Miller, who has been the company's chief growth officer since 2004, will return to London to take up the new job. She was previously based at the consumer goods giant's world headquarters in Pittsburgh.
Barden is moving to a strategic-planning position in Europe. He was appointed to head up the UK in September 2003, and was previously responsible for turning around the Heinz Salad Cream brand.
Miller is a food industry veteran, with 17 years of management experience at PepsiCo and Bestfoods, responsible for a number of businesses.
Born in Peoria, Illinois, she holds a degree in Russian from Knox College and an MBA degree from Southern Methodist University.
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