Firefighters were called after a fault in the food filtration system set alight to the roof at the McCain factory in Peterborough.
Crews from Stanground, Whittlesey, and Dogsthorpe were called to the fire at the McCain food processing factory in Funthams Lane at 2.48pm on Friday, January 27.
Sprinklers were activated after the fire started in the food filtration system but it then spread to the roof.
Firefighters wearing breathing apparatus used one hose reel to extinguish the fire and returned their stations by 4.20pm.
The cause of the fire was accidental.