Greencore added that a range of social distancing measures, hygiene procedures and regular temperature checks are in place at the factory.
"We are doing everything that we can to keep our people safe," said Greencore.
It comes as 10 members of staff tested positive for the virus at fruit wholesalers Fyffes in Coventry.
A spokesman for Fyffes told Coventry Live: "The management of Fyffes Group Ltd is working closely with the Public Health team at Coventry City Council and Public Health England (PHE) Midlands, following a number of confirmed cases of Covid-19 among people working at our Coventry facility.
“The safety of all our workers is our number one priority and a number of actions to tackle this outbreak have been agreed and are currently being implemented.”
Food factories have hosted an unusually high number of Covid-19 outbreaks around the world and experts say the cold, sunless environments, cramped working conditions and staff who are more likely to use public transport may be ideal for the virus to spread.