Post by huLLyPost by SteveHA couple of months ago I had a very rare Ostrich steak in France. That
was quite possibly the best steak of any kind I've ever had.
I've had fantastic Argentinian beef (the best, I think) and great steak
from the Inner Hebrides... hard to call really, but memorable!
Argentinian beef is among the best in the world, though beef from
Kobe-cattle in Japan is possibly better. However is it possible than the
best steak will soon be from a lab? See below (Horrible thought - all those
muscles twitching away in a lab)
http://www.newscientist.com/article.ns?id=dn3208
The World's No.1 Science & Technology News Service
Lab-grown steaks nearing the menu
a.. 09:15 30 December 2002
b.. Holiday feature from New Scientist Print Edition
c.. Wendy Wolfson
Fancy a beefburger, but want to spare the cow? Tissue engineers
experimenting with ways of growing meat in a lab dish could soon provide a
solution.
The aim of the work is to develop food for astronauts on long space
journeys, such as a mission to Mars. But like much other space research,
what happens up there could one day become commonplace down here too - just
look what happened to Velcro.
A NASA-funded team led by Morris Benjaminson, at Touro College in New York
City, has already taken the first steps. The team removed chunks of live
muscle tissue from freshly killed goldfish and raised them in a standard
cell-culture fluid for a week. The tissue grew by as much as 14 per cent,
thanks to partially differentiated "myoblast" cells in the adult muscle
dividing to make more muscle cells, he says.
But growing larger pieces of muscle tissue in the lab will be tricky. The
main problem is ensuring a constant supply of nutrients for the growing cell
mass. In a tissue fed by a blood supply, the capillaries must be no more
than 200 microns apart or else the cells in between become necrotic and the
tissue dies.
Although the Touro team developed techniques for growing white and dark
chicken muscle in the lab, without a blood supply the chicken meat grew for
just two months before it was dead in the dish. Benjaminson is now
submitting another NASA proposal to investigate mechanical or electrical
methods of stimulating blood vessel growth.
Protein spheres
However, you only need to establish a good blood supply if you want to grow
thick slabs of muscle. Vladimir Mironov, director of the Shared Tissue
Engineering Laboratory at the Medical University of South Carolina in
Charleston has other ideas. His team thinks the meat of the future will be a
processed food closer to a sausage or hamburger.
In a detailed project proposal to NASA, he sets out how to grow cells on
protein spheres suspended in growth medium. These could then be harvested
and made into nuggets or patties.
His starting cells will be myoblasts, which normally live at the edges of
muscle fibres and help repair the muscles if they are damaged. They are
better suited than embryonic stem cells, Mironov says, because they are
already part of the way down the road to forming the desired cell type,
rather than being totally undifferentiated.
For the full-length version of this feature, and a dozen more, buy the New
Scientist print edition's holiday special.
Unfortunately, myoblasts do have a big drawback - they cannot survive unless
they can attach themselves to something, and this makes them harder to grow
in a stock. To get around the problem, Mironov plans to mix the cells with
tiny spheres of collagen protein and then keep them in suspension with the
help of a machine called a microgravity bioreactor.
According to Mironov, the simplest meat to grow is seafood because the
myoblasts can be coaxed to divide better, but "chicken is nice", he says.
His dream is that we will eventually be able to grow and cook fresh sausage
overnight at home in special machine, just like a home bread maker.
Food and exercise
Although processed meat is likely to become a reality before more
traditional cuts, researchers have not given up the dream of growing the
perfect filet mignon in the lab. Mironov, for one, has thought of other ways
of getting around the blood supply problem.
He suggests using a bioreactor with a branching network of hundreds of tiny
edible tubes that act like artificial capillaries to convey nutrients to the
growing meat. But to satisfy those who crave the texture and mouthfeel of a
good steak, you need to develop something that mimics the texture of real
meat.
That means generating a complex structure of muscle and connective tissue,
and to do that, the muscle myoblasts need to stretch and contract regularly.
In other words, not only must you feed your steak well, you have to give it
plenty of exercise too.
Herman Vandenburgh of Brown University has proposed a regime for the
physical conditioning of sedentary steaks. Rather than just stimulating them
with electricity or chemicals, Vandeburgh's team has developed chitin beads
that change size when the temperature changes. When attached to the
myoblasts, they force them to stretch and contract.
However, in a cruel setback for astronaut omnivores, NASA has rejected
Mironov's proposal, apparently preferring astronauts to be vegetarians for
the meantime. "People are vegetarians and vegans on Earth and they do quite
well," comments Thomas Dreschel, director of NASA's Fundamental Biology
Outreach Programme. "It is more efficient to grow plants and feed on them.
If astronauts really need essential amino acids, they can eat a pill."
Select cut
But Douglas McFarland, at South Dakota State University in Brookings, who
collaborates with Mironov, disagrees. "Animal protein is a more balanced and
complex protein than a plant protein," he argues. "The body would absorb and
metabolise protein from a pill too rapidly. If you eat protein, then it
takes more time to digest."
Even if NASA is focusing on veggies, maybe Mironov can find funding
elsewhere. "Operations like McDonald's are interested in particular cuts of
meat and efficiency," says Vern Anderson, adjunct professor of ruminant
nutrition at the University of North Dakota. "And you could select for
leanness, or low cholesterol."
Gaining general consumer acceptance of such meat might be possible if it
tasted good. But the reaction of vegetarians and animal rights campaigners
is another matter. If no animal is farmed or slaughtered, and if culturing
cells were more energy efficient than growing meat on the hoof, would that
make it ethically acceptable?
If not, there might still be another way. One researcher recalls a student,
a vegan, who asked if she could just biopsy herself, grow up a steak and eat
it. If you want to eat truly victimless meat, perhaps it is time to put
yourself on the menu.