Weetabix, which employs 2,000 people at its sites in Burton Latimer and Corby, is in consultation with the unions over plans to cut costs.
The cereal company has told workers it is seeing eroding margins..
In a briefing document answering questions from the trade union Usdaw, Weetabix said: “We are seeing a continued decline in the cereal market through the main supermarkets. This decline is more significant than we anticipated.
“Volume can be sold through the discounters, however they expect significantly lower cost products therefore eroding margin.”
A statement from Weetabix said: “The Weetabix Food Company is consulting with its trade union representatives to explore potential changes to shift patterns and associated payments.
“Weetabix has a strong working relationship with all of its trade unions and our colleagues at our Burton Latimer and Corby sites.” Weetabix, which also makes Alpen, Weetos and Ready Brek, was family-owned until 2004 when it was bought by London-based private equity company Lion Capital. They sold a 60 per cent stake to China’s Bright Food Group in 2011.