Food processing methods and a food processing system are provided which minimise microbial growth while an animal, such as a chicken, is processed into food. During processing, the temperature of an animal carcass and the atmosphere surrounding the carcass are controlled by spraying gases and a mixture of ozone and water on the carcass, directing the gases through a passage in a wall to cool a processing area, and flowing the gases into the atmosphere surrounding the carcass. Preferably, the gases include ozone and cryogenic gases recycled from a cryogenic freezer. The system uses a reduced amount of fresh water by recycling water used during food processing.