Earnings reports on Tuesday from three prominent restaurant operators, including Chipotle Mexican Grill, illustrated the impact of the changing preferences of American consumers.

Sales at Chipotle, the restaurant chain that has come to symbolize the tastes of the millennial generation, continued to break the billion-dollar barrier in a single quarter, despite a problem with its pork supply that caused some of its more than 1,800 stores to run short on carnitas.

Brinker International, which operates Chili’s and Maggiano’s, said it was hoping further investments in technology to build customer loyalty would help it sustain and build sales, which climbed 3.3 percent, to $784.2 million, in its third quarter, which ended March 25.

Yum Brands, the company behind KFC, Taco Bell and Pizza Hut, continued to struggle to regain its footing in China, where sales remain weak after one of its meat suppliers was hit last year with a food safety scandal.