A spokesman for Allied Bakeries confirmed that Sykes had left the company last week, adding that she had wanted to pursue other interests.
Her departure, he said, had been a mutual decision and she had not yet decided what she wanted to do next.
Sykes joined Allied Bakeries as marketing director in December 2002 to drive the growth of brands such as Kingsmill, Allinson, Sunblest and SunMaid. She was previously a marketing manager for Pedigree Masterfoods, dealing with dog food. Before that, she was responsible for the marketing of PZ Cussons’ Imperial Leather.
Jon Wilson, head of marketing for Kingsmill, will replace Sykes on an interim basis until a replacement is recruited.