United Airlines all-female crew

An all-female United Airlines crew poses before taking off for a round-trip flight out of Denver International Airport. 

As many as 454 Denver-based United Airlines workers could be impacted by outsourcing its catering operations, the firm reported to the State of Colorado Friday.

The company announced the move last week after a six-month review. It chose three suppliers to operate its five kitchens and oversee menu design and administration. Employees in good standing would be offered a job at one of the future suppliers and about 70% would continue to have union representation, according to a memo to employees obtained by Reuters.

“At the end of the day, we wanted to proceed in a way that allowed us to protect the vast majority of jobs for our United catering employees, and also put United on a path toward further developing world class kitchen capabilities by investing in solutions to significantly improve our customers’ onboard experience,” according to a United letter sent to the Colorado Department of Labor and Employment Friday, signed by Mandeep Grewal, United's vice president of customer strategy innovation and catering.

The letter stated Gate Gourmet, a unit of Zurich, Switzerland-based gategroup , would take over the kitchen at Denver International Airport.

Gate Gourmet issued a press release with the news Friday.

“(The firm) will support United’s operations and culinary aspirations through a diverse selection of services including hub operational support, on-trend menu design and passenger culinary experience, each designed to enhance the United Airlines experience,” according to the release.

“gategroup has a known reputation for superior culinary and retail experiences and innovation,” said United's Grewal in the release. “Our shared commitment to operational excellence will allow for best-in-class menu design concepts and advance our capabilities to best serve United’s customers.”

Unite Here is the union representing Gate Gourmet workers, as well as existing United kitchen workers at DIA.

“Gate Gourmet has committed to offer employment to United’s frontline catering operations kitchen employees who remain in good standing, providing job security for our valued employees,” Grewal’s letter to the department stated. “… We are confident that a large percentage of our employees will receive offers to join Gate Gourmet.”

United expects to initiate the transition in October - when federal payroll aid that prohibited airline job cuts expires - and be working with its new partners by mid-November.

Reuters contributed to this report.