Mystery of Chipotle's rising tortilla costs is solved

Chipotle investors and customers are accustomed to hearing about the Mexican chain's ingredient costs. It routinely warns about the escalating price of meat and the difficulty securing adequate supplies.

But the company raised new questions when it said was spending more money on one of its most basic ingredients: tortillas.

It turns out tortillas are the only food at Chipotle that uses preservatives, and the company is looking to change that. It's increasingly switching to flour that's organic, unbleached and unenriched - adding to its expenses.

"We are always working to improve the quality of the ingredients we use, including our tortillas, and sometimes those improvements have incremental costs," said Chris Arnold, a spokesman for the Denver-based chain.

Chipotle is fixing its tortillas as the company prepares to tout its simple, unprocessed ingredients in a new marketing campaign. Removing the remaining additives from its menu may give it fresh ammunition as Chipotle criticizes the more heavily processed food of rival chains.

"There are more than 800 artificial ingredients, preservatives and processing aids used in processed foods," Mark Crumpacker, Chipotle's chief creative officer, said on a conference call. "In fact, there are 85 ingredients in a single fast-food burrito served by one of our competitors."

In this case, Chipotle hopes, less is more.