“The history of making fibers from protein goes back about 150 years. People tried chicken feathers, soybeans, and other plant proteins. But they proved too weak to spin, did not hold together well, and were too costly to produce. When polyester and other synthetic fibers that are cheap to produce came to the market, [protein-based fibers] disappeared. Our lab has worked on some other alternative biomaterials: We discovered a squid gene that’s similar to silk that we were able to spin into fibers. But we realized that that, too, was expensive, and that we’d run into the same problems that bioengineered silk companies ran into.

“Biomass fermentation is a great answer to both cost and the climate. It lowers land use and the carbon footprint. We looked at tapping into waste fermentation generated by breweries and pharmaceutical production. Our goal was to remove the protein from the yeast using an enzymatic method, then spin the resulting solution into fibers. The solution dissolves in an organic solvent and can be converted into fibers. This is the same process used to create wool fibers. We make the protein in the U.S.; the fibers are made in Europe, where we knit our sweaters. Our first batch is 50% wool and 50% fermented fibers. 

“In looking to create industries that are more aligned with nature, this kind of biomanufacturing should become a reality. We have the technology for it, we’re being advantageous in terms of land use, energy use, and raw materials. And production costs are very low: around $6 for an annual production of 7,000 metric tons compared to $10 to $12 to produce fine wool. What we need is governmental regulation to support a shift away from fast fashion.”