Hundreds of people turned up to protest against the closure of the HP sauce factory and the loss of 125 jobs in Birmingham on Saturday.
Heinz, the factory owner, plans to transfer production from the West Midlands to the Netherlands.
The Save our Sauce campaign has been supported by unions and MPs.
Jack Dromey, deputy general secretary of the Transport and General Workers’ Union, said the company had misled its staff.
“Heinz gave promises to keep production of HP in Birmingham, but those commitments are as thin as the sauce’s imitations,” he said.
“This march is not just about the sauce and the 125 workers whose jobs are at risk – it is about the local community, a prime British brand and keeping manufacturing jobs in the UK.”
HP is a British icon, Dromey added.
“The workers of HP are the sons and daughters, grandsons and granddaughters of other HP workers.
“They have worked at this factory which has put that bottle of sauce on our teatime tables for 100 years and we must ensure it’s there for the next 100 years,” he said.