ATLANTA — PepsiCo Inc., which lost Subway Restaurants as a major fountain customer last year to Coca-Cola Co., has won the beverage and snack business of Quiznos Corp.

The new agreement will end the sandwich chain's 23-year relationship with Coke, dating to the company's start in 1981 in Denver. The company's new deal begins in February, covering 3,600 restaurants in the United States and Puerto Rico.

Quiznos executives said they were troubled by Coke's recent agreement with Subway, one of its biggest rivals in the $440 billion restaurant industry's competitive sandwich category.

"Pepsi will treat us with the attention that a leading brand deserves," said Trey Hall, chief marketing officer at Quiznos.

Quiznos already sells chips and other snacks from Frito-Lay, a PepsiCo unit, alongside other brands. Frito-Lay is expected to make up a larger percentage of Quiznos' business under the new deal while the conversion to Pepsi soft drinks and noncarbonated drinks should start early next year, according to Pepsi.

Dan Schafer, a spokesman for Atlanta-based Coke, said, "We value our relationship with Quiznos, and we believe we could help drive their business better than any other beverage partner. But we were unable to reach agreement on a relationship that would bring value to both partners."

Denver-based Quiznos, and Pepsi, of Purchase, N.Y., declined to discuss terms of their multiyear agreement. These agreements typically span eight to 10 years.

Quiznos is the third-largest sandwich chain in the United States behind Subway and Arby's.