Memphis Meats, the subject of Inc.'s November cover feature, is a company most readers won't have heard of before, and for good reason: It doesn't expect to be selling its product to consumers for a couple more years.

Memphis Meats grows meat--beef, chicken, and duck--in a lab, thus producing slaughter-free meat. While founder Uma Valeti and his team have already succeeded in growing such protein in their "bioreactors," there's a long way to go before they can do it efficiently enough to compete on price and taste with what you find in restaurants and in supermarkets.

The startup's low public profile is what made it so remarkable when a slew of the world's most famous investors -- including Virgin founder Richard Branson, Microsoft co-founder Bill Gates, and former GE CEO Jack Welch --  poured $17 million into Memphis Meats in August. The Series A funding represented more than three times what the company had raised previously. Just as important, perhaps, was the name recognition and imprimatur of the investors.

Branson, who has long mixed business with philanthropy, told me he sees clean meat as a powerful tool for combating global warming, a cause close to his heart (and closer than ever since Hurricane Irma laid waste to his Necker Island in September).

"An overlooked part of climate change is cattle in particular and livestock generally, and the amount of meat our dogs and cats eat and so on," he said when I spoke with him recently. "So if we can replace meat, or replace live animals, without killing animals, that must be the most wonderful, utopian future, and if we can do it quickly enough, it may be just in time to save the remaining rainforests."

Branson himself gave up eating beef in 2014 to bring his diet more in line with his personal ethics. As an investor, he's not all-in on Valeti's belief that only real meat, rather than a vegetable-derived alternative product, can sate the world's growing demand. Both he and Gates are investors in Beyond Meat, which produces veggie burgers that reproduce the flavor of beef patties more closely than has been possible in the past. Gates is also an investor in Impossible Foods, which offers a similar product. 

"I've had a lot of fun on Necker Island serving juicy hamburgers to everybody at the dinner table and watching their faces as they said, 'This is the best hamburger I've ever eaten,' only to be told it was all vegetarian," Branson said, laughing. 

"Both approaches work," the mogul behind Virgin continued. "The challenge now is we've just got to multiply up the quantities as rapidly as possible."