More than 500 jobs are at risk after Bakkavor announced it is considering closing one of the salad factories at its Spalding site.
A spokesman confirmed that the company is considering ceasing operations at Factory 1 at the West Marsh Road site and changing night shift patterns within the Deli.
Functional support roles across the site will also be reviewed and reduced.
More than 500 employees will be affected by the proposals.
The firm is blaming the loss of business and the impact of the COVID-19 pandemic for the changes.
The spokesman said: “We can confirm that we are entering into several consultations with employees at our Spalding site where we have two salads factories, two meals factories and a distribution centre.
“Over the past 12 months the salads businesses at Spalding (Factory 1 and the Deli) have come under increasing pressure due to the impact of a business loss at the beginning of 2020 and more recently the impact of the COVID-19 pandemic crisis.
“As a result, we have had to make some difficult decisions to ensure we can continue to remain sustainable in what remains a particularly difficult trading environment.
“We are therefore proposing to cease operating Factory 1 and change the night shift patterns within the Deli.
“We are also proposing to change how we manage operations across the site which will involve reviewing and reducing functional support roles.
“There are over 500 employees impacted by these proposals.
“We believe these changes are fundamental to the future success of the site.
“If these proposals go ahead, wherever possible we will try to find alternative roles for those impacted across our other Lincolnshire sites or within the group.
“We would like to thank all of our colleagues for their commitment and professionalism during this difficult time.”