REDWOOD CITY, CALIF. — Impossible Foods, the maker of the plant-based Impossible Burger, has raised another $300 million in a Series E funding round led by existing investors Temasek and Horizons Ventures. To date, the company has raised more than $750 million since launching in 2011.

Impossible Foods said it will use the proceeds from this latest equity funding round to add a third shift of workers and second production line at its manufacturing plant in Oakland, Calif., with additional expansion announcements coming later this year. The company said it will hire at least 50 new employees at the plant, which currently employs 70 full-time workers.

“We have cracked the molecular code for meat and built an industry-leading intellectual property portfolio and brand,” said David Lee, chief financial officer for Impossible Foods. “Our global financial partners are supporting a technology powerhouse that will transform the global food system.”

The company said it is experiencing unprecedented demand for the Impossible Burger, which began appearing on restaurant menus across the country in 2016. In January, Impossible Foods debuted an upgraded recipe that is made with soy protein instead of wheat protein and may be steamed, seared or flame-grilled. The product is now sold in more than 7,000 restaurants in North America and Asia. Recently, Red Robin added the Impossible Burger to its menu at nearly 500 restaurants nationwide, and Burger King began testing its Impossible Whopper in the St. Louis area with plans to serve the item at all 7,200 U.S. restaurants by the end of the year.

The Impossible Burger is slated to launch in retail outlets later this year.

The latest fundraising round for Impossible Foods marks the largest ever for a plant-based meat company and follows a successful initial public offering by competitor Beyond Meat, El Segundo, Calif., said Bruce Friedrich, executive director of The Good Food Institute, Washington.

“The success of Impossible Foods and Beyond Meat is proof that plant-based meat has arrived,” Mr. Friedrich said. “With these two companies now valued in the billions of dollars, it’s clear that the plant-based meat market is both hot and here to stay.”

Plant-based meat, egg and dairy companies in the United States have raised more than $16 billion in the past decade, including $13 billion in 2017 and 2018, according to research from The Good Food Institute.

“Impossible and Beyond both have a vision of a meat market that puts healthier and more sustainable products in front of consumers,” Mr. Friedrich said. “Because plant-based meat is so much more efficient, the products will be less expensive at scale. That represents a truly massive consumer market — literally, everyone who eats — and so also represents a massive investment opportunity.”