A row over working conditions has escalated since the 2 Sisters Food Group bought the Carlisle ready meals maker in April 2011.
The poultry supplier, which is the empire of Ranjit Boparan, wants 800 permanent staff to accept reduced rates of pay for overtime and bank holiday working plus reduced rights to sick-pay and redundancy.
The Union of Shop, Distributive and Allied Workers (USDAW), which represents the staff, said industrial action had not been ruled out but that staff were trying to avoid it.
USDAW area organiser Jayne Shotton said: “People are really, really angry that the new owner is doing this. They can’t see any justification for it – the site is in profit.
"These are conditions fought for over the years.”
Emloyees rejected 2 Sisters’ initial proposals but agreed to offer a compromise package at the meeting.
USDAW met staff to put the new proposal together.
The compromise would maintain the overtime rate but agreed to a cut in bank-holiday pay that was lower than the reduced rate that 2 Sisters had suggested.
Shotton told FoodManufacture.co.uk that members had agreed to reduce their double time pay for working Sundays to time-and-a-half, and overtime for all hours worked over eight hours in the day during the week from time-and-a-half to time-and-a-quarter.
Employees had also agreed to reduce their overtime paid for Bank Holidays from basic plus double time to time and a half.
They have agreed to reduce their rights to sick pay.
2 Sisters is now considering the compromise.
It will give its decision on Thursday July 12.
Shotton said workers at 2 Sisters' chicken plant in Scunthorpe had also rejected the firm's proposals for reduced terms and conditions of employment.
“They [2 Sisters] are trying to take staff back to statutory and basic rights,” said Shotton.
2 Sisters would not comment on the compromise proposed today. A spokesman told FoodManufacture.co.uk: “The consultation is ongoing. It’s all about being competitive.”
In the 2012 Sunday Times Rich List, Ranjit and his wife Baljinder were ranked 101 with an estimated fortune of £285M.
2 Sisters acquired Northern Foods with a cash bid of £342M.