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Standing in a kitchen in San Francisco, in a state where foie gras is illegal, Josh Tetrick cuts into the pale gray pate anyway and smears it on a thin piece of bread. “You prettied it up a little bit,” he says to a bearded chef, pointing his butter knife at the plate, “what’s going on here?”
“Little carrot and vanilla puree,” says the cook. “Little beet, little bit of a splatter there to mimic the atrocity that we’re taking away.”
Tetrick chews on the delicacy. “Even though I’m not a foie expert,” he says, “I’ve been eating a little bit more foie outside the state of California for the past handful of months, and it tastes like foie should.”
It tastes like foie gras 应该 because you could make the argument that it isn’t really foie gras. Because this is no ordinary kitchen—it’s also a lab. Tetrick is the CEO of Just, a controversial food company formerly known as Hampton Creek, whose entire board quit last year. And his scientists here grew the meat in the lab from cells, incubating them with heat and feeding them nutrients. Compare that to getting foie gras the old-fashioned way: force-feeding a duck or goose until its liver balloons to up to 10 times its normal size.
Scientists have been culturing meat in labs for years, but Just and other startups like Finless Foods, which is growing fish meat, have been feverishly pursuing this so-called “clean meat” of late. Just is chasing a cultured chorizo and a cultured nugget in addition to the foie gras. And Tetrick claims his startup has finally made the process cost-effective enough to take to market: At the end of this year, he says, Just will officially introduce an as yet undisclosed lab-grown meat, the first time the stuff will hit shelves.
The challenges of engineering meat in the lab is one thing, but convincing consumers to turn away from the storied kill-it-and-grill-it method of eating is another. And while it’s easy to imagine how lab-grown meat would be better for the planet, there’s actually little data to back that up.
Whether or not Just makes it to market this year, and whether or not their meat tastes and smells and feels like meat, the era of clean meat is approaching. (Just declined to let us taste their food, saying it wasn’t ready for public consumption.) Soon enough, burgers will grow not just in fields, but in vats. Farther down the line, your T-bones may not come from a cow, at least not in the traditional sense. If the sound of that bothers you, know that you’re not alone.
There’s Got to Be a Better Way
The promise of lab-grown meat isn’t to stop eating animals—it’s just to eat way, way fewer of them. In America alone, we consume 26 billion pounds of beef a year. That demands a massive industrialized livestock system that is problematic for the planet. One cow can consume up to 11,000 gallons of water a year. Worldwide, livestock may be responsible for 15 percent of greenhouse gas emissions. And the system rarely has the animals’ best interests in mind.
But cultured tissue offers a way to potentially grow many meals’ worth of meat from just a handful of cells. Under the right conditions in a lab, cells can be encouraged to divide just like they do inside the body—cutting down on natural resources, gas, and animal rights abuses. “Theoretically from one little piece of meat you can create an unlimited amount,” says Mike Selden, CEO of Finless Foods.
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The precise methods vary between labs and companies. “In practice, it doesn’t work the first time—you’ve got to try a bunch of different things to get it to work,” says Selden. At Finless Foods, they take a bit of fish meat and filter it for a particular kind of cell, not so much stem cells but stem-like cells, what they’re calling progenitor cells. “We’re looking for cells that have the ability to differentiate into different lineages,” says Selden. “So we’re looking for cells that are stem enough."
The idea is to trick these cells into thinking they’re still in their owner. So by feeding them nutrients like salts and sugars, Finless can get the cells to turn into muscles or fat or connective tissue. Think of it like sourdough yeast: Once you’ve got a starter strain, you can keep making a distinctive bread. “Once each of these companies has a cell line going,” says Selden, “they never have to go back to the initial animal.”
Creating that starter strain is harder than it sounds, though. The media that these companies are using to get the cells growing is expensive, largely because in addition to providing salts and sugars, they have to give the cells protein. That’s typically done with serums made from animal blood, which are very, very pricey—just an ounce of fish serum will set you back $850. And the blood of animals really isn’t the ideal basis for a new kind of sustainable, cruelty-free meat. (Especially if you’re using fetal bovine serum, which is exactly what it sounds like: blood taken from tiny cows.) It’s been holding the clean-meat industry back, big time.
Finless won’t divulge the composition of its medium, but does say that since September it’s reduced its serum usage by 50 percent. The struggle, then, is to perfect a medium that provides protein without animal serum. “When we begin selling products we will absolutely have no serum whatsoever,” says Selden. “That’s not just because of any PR thing or environmental reasons. Cost-wise the economics of it make absolutely no sense.”
It’s not an insurmountable problem. “In theory, all of the precursors and nutrients found in serum could be brought together from isolated sources,” says biochemist and chef Ali Bouzari. In particular, serum provides what are known as growth factors, proteins that signal the cell to divide. “I imagine there are a lot of very precise ratios and components that are integral to promoting optimized cell growth,” he says.
Over at Just, Tetrick claims his company has cracked that code. Their cell media is free of serum, he says, and therefore far cheaper. What exactly is in that magic mix, they won’t say.
You Know What They Say About Assumptions
If what Tetrick says is true, that would be a gigantic step forward for lab-grown meat, which has struggled mightily with costs—a lab-grown burger introduced in 2013 cost a cool $330,000 dollars. But even if lab-grown meat is economically sustainable for these companies to produce, that doesn’t necessarily mean it will be more environmentally sustainable than traditional livestock for people to eat.
Clean meat companies claim the process will be more efficient because you’re only growing the bits you need to feed people—no guts or eyeballs or brains. And without the need for massive livestock operations, you could theoretically spread out your manufacturing facilities, cutting down on transportation emissions. But few studies have looked rigorously at the environmental pros and cons of in vitro meat production.
What scientists really need is something called a life cycle analysis. It would tabulate all the things that go into making food, like water, land, and greenhouse gas emissions. “It’s very easy to say, for example, ‘Well I don’t know, in vitro doesn’t use as much land as beef cattle production,’” says Alison Van Eenennaam, an animal geneticist at the University of California, Davis. “OK, but that’s just one component of a life cycle analysis.”
Or you might say that because you don’t have cows burping up methane, you cut down on greenhouse gas emissions. But one of the few studies that Hsa been done on the subject found that you’d actually end up using more energy to produce clean meat than you would raising cows. After all, this is essentially a new wave of industrialization, which means you’ve got to keep the lights on. Another study, though, found clean meat would come out on top.
Of course, even if lab-grown meat is both environmentally and economically sustainable, that won’t make it the de facto choice for producers 或 consumers. Around the world, animal agriculture is a way of life for a billion people, who use livestock for more than just meat. “A petri dish can’t provide manure and it can’t pull a plow and it doesn’t provide a source of banking and trade for those people,” says Van Eenennaam. “I don’t know that it’s going to have a huge impact in the developing world, where most of the demand for milk and meat is projected to happen in the next 20 years.”
And then, of course, there’s the issue of taste.
Perfecting a mushy meat like foie gras or chorizo is one thing. But growing a steak is an entirely different problem. You can’t just grow it in a vat—you have to worry about muscle cells and fat cells and connective tissues all working in precise concert. That and you’d somehow have to get a constant stream of nutrients to the cells at the center of the steak. (The vascular system in your body accomplishes this nicely.)
“We are super, super far away from whole-muscle meat,” says Bouzari. “And we are blindingly far away from whole-muscle meat of the same quality that you can find from animals that are allowed to move around and breathe and experience a diverse set of biological stimuli.”
Like the cows raised by California sustainable meat company Belcampo, which does it the old fashioned way, or at least as close to it as they can. The cattle roam outside and, lucky for them, get to breed naturally. “I don’t see clean meat as being competition for us at all,” says Anya Feldon, CEO and founder of Belcampo. “It’s going to take a village to open everyone’s eyes to what’s wrong with our food system, so I see it as an ally in this fight.”
Not everyone has the luxury of eating luxuriated cows, though: McDonald’s alone sells 75 hamburgers every second. “The first company to get within spitting distance of a fast food taco is going to be on the cover of WIRED,” says Bouzari. Will clean meat be perfect at first? Almost certainly not. But hey, that’s what condiments are for.