Cargill Inc. announced the biggest step in the unwinding of its Black River Asset Management subsidiary with the spinoff of most of its assets into a new private equity firm called Proterra Investment Partners.

The firm, led by managing partner Rich Gammill, will manage funds that are now worth $2.1 billion. Cargill said Monday it will continue to be an investor in the Proterra funds.

Proterra also retained the smaller partners in the Black River funds and the commitments of those funds.

Proterra is currently based in Hopkins in Black River's former offices, but plans to make its headquarters in downtown Minneapolis.

The firm chiefly focuses on agriculture and food-related investments. It has $782 million in three ag-focused funds, $1.2 billion in three food-focused funds and $165 million in one fund focused on metals and mining.

"Our team has worked together to serve clients for nearly a decade, identifying global private equity investment opportunities in the important sectors of agriculture, food and metals and mining," Gammill said in a statement. "We look forward to maintaining the relationship we have developed with Cargill over many years."

Cargill announced in September that it would shut down Black River by separating its operations into three companies. The former Black River commodity trading operation was placed inside Cargill's risk management operation.

Proterra is the largest of the new, separated firms. It employs 49 people and also has offices in London, Shanghai, Sydney, Singapore, New Delhi, Sao Paulo and Buenos Aires.

Black River's decision to break itself up came after the firm shut down four hedge funds last summer, paying out $1 billion to its investors. Black River, which was created a dozen years ago, managed more than $7 billion before the fund closures and subsequent breakup.

Staff writer Mike Hughlett contributed to this story.