A major national investor in Dunkin’ Donuts has spent more than $50 million to scoop up dozens of franchises across South Florida.

And Cafua Management Co. LLC is on the hunt for real estate to open 50 more stores in the region over the next three years.

Methuen, Mass.-based Cafua closed a $50 million deal July 16 to purchase 20 Dunkin’ Donuts locations from Doral to Pompano Beach and acquire 30 additional stores in the next 60 days.

It secured financing in Boston from Northern Bank and Trust Co. in a deal arranged by Joyal Capital Management LLC.

The company plans to double that investment in the next three years and open up to 100 sites, according to Joyal, its real estate investment adviser.

“We’re aggressively seeking new real estate locations,” said Gary Joyal, CEO and managing partner of Boston-based Joyal. “We’ll lease, build and purchase to open new stores.”

The deal marks Cafua Management’s entry into South Florida. The firm is the largest Dunkin’ Donuts franchise owner in the country, with 300 stores in eight states, according to its marketing information. It’s one of a new generation of Dunkin’ Donuts investors looking to expand their holdings as veteran franchisees in the 64-year-old restaurant look for exit strategies.

The chain has grown to a nearly 100 percent franchised model with 11,000 restaurants in 33 countries. At the end of 2013, its parent company, publicly traded Dunkin’ Brands Group Inc., reported franchisee sales of about $9.3 billion.

Both companies leading the Florida expansion have strong ties to the chain, and Joyal has closed more than $500 million in franchise purchase transactions, according to its executives.

“We had a vision of what we wanted to accomplish in growing our business,” said Cafua CEO Mark Cafua. “JCM was perfectly positioned to help us achieve that goal.”