July 29 (Reuters) - United Airlines (UAL.O) said on Thursday it was moving forward with plans to outsource its catering operations following a six-month review, similar to other airlines" strategies. United said it has selected three suppliers to operate the airline"s five kitchens and oversee menu design and administration. The airline"s staff were informed of the decision in a memo reviewed by Reuters. 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 the memo. "We wanted to proceed in a way that allowed us to protect the vast majority of jobs for our United catering team members, and invest in solutions that significantly improve our customers" onboard experience," United"s VP of customer innovation and strategy and catering, Mandeep Grewal, told staff. 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.