The data comes from a fact-finding mission by the British Sandwich Association (BSA) on around 40 companies in its membership.
The constant staff turnover costs the baking and sandwich industry in recruitment and training.
According to Jim Winship, director of the BSA, the problem stems from employees not seeing food manufacturing and catering jobs as long-term career options.
He said: “The industry needs to look at how they make their sector more attractive as a career prospect.”
The situation could worsen, he believes, as the improving economy and more job openings encourage staff to leave their current position.
In order to change perceptions, Winship said the industry must offer good training and career opportunities and make sure these are clearly communicated.
“I think the industry, in a way, has not put enough into training people,” he said, adding: “We need to shout about some of the opportunities in the industry which we’ve been very bad about.”
Pay and staff benefits have been a much-discussed topic of late, with the coming of the National Living Wage next April and many companies announcing pay rises.
Starbucks has also offered those who have worked for the company for over a year an interest-free loan to pay a rental deposit.