The manufacturer, part of 2 Sisters Food Group, produces sandwiches, sandwich fillings, salads and bread products, and supplies customers including Tesco and Costa Coffee.
One worker at the site told British Baker that his pay had been cut by £40 a week since last year, but that management and senior staff had recently been awarded a 2% pay rise.
He added that the company had recently landed a £3m deal with Sainsbury’s and had been recruiting hundreds of additional staff.
A spokesperson for 2 Sisters, said: “We are aware that a ballot has been called with regards to the site collective agreement, which may result in an overtime ban. While we are disappointed that the ballot has been called, our discussions with union and employee representatives will continue.
“2 Sisters Food Group operates in a highly competitive environment and, as a major supplier to all of the UK’s leading retailers, we continually need to ensure we deliver the highest quality at the lowest cost, particularly with trading conditions remaining challenging at this time and with high food inflation, due to higher commodity costs for the ingredients we buy to make our products.”
The spokesperson added that supply to its customers would not be affected as a result of any ban.
It is thought around 600 workers are being balloted.