Beyond Meat CEO Ethan Brown discusses the evolution of plant-based burgers, the science of protein, why his company avoids GMOs, and its mission to help create a more sustainable food system.

Here is a lightly edited excerpt of Verge editor-in-chief Nilay Patel and Brown discussing Beyond Meat’s decision to use pea protein in the latest episode of The Vergecast.

So I want to get really nerdy about pea protein.

Yeah, we happen to use it today, but we might not necessarily be using it tomorrow. It’s what’s available to us. We really use that because it’s available in significant quantities in a way that some other proteins aren’t. But in my view, from a consumer perspective, the thing that recommends peas most strongly is what it’s not — and it’s not soy.

The consumer told us very early that they wanted to avoid having additional soy in their diet.

Why is that?

People have concerns about different types of ingredients. And there’s different conflicting medical literature about different types of ingredients. So if there’s a controversy or disease or discomfort with a particular ingredient, I don’t want to complicate my product with it. So we looked for another source of protein very early.

Peas are available in this level of supply because they were set up for starch. This particular process of separating protein from fiber was scaled up to sort of the starch market. But there’s nothing magical about peas. You can get protein from any number of resources, and one of the products I’m really excited about is our breakfast sausage that is protein from sunflower seeds and protein from mung beans and protein from brown rice as well as pea protein.

So you’ll see us continue to diversify the number and amount of proteins that we use. Five years from now, you’ll be able to go to a meat counter and get sausage that is not only made from pea protein but from lentil protein, lupin, or your favorite protein source.