Christina Agapakis is a synthetic biologist and postdoctoral research fellow at UCLA who blogs about about biology, engineering, biological engineering, and biologically inspired engineering at Oscillator.
When you factor in the fertilizer needed to grow animal feed and the sheer volume of methane expelled by cows (mostly, though not entirely, from their mouths), a carnivore driving a Prius can contribute more to global warming than a vegan in a Hummer
. Given the environmental toll of factory farming it’s easy to see why people get excited about the idea of meat grown in a lab, without fertilizer, feed corn, or burps. In this vision of the future, our steaks are grown in vats rather than in cows, with layers of cow cells nurtured on complex machinery to create a cruelty-free, sustainable meat alternative. The technology involved is today used mainly to grow cells for pharmaceutical development, but that hasn’t stopped several groups from experimenting with “in vitro meat
,” as it’s called, over the last decade. In fact, a team of tissue engineers led by professor Mark Post at Maastricht University in the Netherlands recently announced their goal to make the world’s first in vitro hamburger by October 2012
. The price tag is expected to be €250,000 (over $330,000), but we’re assured that as the technology scales up to industrial levels over the next ten years, the cost will scale down to mass-market prices. Whenever I hear about industrial scaling as a cure-all, my skeptic alarms start going off, because scaling is the deus ex machina of so many scientific proposals, often minimized by scientists (myself included) as simply an “engineering problem.” But when we’re talking about food and sustainability, that scaling is exactly what feeds a large and growing population. Scaling isn’t just an afterthought, it’s often the key factor that determines if a laboratory-proven technology becomes an environmentally and economically sustainable reality. Looking beyond the hype of “sustainable” and “cruelty-free” meat to the details of how cell culture works exposes just how difficult this scaling would be. Cell culture is one of the most expensive and resource-intensive techniques in modern biology. Keeping the cells warm, healthy, well-fed, and free of contamination takes incredible labor and energy, even when scaled to the 10,000-liter vats that biotech companies use. In addition, even in those sophisticated vats, the three-dimensional techniques that would be required to grow actual steaks with a mix of muscle and fat have not been invented yet, though not for lack of trying. (This technology would primarily benefit our ability to make artificial organ replacements.) Add on top of that the fact that these three-dimensional wads of meat would have to be exercised regularly with stretching machinery, essentially elaborate meat gyms, and you can begin to understand the incredible challenge of scaling in vitro meat.
Cell culture is hideously expensive, not to mention technically difficult.
Even beyond this mechanical engineering issue, when we consider the other raw materials, the nutrients that will feed and sustain these stem cells as they grow into our dinner, the large-scale sustainability of in vitro meat can be called into question. In fact, of all the fantastic claims of lab-grown meat, the most far-fetched given current technology is that in vitro meat will be cruelty-free. In vitro meat proposals imagine a “donor herd” of cows that will give some cells to make meat without having to be slaughtered, so yes, the first in vitro hamburger, if it is successfully unveiled this October, will be made of cells that started out as just a few cow muscle stem cells from a still-living cow. But the donor cells aren’t the only animal product needed to grow in vitro hamburgers; the growth medium that provides nutrients, vitamins, and growth hormones to the cells is currently made with a mixture of sugars and amino acids supplemented with fetal bovine serum
---literally the blood of unborn cows. Of course, many tissue engineers are trying to come up with cheaper and cruelty-free alternatives to fetal calf serum. Algae is currently a much-trumpeted replacement: Best-case-scenario analyses
of the environmental impact of algae-fed cell culture estimate that in vitro meat will have 78-96% lower greenhouse gas emissions than conventional meat. Algae are remarkable organisms, and they are especially important because their photosynthetic efficiency, the rate at which they convert sunlight into sugars, is significantly higher than plants like corn. This efficiency allows for the production of the same amount of stuff in a much smaller area, with fewer inputs. So why don’t we use algae to feed cows already? Why isn’t algae solving all of our problems? Well, this isn’t the first time that algae has been proposed as a solution to an environmental crisis in food production. In the 1940s and 1950s, as the population exploded and conventional agriculture didn’t seem like it could keep up, enormous research efforts went into scaling the production of algae as a food product, a high-protein green paste to feed to increasing number of hungry people around the world. A fascinating article
by Warren Belasco in Technology and Culture traces the history, the promise (and hype), and the failures of this research, and provides valuable insights for the current attempts to “save the world” with algae. Scaling, it turned out, killed these plans the last time we tried them. Scaling algae production in open ponds proved an enormous challenge, with the gains in efficiency fading as the controlled environment of the lab was traded for ponds where cells crowded and shaded each other while having to fight off infections and predators. At the same time as algae failed to deliver, the Green Revolution
significantly improved yields of conventional crops, and algae was slowly transformed into a specialty product rather than the base of the food pyramid. Today, algae is used to produce extremely high-value health-food products, like omega-3 fatty acids and carotenoids, with the average market price for algae products at around $150 per pound of dry cells produced
. Compared to the price of corn, which is about $0.09 per pound
, or beef at $1.99 per pound
, algae has a long way to go before it can play the role of cheap feedstock for in vitro meat production. Grand technological fixes can look good if you don’t peer too close at their workings. But as should be clear once you examine the case of in vitro meat, the meat problem won’t really be solved with flashy tech, even if it could somehow displace factory farming on sheer economics. The real issue is the ever-growing demand for meat, and our unwillingness to eat less of it, regardless of the environmental cost. Perhaps someday soon we will be able to outgrow our taste for flesh, not by producing it artificially or by genetically engineering people to be disgusted by meat
(another far-out fix) but by changing the price of meat to reflect its true environmental cost. So, with that in mind…$330,000 hamburger, anyone?
Meat image via Shutterstock, cell culture image via Shutterstock.
