But even as the plant-based sector has made a small dent in the overall meat market, there’s another new alternative out there—and it comes from laboratories. One company that’s making these products is Air Protein, which creates its meat using microbes, air, and carbon in an environmentally friendly process akin to fermentation. Another, Upside Foods, uses animal stem cells and feeds them nutrients to create its wares, including cultured meatballs, chicken, and duck.

These companies’ products are often referred to as “lab-based meat,” “petri-dish meat” or “in-vitro meat,” but their founders have a preferred term: “cultivated meat.”

“Ultimately, [the product] is at the stage where it’s being grown in production facilities like breweries. And nearly every food that we eat that comes off the shelf is going to go through some food company’s lab for testing, so we just don’t think the [lab-based meat] nomenclature is right,” said Dr. Uma Valeti, the founder and CEO of Upside, at the Fortune Brainstorm Tech conference in Half Moon Bay, Calif. this week. 

Both Valeti and Dr. Lisa Dyson, the founder and CEO of Air Protein, swear that their meats are just as tasty as what you’d get straight from an animal. But what they’re really excited about is the benefits their companies will provide to the environment. Dyson said Air Protein’s method is actually carbon negative “from cradle to plate,” takes less time than the two years required for a cow to grow to eatable size, and requires much less land usage than farms that produce cattle and plants for meat alternatives. 

“You look at the water utilization — if you compare it to soy, it’s going to take a soy farm the size of Texas to give you the same amount of proteins you get from an Air Protein farm the size of Walt Disney World,” she said, also noting that the food industry is one of the largest sources of greenhouse gas emissions, with one cow having the same carbon footprint as a car.

The holdups for both companies right now are scaling their operations, getting FDA and USDA approval, and convincing consumers to try their products. “We’d like to define it not as the source, but as the experience,” said Dyson, who says eaters really want is texture and flavor, as opposed to caring about how it was made. 

Valeti noted that Upside has done thousands of taste tests with “experts in food, culinary chefs, and the meat industry” and opened a lab in Emeryville, Calif. to show people how its product is made. The facility also highlights the ways cultivated meat is much more cost-effective than traditional farming.

“We can reduce logistics enormously because we don’t have feed loss,” he said. “We don’t have a slaughterhouse. We don’t have the safety issues that come with having herds of animals intensely confined. But in order to get to scale, we need to have public-private partnerships and continued investment in the field. I have enormous optimism that this is an opportunity not to miss for any stakeholder who cares about impact food and economic opportunity.”

When cultivated meats are eventually available, there’s one question both founders can expect to be asked repeatedly: Are your products vegan? Dyson’s answer was a clear yes, while Valeti had a more complex response.

“Candidly, I think we’re going to challenge the definition of veganism and what veganism actually means if you become a vegan because of animal welfare and environmental reason,” he said. “If you are vegan because you just don’t want to eat anything animal-based, we are animal-based. We are animal cells. So I think we’re going to challenge the definition and there’ll be more very large conversations on the philosophy behind the definition of vegan.”

This story has been updated to correct the spelling of Lisa Dyson’s last name and to correct her statement about whether Air Protein’s products are vegan. She says they are.