Monday debut for test-tube burger
A slice of history will be served on Monday when the world's first test-tube burger, made from lab-grown meat, is cooked and eaten in London.
The five ounce patty, which cost £250,000 to produce, will be dished up by its creator before an invited audience at a secret location.
Scientist-turned-chef Professor Mark Post produced the burger from 20,000 tiny strips of meat grown from cow stem cells.
He believes it could herald a food revolution with artificial meat products appearing in supermarkets in as little as 10 years.
Prof Post's team at the University of Maastricht in the Netherlands conducted experiments which progressed from mouse meat to pork and finally beef. He said: "What we are going to attempt is important because I hope it will show cultured beef has the answers to major problems that the world faces. Our burger is made from muscle cells taken from a cow. We haven't altered them in any way. For it to succeed it has to look, feel and hopefully taste like the real thing."
Few details of Monday's event have been released but the burger will be fried in a pan and tasted by two volunteers, one of whom may be the anonymous businessman who funded the research.
The raw ingredients sound distinctly unappetising - half-millimetre thick strips of pinkish yellow lab-grown tissue. But Prof Post is confident he can produce a burger that is almost indistinguishable from one made from a slaughtered animal. He points out that livestock farming is becoming unsustainable, with demand for meat rocketing around the world.
A multi-step process is used to turn a dish of stem cells into a burger that can be grilled or fried. First the stem cells are cultivated in a nutrient broth, allowing them to proliferate 30-fold. Next they are combined with an elastic collagen and attached to Velcro "anchor points" in a culture dish. Between the anchor points, the cells self-organise into chunks of muscle. Electrical stimulation is then used to make the muscle strips contract and "bulk up" - the laboratory equivalent of working out in a gym.
Finally the thousands of beef strips are minced up, together with 200 pieces of lab-grown animal fat, and moulded into a patty. Around 20,000 meat strands are needed to make one five ounce burger. Other non-meat ingredients include salt, egg powder, and breadcrumbs. Red beetroot juice and saffron are added to provide authentic beef colouring.
Animal welfare organisation Peta welcomed the move, saying: "Lab-grown meat will provide people who were addicted from childhood to the saturated fat in flesh with the 'methadone' for their habit."