Call me shmeat

The hamburger,assembled from tiny bits of beef muscle tissue grown in a laboratory and to be cooked and eaten at an event in London,perhaps in a few weeks,is meant to show the worldincluding potential sources of research financingthat so-called in vitro meat,or cultured meat,is a reality.

Lets make a proof of concept,and change the discussion from This is never going to work to,Well,we actually showed that it works,but now we need to get funding and work on it, Post said in an interview at Maastricht University.

The idea of creating meat in a laboratoryactual animal tissue,not a substitute made from soybeans or other protein sourceshas been around for decades. The arguments in favour of it are many,covering both animal welfare and environmental issues.

Post,one of a handful of researchers in the field,has made strides in developing cultured meat through the use of stem cells and techniques adapted from medical research for growing tissues and organs,a field known as tissue engineering.

Posts burger consists of about 20,000 thin strips of cultured muscle tissue. 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.

But the meat is produced with materialsincluding fetal calf serum,used as a medium in which to grow the cellsthat eventually would have to be replaced by similar materials of non-animal origin. And the burger was created at phenomenal cost325,000,provided by a donor who so far has remained anonymous.

This is still an early-stage technology, said Neil Stephens,a social scientist at Cardiff University in Wales who has long studied the development of what is also sometimes referred to as shmeat.

There are also questions of safetythough Post and others say cultured meat should be as safe as,or safer than,conventional meat,and might even be made to be healthierand of the consumer appeal of a product that may bear little resemblance to a thick,juicy steak.

Post is well aware of the obstacles. And as with any technology,costs should eventually come down. If it can be done more efficiently,theres no reason why it cant be cheaper, he said. It has to be done using the right materials,introducing recycling,controlling labor through automation.

In his work on cultured meat,Post uses a type of stem cell called a myosatellite cell,which the body itself uses to repair injured muscle tissue. The cells,which are found in a certain part of muscle tissue,are removed from the cow neck and put in containers with the growth medium.

Through much trial and error,the researchers have learned how best to get the cells to grow and divide,doubling repeatedly over about three weeks.

The cells are then poured onto a small dab of gel in a plastic dish. The nutrients in the growth medium are greatly reduced,essentially starving the cells,which forces them to differentiate into muscle cells.

Over time the differentiated cells merge to form primitive muscle fibers,called myotubes. And then they just start to put on protein, Post said,and organise themselves into contractile elements.

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,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 tissuesto make a cultured steak rather than a hamburger,for instancewould require developing a network of channels,the equivalent of blood vessels,to carry nutrients to each cell.

A lot of the technologies in the process we are currently using eventually have to be changed,if not all of them, Post said. Thats not the point of the proof of concept. The point is,we already have sufficient technology to make a product that we could call meat or cultured beef,and we can eat it and we survive.

Henry Fountain