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THE MICROSCOPE • Vol 59:2, pp 73-81 (2011)

Cultured Meat: Food for the Future

C R I T I C A L C R I T I C A L C R I T I C A L C R I T I C A L C R I T I C A L FOCUSFOCUSFOCUSFOCUSFOCUSBrian J. Ford

From living animal cells wecan mass-produce food for anexpanding population thatis facing global shortages.

Journalists say the funniestthings. “You were quoted as say-

ing that people could create revo-lutionary food for the future out ofliving cells,” said one recently. “Isit feasible?” Of course it is. Whatdid he think he’d eaten for break-fast? It is curious how easily weoverlook the fact that our food is largely composed ofcells, either living or dead. Yet, this simple propositionhelps make sense of our diet, assists us when we workon how to handle food safely—and offers radical newideas on how we could mass-produce food for themushrooming human populations of the near future.

As a student, I was dissatisfied with the way thatfood, safety, microbiology and hygiene seemed to beconfused in the minds of the teachers. That was why Iwrote the textbook Microbiology and Food when I wasstill in my twenties, and it became widely consulted.Recently, I was accosted after giving a lecture by a NewZealand professor who said he still used the book regu-larly to illustrate his lectures. Although I was glad tohear that, the book is woefully out of date, and I hopehis students are aware of that. Microbiology and Foodlooked at these interrelated subjects from the singleviewpoint of the living cell: the cell as feeder, cells asfood, as the maker of food and as the agent of spolia-tion. The book did provide a pleasingly coherent basisfrom which to discuss these subjects. Lurking behindthe thesis was the idea that food can usefully be con-sidered from the standpoint of the living cell, and that

remains a crucial concept.I returned to the topic in Mi-

crobe Power, Tomorrow’s Revolution.In this book, I looked at the pro-duction of cell cultures on a largescale as food for a hungry world.At the time, Fusarium venenatum, afungus found in a wheat field, was

showing promise as a candidate for the mass produc-tion of proteinaceous foodstuffs, and I envisaged facto-ries in the Arctic producing these novel foods on anunprecedented scale. My proposal to construct thesefactories in the icy wastes of the far north took intoaccount the fermentation process that would generatelarge amounts of heat. Rather than harness this en-ergy (which would be the modern answer), I proposedthat the low Arctic temperatures would offer the per-fect heat sink for the process. At the time, the resultantwarming seemed inconceivably small. In an era whenexplorers find their way to the North Pole blocked bydeep lakes of liquid water, when the Northwest Pas-sage is being opened for traffic, and when submarinescan surface at the melted pole for a game of football onthe surrounding ice, the idea of Arctic warming doesnot seem so inconsequential. Thank heavens nobodytook up my proposal and developed it in practice.

The subject is current again because of pressureson our food supply. Humans can no longer afford toeat meat in the future as we have done in the past.Livestock production imposes a vast burden on globalresources—a burden that the expanding world popu-

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lation can no longer sustain. A 1981 article in Newsweek,“The Browning of America,” pithily said, “the waterthat goes into a 1,000 pound steer would float a de-stroyer.” Estimates now suggest that it takes about2,500 gallons of water to make a pound of beef, thoughit depends on whom you ask for the estimate. TheAmerican meat industry puts the demands far lower,at less than 450 gallons, but even that is an unsustain-able amount of water.

Imagine if we were able to culture such food infactories. We might be able to manufacture virtuallylimitless supplies at a greatly reduced cost and asmaller environmental impact. There is an upsurge ofinterest in the possibilities of meat produced from cul-tured cells in vitro. America has shown little interest,but there is active research elsewhere, particularly inthe Netherlands. But can we change attitudes so thatscientists start to see food from the viewpoint of theliving cell? When a successful product emerges, whatshould we call it? How does it fit into a broad socialcontext? Can it work? Does it matter? Will it solve our

current demand for food? What will be the environ-mental consequences? Would people accept it, and howdiverse are public attitudes toward the consumptionof meat?

Culturing meat is certainly becoming fashionable,but it is not a new concept. In 1932, Winston Churchillwrote: “Fifty years hence we shall escape the absur-dity of growing a whole chicken in order to eat thebreast or wing by growing these parts separately un-der a suitable medium.” This idea seems very far-sighted, and it has often been quoted. There are morethan 3,500 websites that cite Churchill’s words. Yetthe idea was not his own. Two years earlier, the writerand conservative politician Frederick Edwin Smith,First Earl of Birkenhead, and a friend of Churchill’s,had written: “It will no longer be necessary to go to theextravagant length of rearing a bullock in order to eatits steak. From one ‘parent’ steak of choice tendernessit will be possible to grow as large and as juicy a steakas can be desired.” Very few websites include his ideas;about 20 sites quote the second sentence and only four

In 1930, Frederick Edwin Smith (left), an eminent British writer and politician, predicted the era of cultured meat, saying it would be possiblein a culture “to grow a large and . . . juicy steak” instead of slaughtering a steer. Winston Churchill (right), who was a close friend of Smith’s,appropriated his ideas in 1932 by writing about how one could grow chicken breasts instead of farming chickens. Churchill’s words arewidely quoted, whereas Smith’s have been largely forgotten.

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currently publish the whole quote. Yet this was animportant breakthrough in thought, and it dates backmore than 80 years. Since then, little has happened.

DEPLETING RESOURCES

Although we are being urged to cut down on burn-ing fuels for transportation, it is important to realizethat rearing livestock for meat production pumps moregreenhouse gases into the atmosphere than the entiretransportation network of the world. The productionof meat consumes 8% of all freshwater and involves30% of the ice-free land surface of the earth. This is thesame as the amount of land surface unsuitable for graz-ing or cultivation, and much the same as the area cov-ered by forests.

The West is greedy. American figures show thatthe amount of food and grains that supply the averageworld inhabitant is 1,353 pounds per capita annually. Itis far less in China, 1,028 pounds, but in the UnitedStates the amount of grain used to raise beef raises thepersonal annual consumption to 3,265 pounds, nearlythree times as much as the average across the world.More species of wildlife have been driven to extinctionby raising livestock than through any other cause. InCentral America, more than a quarter of all the rainforests have been converted to cattle rearing since 1960.In Panama and Costa Rica, 70% of the native tropicalrain forest has been burned and converted for rearingcattle. Roughly 40% of the land area of Brazil has beencleared for raising beef.

Pressures on resources have led to a sudden in-crease in the productivity of animal farming. For alltheir reputation in the Western world as “animal lov-ers,” the British still produce eggs in battery farmswhere several hens can be confined in a cage measuringno more than 18 x 20 inches (approximately the samesize as a microwave oven). With a wingspan of only 30inches, we can see that severe constraints are put uponthese birds. A hen in its wild state lays about 20 eggseach year, but selective breeding has given us breedsthat lay 300 each year, approaching one every day.

In the U.S., chemical growth promoters are widelyused to boost the amount of meat obtained from eachanimal. Less than a decade ago, a range of antibioticswas routinely fed to European farm animals to increasethe amount of meat they produced. Questions havearisen over the long-term effects on human health, andmany countries around the world simply ignore newregulations designed to protect the consumer. Meatfarming is globally important, and we need to face therealities as we lurch unsteadily into the future. Beef-

steak has long been popular in the U.S., more so than inalmost any other country (except Argentina). InAmerica, cattle are iconic, virtually a symbol of goodeating and a hallmark of virility. In 1999, cattle becamea major art form when Chicago held the inaugural“CowParade” street exhibit in which life-size fiberglassbovines were decorated by noted artists. Some wereemblazoned with pastoral scenes and abstract designs,while others were adorned with bizarre clothing, flow-ers and flags. At the exhibit’s staging in New York Citythe following year, a sculpture by filmmaker DavidLynch portrayed a cow in the process of being ren-dered for human food. Its head was missing, and a largebloody gash had opened the animal from the backboneto show the viscera. This sculpture was entitled “EatMy Fear.” Some spectators were so upset at the imageof a cow being butchered for food that Lynch’s sculp-ture was removed from the exhibit. The practical re-alities of beef production are something people tend tofind unacceptable, even in America. The bloody natureof the butchering process is something we choose toignore, even though that scrumptious steak on yourplate has come directly from the slaughterhouse.

IMMINENT FAMINE?

Alternatives to meat avoid any unsavory killing,of course, so what about producing cultures of cells asfood? In London in the 1820s, Thomas Malthus hadpredicted that agriculture could not keep pace withpopulation growth, and the view had remained cur-rent. By the 1950s, it was widely believed that theworld was shortly heading for a massive famine, andenterprising food companies began to look at novelproteins and investigated cell cultures as a possibleanswer to a global food shortage. Fungus colonies wereknown to be potentially nutritious, and cultures ofpossible fungal products were soon under way. In 1967,scientists at the British food manufacturer Rank HovisMcDougall (RHM) isolated an ascomycete mold, namedFusarium venenatum, from soil in a wheat field, whichproved to be easy to culture in bulk. In 1980, RHMwere authorized to produce foods made from Fusariumfor public consumption. The product is marketed un-der the name of Quorn, and it is now invading theAmerican market.

In the event, the predicted global food shortagedidn’t happen at the time. For decades, right up to thenew millennium, scientific agriculture continued tokeep pace with demand. When there have been tragicepisodes of mass starvation, they were not due to ashortage of food—only to a shortage of political will-

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ingness to distribute it. The well-known famine ofEthiopia in 1984 was caused by political intransigence.The Ethiopian government was exporting grain anddevoting almost half of the gross national product tomilitary expenditure at the time, because they werefighting a breakaway movement in Eritrea. Trucksbearing food aid were not permitted to enter the rebel-lious territories where the population was starving.The 2011 famine in Somalia was similarly exacerbatedby extremists who refused to allow relief trucks to en-ter the territories they controlled.

There has been enough food for everyone for de-cades. In Europe, we even saw “wine lakes” and “but-ter mountains” as surplus production was stockpiled.For a television program, I waded through a hugewarehouse containing thousands of tons of surplusgrain. Huge amounts of food were being destroyed.The demand for a substitute food like Quorn had beenovertaken by events, and the business model becameobsolete. Instead, the makers decided to market it as ahealth food. There are plenty of precedents. Tempeh is atraditional meat substitute produced in a time-hon-ored fashion in Indonesia by fermenting cooked soy-beans with the common pin-mold Rhizopus. The fun-gal threads bind the bean protein together into a tastymass that contains all the essential amino acids, whichmakes it an excellent vegan food. A similar traditionalfood is the bean curd tofu, which looks like a soft cheese.It originated in China as doufo and is made in Japan by

coagulating curds of protein from soy milk. Tofu is in-creasingly popular in the West, because it is rich innutrients and can lower blood levels of low-densitylipids—popularly known as “bad cholesterol”—by30%.

People like fungus proteins. In a newspaper inter-view that was widely published around the world in2005, I argued: “The widespread acceptance of meatsubstitutes such as Quorn, a cultured fungus, showsthat the time for cultured tissue is near.” If this couldbe achieved, we would be able to mass produce beef-steak without slaughtering another living creature.The objection is sometimes termed the “yuck” factor.The term was put to me by a young journalist fromthe science magazine Focus, who recently interviewedme on the topic. I don’t think it matters. Quorn is basedon highly refined technology and offers the consumera food that nobody can obtain in the natural course ofevents. It is entirely unnatural, and high in potentialyuck factor, yet people are buying it in increasinglylarge amounts.

BACTERIA ARE BASIC

So, could it be done? The first requirement is a foodsource for the growing meat cells, and cyanobacteriaare a clear candidate. Cyanobacteria are fast-growingsimple photosynthetic bacteria with a dry weight pro-tein content of up to 70%, and they can easily be grownin mass culture. So here we have a basic feedstock thatcould be used to make a growth medium. We can cul-ture animal cells and have been able to do so for acentury. In 1885, the pioneering Germany embryolo-gist Wilhelm Roux maintained living tissues from themedullary plate of an embryonic chick in saline solu-tion for several days. Ross Granville Harrison was ananatomist at Yale University who immersed himselfin in vitro research as a way to escape lecturing (whichhe abhorred), and a century ago he launched the newscience of tissue culture. He produced a torrent of pa-pers—up to six in one year—on transplanting limbsin embryos, and in 1912, published “The Cultivationof Tissues in Extraneous Media” in Anatomical Record.This is interesting in itself—the practice of tissue cul-ture predates Smith’s prediction by 18 years.

I was first involved with the subject in 1960, whenI worked on tissue culture in my year with the MedicalResearch Council in the UK before going to university.I had speculated on the mass production of culturedcells as human food in my book Microbe Power, publishedin 1976. In 2000, my book The Future of Food was pub-lished. Although cultured meat was not a topic I ad-

“Eat My Fear,” a sculpture by David Lynch, was removed fromNew York’s “CowParade” in 2000 after spectators became upset atthe portrayal of a cow butchered for food. The practical realities ofbeef production are something people tend to find unacceptable.

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dressed in that book, I was asked to discuss culturedmeat in several programs until 2007, when I was in-vited to join New Harvest, a nonprofit organization, topromote advances in meat substitutes, including cul-tured meat. Two years later, I was invited to contributea chapter for a book in a series entitled Death and Anti-Death. The request came from Dr. Charles Tandy of RiaUniversity Press in Palo Alto, Calif., who formally in-vited me to contribute a chapter on cultured meat. Itappeared in December 2009, and was the first-ever chap-ter to be published on the subject. Many of the ideas inthis column were first published in that book.

Research had been interminably slow to start un-til NASA awarded a grant in 1999 to biologists MorrisBenjaminson and Jim Gilchriest at Touro College in NewYork. At around the same time, a pioneering patent waspublished in the Netherlands, which described the pro-duction of cultured muscle cells in a three-dimensionalstructure, “free of fat, tendon, bone and gristle.” Healthyas this may seem (nobody wishes to find unexpectedfragments of bone in a succulent cut of steak), it is animportant fact that it is primarily the fat and connec-tive tissue that give striated muscle its meaty textureand appetizing taste. Many of the recent converts tohealthy eating will already have experienced somethingsimilar. Rather than purchasing ready-made hamburg-ers, it has become popular to buy lean, red meat andmake the burgers at home. Lean meat makes a dry andhard burger, but for best results the meat needs to belaced with fat—or “well marbled” as the cognoscenti liketo say. Without the fat, the homemade hamburgers arenot as appetizing. The promised fat-free culture ofmuscle fibers will not give us beefsteak.

LET’S GET CULTURED

The culture of muscle fibers introduces a new para-dox. Striated muscle is formed when maturing precur-sor cells fuse and lose their identity, therefore each fi-ber is multinucleate and cannot itself proliferate. Newmuscle tissue arises only from the fusion of the precur-sor cells. The original Dutch process envisages the pro-duction of a collagen matrix (the basis of connectivetissue) with muscle cells that are artificially inducedto divide. In 2001, John F. Vein took out U.S. Patent No.6835390 for “A non-human tissue engineered meatproduct and a method for producing such meat prod-uct.” Vein proposed to produce cultured meat by grow-ing colonies of muscle and adipose cells in an integratedmanner that could imitate beef, chicken and fish prod-ucts. That might yet prove to be an answer. In the fol-lowing year, a paper for Tissue Engineering by Jason

Matheny (who went on to found New Harvest) andcolleagues launched a discussion of the feasibility oflaboratory-grown meat. And in 2008, the board ofPeople for the Ethical Treatment of Animals (PETA)announced a $1 million prize for the first company torelease a food product that successfully brings cul-tured chicken meat to consumers in at least six U.S.states by 2016. Governments are starting to becomeinterested. In 2007, the Dutch government invested 2

Under a high-powered phase contrast microscope, the elongatedprecursor cells are conspicuous. However, because these are inearly development, no striations are visible, which would be afeature of mature muscle cells. Striations have been seen only withimmunostaining, so these represent the early stages of research.

Prof. Bernard Roelen of Utrecht University in the Netherlands hascultured stem cells from porcine voluntary muscle. Some differentia-tion can be seen in this low-power view under phase contrastmicroscopy. (Micrograph color has been optimized by the author.)

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million euros in cultured meat research at the univer-sities of Utrecht, Eindhoven and Amsterdam. Then, inApril 2008, the Food Research Institute of Norway helda pioneering conference on cultured meat, and mat-ters began to gain momentum at last.

In the U.S., there has been less interest. The Na-tional New Biology Initiative, announced by the Na-tional Academies in September 2009, promised muchin fields such as genomics and applied genetically modi-fied technology by bringing together physicists andengineers, computer scientists and chemists with the

bioscience community. Systems biology lay behindthis. The problem here is that these are familiar andfashionable sciences, not new and exciting ones. Mypersonal belief is that we need a greater emphasis onwhole cell biology, rather than more reductionism, andthose American authorities did not propose to fundwork on cultured meat. Their initiative sought to raisethe international profile of American science, but it doesso by looking backwards (or sideways at best). It is tothe far future that we need to gaze, and the productionof cultured meat is a clear candidate for high prioritysupport. One of the few research scientists working inthis field in the U.S. is Dr. Vladimir Mironov at theMedical University of Charleston, S.C. The researchteam has already identified the myoblasts from edibleanimals that they can clone, and they have developeda method of biofabrication of spheroids of culturedmuscle cells. Their techniques could be scaled up.

When there is a product, what should we call it?The generally accepted term is in vitro meat, though exvivo has attracted some currency, and my personalpreference of “cultured meat” is useful in that it is aterm that is meaningful to a wider public. All newscientific procedures need abbreviations, of course.Already we have “single cell protein” (SCP) and “meatprotein production system” (MPPS). Now the first ac-ronym, “in vitro meat production system” (IMPS)—imps?—sounds like gremlins at work. There must bebetter alternative acronyms. One could call the emerg-ing discipline “biologically extraneous edible food fromscience-based technological extruded alternative cell

Australian artists Oron Catts and Ionat Zurr maintained cultures of “prenatal sheep skeletal muscle and degradable PGA polymer scaffold”(left) for four months as part of the “Tissue Culture and Art Project” at the University of Western Australia. Catts, Zurr and Guy Ben Ary alsopresented an example of cultured muscle called “Study for Disembodied Cuisine” (right). Separately, James King, an American designer, isnow making “cultured meat” creations of his own. Scientists find it curious how much attention the subject is attracting in the art world.

Catts and Zurr produced tissue cultures during a researchfellowship in the Tissue Engineering and Organ FabricationLaboratory at Harvard Medical School.

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kinetics,” but this gives us an acronym that is alreadyin use. There is a serious need to find a convenient termfor this novel concept. I find “cultured meat” to be aperfectly satisfactory term, but a marketing executivemight well propose something better than that. A gen-erally accepted term is a prerequisite for widespreaddiscussion on the focus for new research.

There are potential health benefits of culturedmeat. Domesticated farm animals deliver levels of satu-rated fats that are considered unhealthy. With culturedmeat, we could arrange for optimum levels of omega-3 and omega-6 oils in the products, for instance, andregulate their ratios. That’s the good news, but thereare practical problems to face. Culture would need tobe sterile and meticulously monitored. Excretorybyproducts are generated by animal cells in culture,just as they are in those growing in the living animal,and they require high throughputs of oxygen andwaste gases. They also generate heat energy, whichcould be a useful byproduct. These are major issuesthat need sensible management policies, and in myview, we now have an increasing need for the newtechnology of cultured meat. It could produce a poten-tially healthier product and at a lower financial andenvironmental cost.

RECIPE FOR TASTIER MEAT

The need to reconcile the product with the sheercomplexity of muscle as found in the animal is a prob-lem we can tackle in several different ways. The emer-gent discipline of biofabrication allows us to assemblecells into an appetizing and nutritious product. This isa fast developing technology, and it even has a dedi-cated new journal, Biofabrication. If we can perfect thistechnology, then genetically modified gene-splicingcould permit us to produce cultured forms of meat withthe very best lipid spectrum, which can appeal to con-sumers of the future. One line that I would advocatecenters on stimulating stem cells to grow in activelydifferentiating communities, which lead to the devel-opment of fully formed and diverse tissues that, in acohort, produce a naturally differentiated tissue. Be-cause the mammalian embryo manufactures a fullyformed limb from stem cells, we could ultimately dothe same in the laboratory. The fact that some adultsalamanders (but not all) can already do this showsthat this is a practical problem we can solve.

Pioneering progress has already been made by theTouro College team with tissue culture of muscle fromCarassius auratus, which has scored well with a panel.They only smelled it, mind you, because there was not

enough to taste. The name may not be familiar, be-cause C. auratus is a version of the Prussian carp, knownto us as the common goldfish. No, it’s not going to feedthe world, but this is a tissue source that can be raisedwithout incubators, and it offers proof of concept. Celllines, like the creatures from which they originated,are mortal and will normally die out after a predeter-mined number of mitotic divisions. This is known asthe Hayflick Limit and is related to the telomeres, situ-ated at the ends of the chromosomes, which becomeshorter with each mitosis and are correlated with thesenescence of the cell. As the telomeres shorten, so doesthe life of the cell line.

This is all understood, but less well known is thatsome cells break the rule. Occasional cell lines areknown to be immortal. The familiar house plant Tra-descantia zebrina is reproduced vegetatively and doesnot exhibit senescence, even though there must be mil-lions of tons of essentially the same plant around theworld, all of them many decades old. Some animal celllines have also acquired immortality. Cultures of trans-formed HeLa cells are used in laboratories around theworld. These were originally obtained from an Ameri-can hospital patient named Henrietta Lacks who wassuffering from cervical cancer. Mrs. Lacks died on Oc-tober 4, 1951, yet her cells exist in laboratories aroundthe world, and there must be hundreds of tons of hertissues still living. They have taken so well to culturethat they are a frequent contaminant of other cell lines,and they now have the longevity and virulence of aculture of microbes.

In the Netherlands, there has already been inter-personal controversy triggered by the research. Onesenior scientist, Prof. Willem van Eelen, was quoted inScientific American in June 2011, as saying that he didn’tknow what useful work the government funds weresupporting. “The researchers are talking, talking, talk-ing—every year taking more money,” he was reportedas saying. In Utrecht, a cell biologist who had workedon cultured meat was quick to respond: van Eelen wasbeing naive. “He had the idea that you could put musclecells in a petri dish and they would just grow, and ifyou put money into a project, you’d have meat in acouple of years,” retorted Dr. Bernard Roelen.

Curiously, one of the most far-reaching researchprograms came, not from scientists, but from Austra-lian artists. At the University of Western Australia’sCentre of Excellence in Biological Arts at the School ofAnatomy and Human Biology, there is a group work-ing on a “Tissue Culture and Art Project.” Two artists,Oron Catts and Ionat Zurr, have been working withcultured cells. Catts has taken it all seriously. He has

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been research fellow at the Tissue Engineering and Or-gan Fabrication Laboratory at the Harvard MedicalSchool, Massachusetts General Hospital in Boston andvisiting scholar at the Dept. of Art and Art History atStanford University. He is currently Visiting Professorof Design Interaction at the Royal College of Art in Lon-don. He and Zurr have speculated on the “semi-livingsteak” and “victimless leather.” I would like to tell themthat there’s nothing “semi” about the living steak, andvictimless leather may be a misnomer. Leather is abyproduct, after all, and not the reason cattle, sheepand pigs are slaughtered—but that’s equivocation.These two artists have done more to advance thinkingin this field than many of the professional scientists.

SUCCESSFUL APPROACHES

We can now see that there will be three approachesto growing animal tissues in bulk in our quest for newfoodstuffs. A successful product can be reliably pro-duced by 1) regularly replenishing the culture withfresh cells, 2) using an immortal cell line, or 3) immor-talizing an existing cell line. Cells derived from an ani-mal malignancy—like HeLa cells—are amenable toculture. They would provide a good starting-point,however the “yuck” factor would deter one from in-vestigating the possibilities of using a cell line of trans-formed malignant cells to produce food.

Embryonic animal stem cells seem to me to be an-other candidate, and progress has been made by cul-

turing myoblasts on a scaffold of collagen. There havebeen experiments with adipose tissue-derived adultstem cells (ADSC), which are isolated from subcutane-ous fat and can differentiate into cells including myo-blasts, chondrocytes, adipocytes and even osteocytes.When you culture cells from the intima of blood ves-sels, they show signs of organizing themselves intotubular structures, so we can see that my aim—grow-ing structurally organized complex tissues with theirown network of blood vessels—is not so impracticable.

Beneath it all lies the way in which the single cellsbehave, and little has ever been discovered about theformation of new muscle tissue. One focus of interestis the repair of damaged muscles, and the nature of thekey cell types involved is being revealed by Dr. AmyWagers and her colleagues at Stanford UniversitySchool of Medicine. They have located myogenic satel-lite cells from which new muscular tissue will derive.These cells live underneath the basal lamina of maturemuscle fibers. They are not the only cell types to beinvolved. As you might expect—in such a complexstructure as muscle—stem cells from other sourcesmay be involved in the production of blood vessels,nerves and connective tissue. The satellite cells are notjust of one type, either. They seem to be a mixed com-munity covering many different phenotypes, each ofwhich may have its own role to play. It may be thatthe study of human muscle regeneration will help toinform us on the most propitious approaches to use inculturing meat.

An intermediate stage in our progress towardsindustrialized meat production may be the growthof animal cells (much as fungus hyphae are cultured)and texturizing them to acquire a meat-like texture.The development of the existing meat substitutes hasgiven us a good grounding in techniques that allowus at will to alter the “mouth feel,” as food technolo-gists call it. The mass-production of cultured animalcells would allow the manufacturer to incorporatefibrous collagen, admixtures of striated muscle tis-sue and adipocytes (or fatty components derived fromthem) so that the meat product is made in the pro-duction plant through bio-assembly, rather thangrowing it like an explant. In this way, we could main-tain full control over taste, texture, consistency andthe nutritive value of the product could be assured.Even if we cannot culture anatomically complex tis-sues, this bioassembly technology will allow us toproduce meat substitutes from cultured components.This has been the approach used by Henk Haagsmanand his team at Utrecht, whose research funding wasrecently renewed by the European Union, as well as

One of the few American scientists involved in cultured meat is Dr.Vladimir Mironov (left) of the Medical School of South Carolina atCharleston (pictured with Dr. Nick Genovese). Mironov is lookingto develop an in vitro production model for cultured meat that canbe scaled up if it could be made commercially viable.

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Mironov’s team in the U.S. The Americans are cur-rently exploring methods of preventing their tissuespheroids from fusing together as they develop. Theyare also developing an edible polymer on which cellcommunities could be assembled. Mironov is cur-rently working on the design of a continuous-flowculture plant that could show the way to producesuch cultured meat on an industrial scale, though thisresearch has yet to be published.

ENVIRONMENTAL BENEFITS

This is all happening at exactly the right time.Cultured meat would address so many issues. Becauseit would be sterile, there would be an end to the out-breaks of the emergent diseases transmitted bymanual contact (E. coli O157:H7 and Listeria, for ex-ample). Because the meat would be locally produced,it would reduce the amount of transportation requiredto deliver the product to the consumer, with a conse-quent reduction in carbon dioxide emissions. The re-duction in cattle-rearing would cut the volume of meth-ane released into the atmosphere from the rumen ofcows. (Methane is more than 20 times more efficientthan carbon dioxide as a greenhouse gas, even thoughit is far less abundant in the atmosphere.) And theunsustainable levels of waste nitrate that are releasedby cattle farms would also be reduced.

We would not be faced, as once I imagined, withan industrial complex in the Arctic producing super-abundant food for all. But, just as the world’s popula-tion reaches unmanageable limits, it could offer a wayof providing highly nutritious, safe and affordablemeat products for the communities of the future. Itcould alleviate shortages, reduce pollution, cut humandisease and offer a way to increase food production aswe seek to ease the pressures on the world’s dwin-dling resources. Cultured meat offers us so much. Oncescience starts to see our food as a community of cells,and not just as a hunk of protein on a plate, the rate ofprogress can only increase.

When a future generation looks at how the racewas won, they will be surprised at the time it tookscience to wake up to the realities. Cultured meat willprove to be as important in the future as bread, cheese

and beer have been in the past. They too were all madeby harnessing the power of the living cell. Above all, itis the cell that matters.

And if it is the cell that matters in creating ourfood, can it be any cell at all? The range is wider thanyou might think. It could even include E. coli, which isabundant in sewage. In Japan, the Tokyo Sewage Com-pany was aware of the vast volume of E. coli cells thatcomprise one third of the huge mounds of sewagesludge they handle each day. Could this not be a valu-able food resource? They reportedly commissionedProf. Mitsuyuki Ikeda of the Okayama Laboratory inTokyo to develop an artificial steak from E. coli cells.

The experiments worked. The cells were separated,cultured, textured and cooked, and taste panels thor-oughly approve of the result. These synthetic steaksare 63% protein, 25% carbohydrate, 9% minerals and3% lipids. It is an ideal analysis. But is the public goingto start buying this revolutionary new product? Cur-rently, it’s pretty doubtful, but in the future, when foodis scarce, attitudes may have to change.

A sign on the refrigerator in the Okayama Labora-tory reminds people of the project for which it is in-tended: “shit burger,” it says. I’ve encountered a goodnumber of those in the past, but this is the first timeanybody has openly admitted the fact.

Japanese scientist Mitsuyuki Ikeda holds the artifical steak hedeveloped from E. coli cells found abundantly in Tokyo sewage.Could this be a revolutionary solution to future food shortages?