in a cardboard box filled with dry ice, said that people react badly when they hear the words stem cells. But “we don’t eat stem cells, we eat muscles,” he said.

The cells were placed in petri dishes in a nutrient mixture that helps them proliferate. There they grew into thin, 0.02-inch strands of muscle fiber — about 20,000 were used to create the burger presented in London.

Verstrate said that months were spent experimenting on how to make lab-grown strands of muscles into an actual burger. “The first time we baked it, in August last year, it was maybe two, three grams, no more. Mark and I tasted it, and so did a representative of Mr. Brin.”

The most challenging part for Verstrate was getting the color right. “The material was colorless, which was a bit strange. It was more like chicken,” he said. So he added a bit of red beet juice and saffron to color the meat (which were not apparent in the taste, according to Rützler).

Post said that creating the meat was just a first step; he would expect to see cultured meats in supermarkets in 10 to 20 years. At first, according to experts, it might be a luxury item, maybe in the form of such exotic treats as snow leopard burgers or rhino sausages, because it would not be much more difficult to make them than to produce beef or pork.

Among the nutritional questions is the iron content of cultured meat. Post hasn’t tested his burger for this nutrient, and it’s possible that it doesn’t contain the nutritionally valuable iron found in red meats, fish and poultry. That’s something for the Dutch scientist to work on.

The yuck factor

Another challenge is what many call the “yuck” factor. Cultured meat has already been dubbed “Franken-meat” or even “schmeat,” though it may be appealing to some vegetarians and others who oppose using animals for food.

“There is no future in conventional food production. The future is in in-vitro meat,” said Ingrid Newkirk, president and co-founder of People for the Ethical Treatment of Animals, the animal rights group, who popped open some champagne to celebrate Post’s success. “There will be health benefits for human beings because that meat will be clean; it’s not raised on a dirty floor in a feedlot. It’s the beginning of the end of the shameful era of conventional meat production. There couldn’t be a more glorious development.”

Brin said he was motivated to invest in the lab-meat effort for environmental and animal welfare reasons. “When you see how these cows are treated, it’s certainly something I’m not comfortable with,” he said in a video statement played at the tasting. While there was just enough lab meat for one hamburger today, “I’m optimistic we can really scale by leaps and bounds.”

The dream of lab meat harkens back at least 70 years, Schonwald has written. In 2001, NASA funded researchers to grow tiny goldfish nuggets for possible use on future space missions. And in 2003, “bio-artists” from Australia grew small sheep steaks in a lab and served them at a white tablecloth performance art event called “Feast.” Neither project continued.

Brian Vastag contributed to this report.