What is meat? You might say it's simple: water, fat, muscle, connective tissue — you know, all that tasty-sounding stuff.

But those at the forefront of developing cell-cultured meat have a different idea. Maybe meat is the product not of killing animals but of cultural consensus.

At the center of Chase Purdy's briskly paced and quietly bold Billion Dollar Burger: Inside Big Tech's Race for the Future of Food is Josh Tetrick, a San Francisco-based entrepreneur and CEO of Just Inc. Tetrick's company and a handful of others like it are growing cell-cultured meat that tastes, feels and looks like the livestock-harvested meat that people are used to — except without the farms and killing of animals. And before anyone raises a skeptical brow: Yes, it's actually meat. Technically, at least. The struggle for mainstream acceptance of cell-cultured meat is real. Convincing the American public that cells grown in "serum" in a big vat is meat will be challenging, but it could happen — and sooner than you might think.

Meat, it seems, is all about what consumers are used to. For the sake of the planet and the future of food sustainability, it might be time to reconsider meat harvested from dead animals. If we're going to eat meat at all, eliminating the need to kill an animal that consumes food resources humans could otherwise be using — and that's also captive to an industry that pollutes the air and soil and deforests broad swaths of the planet — might be a good start.

One of Purdy's strengths is his ease in exposition. He can even be charmingly teacherlike at times. Take, for instance, how he describes how cell-cultured meat is grown, starting with cells taken from a live animal.

"The scientists at cell-cultured meat companies identify which cells are stem cells. Whereas ordinary cells have limited utility, stem cells can divide and multiply many times, and they can transform into any of the more than two hundred types of cells that operate within animal bodies.

Think of our cells as individuals on a building construction site. Some are assigned to lay cement, some are trained as carpenters, and another might be an electrician. Together, they work harmoniously to build different components of the larger structure. But it is possible to pluck a cement worker from her job, send her to classes where she'll learn about wiring, plugs, and sockets. Then she can be sent back into the field as a newly trained electrician. The same thing can happen on a molecular level."

That's not all though. Scientists grow those cells in a kind of liquid. Because lab-grown meat doesn't have blood to circulate nutrients like living bodies do, scientists at Just and companies like it use a kind of "serum" that contains sugars, lipids, hormones and amino acids, as well as many hundreds of proteins that carry out functions such as transporting insulin, which helps grow cultured vertebrate cells, or transferrin, which delivers iron to cells. Oh, and all this takes place in vats that can look straight out of a brewery.

In covering the business side of cell-cultured meat, Purdy could have written a hagiographic account of Tetrick and Just; refreshingly, he chose not to. This could have been another Steve Jobs-type story no one needs, where a visionary has a great idea that will change the world and then, after the world gets changed — wait for it — said visionary gets really rich too. Then, as Americans, we're left undecided as to whether we admire the accomplishment or the wealth more. Instead, Purdy's book reads more realistically, like the teasing out of a tangled dance among entrenched meat producers, a few ambitious start-ups, early pioneers, regulatory complications and consumer skepticism.

It's the lack of heroes that, in part, makes this such an interesting story and topic. Tetrick knew from his early years that he cared about animal welfare and that he wanted to do something good for the world. He drifted through law school and still was unsure about a proper course for his life. He decided on cell-cultured meat as a cause and business because he saw opportunity and it aligned with his values — and so he decided to take it. And in the depiction of Tetrick, Purdy is careful to allow him to tell his story, as well as capture others' stories of him, some of which are unflattering. Meat, however, stays front and center in this story. It keeps you hungry.

Still, there's the moral and ethical matter of manipulating nature to serve human ends. Sure, other forms of this kind of manipulation go by the names "civilization" or "technology," but the issues arising from cell-cultured meat aren't minor. Essentially it's cloning. Purdy asks Peter Singer, a Princeton University bioethics professor and the author of Animal Liberation, whether growing meat in vats violates the natural order and if he has a problem with it. "No, I don't, to be honest," Singer says. "I think we can and always have striven to do better than nature. ... I don't think nature is in any way a gold standard."

Alice Waters, famous chef of Chez Panisse in Berkeley, Calif., sees things differently. She tells Purdy: "I really think of my food as deeply connected to nature. It has to do with seasonality; it has to do with a complexity of soil that grows the vegetables that the animals eat. I think it's what nourishes us." This might be true, but most people don't (and can't) get their meat locally sourced, even if that would be ideal. Sustainable consumption of meat might just require more cell-cultured meat than its livestock-harvested antecedent.

Purdy rightly leaves the humans vs. nature debate aside, though, after teasing out the positions, and gets back to the big question: What is meat? Philosopher Friedrich Nietzsche wrote that "there is no feast without cruelty," but he clearly did not live to see the still ambiguous but encouraging promise of cell-cultured meat. Meat, oddly enough, might just be what we agree meat is. Heretofore it was the flesh of a dead animal. Now it can be engineered in a lab to have the same properties that a living animal's flesh would have.

If the taste and texture are the same and if the cost is manageable, why not? Now, when someone says, "It tastes like chicken," you can say: "It is chicken." It's grilling without the killing.

Nicholas Cannariato is a writer and editor based in Chicago.

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