Although it is in its early stages, the idea is to replace harvesting meat from livestock with a process that eliminates the need for animal feed, transport, land use and the methane expelled by animals, which all hurt the environment, he said.

"Keeping animals just to eat them is in fact not so good for the environment," said Roelen. "Animals need to grow, and animals produce many things that you do not eat."

Developed nations are expected to consume an average of 43 kg per capita of poultry, beef, pork and other meats this year, an amount that rises around 2 percent annually, data from the United Nations' Food and Agriculture Organisation shows.

Asked whether people would be repulsed by lab-grown meat, Roelen said he believed there would be enough demand, as much of what people eat today is already extensively processed, from the feed that animals consume to the conditions under which they are raised and the preparation of meat after slaughter.

"I can imagine that some people will have problems with it," he said. "People might think it is artificial. But some people might not realise that some part of the meat they eat is artificial."

Research is also under way in the United States, including one experiment funded by US space agency NASA to see whether meat can be grown for astronauts during long space missions.

But it will take years before meat grown in labs and eventually factories reaches supermarket shelves. And so far, Roelen and his team have managed to grow only thin layers of cells that bear no resemblance to pork chops.

Under the process, researchers first isolate muscle stem cells, which have the ability to grow and multiply into muscle cells. Then they stimulate the cells to develop, give them nutrients and exercise them with electric current to build bulk.

After perfecting that process, scientists will then need to figure out how to layer tissues to add more bulk, since meat grown in petri dishes lacks the blood vessels needed to deliver nutrients through thick muscle fibres.