From henhouse to your house

Last reviewed: January 2010

The government's food-safety rules require chicken processors to identify "critical control points" where contamination might occur, then establish procedures for preventing, eliminating, or reducing those hazards. As our tests show, nothing guarantees a clean chicken. The contamination rate can vary with what the birds are fed, the preventive measures used, growing conditions, and the time of year, says Michael Doyle, Ph.D., director of the University of Georgia's Center for Food Safety. The procedures differ among plants; those outlined here are a possible scenario.

Illustration of a chick that just hatched
Illustrations by Keith Negley

In the hatchery

Some chicks are contaminated with salmonella from their mothers or their own shells during hatching. Others ingest bacteria from their surroundings. Live birds infected with campylobacter or salmonella usually show no symptoms. To reduce the risk to people, some companies vaccinate hens and chicks against salmonella.

Illustration of a chicken house

In the chicken house

Usually a new flock of thousands of chicks is trucked to a house run by a farmer according to the poultry producer's specifications. Chickens habitually peck the ground, ingesting bacteria from litter and feces, and could be exposed to vermin. Companies try to keep germ carriers away and continuously monitor the flocks' general health. Antibiotics are used to prevent or treat illness and might also be given to speed chickens' growth. But treated birds can't be sold as USDA-certified organic.

Illustration of a truck

On the road

Chickens travel to the processing plant in cages. Filth can spread.

Illustration of a processing plant

Processing plant

See In the processing plant

Illustration of a truck

After processing

Companies take steps to ensure their packaged chickens are properly refrigerated during shipping and delivery to market. Federal regulations require transport at a temperature no higher than 40° F.

Illustration of packaged meat

In the store

Improper temperature or handling can introduce bacteria or cause them to multiply.


In your kitchen

Illustration of man and woman eating dinner at kitchen table

Cooking chicken thoroughly, to at least 165° F, and washing anything that comes in contact with raw chicken greatly reduces risk.

  • In the processing plant

    Birds are stunned, killed, and bled.

  • Scalding
    Illustration of steaming hot water
    Hot water loosens feathers for easier plucking. Some bacteria on feathers, feet, and skin are killed, but others float from one bird to another. Carcasses are washed. Critical control point Check temperature and pH of water.

  • Illustration of feathers
    A machine's rubber fingers pluck feathers and remove the outermost layer of skin. Contaminated fingers can spread bacteria from carcass to carcass.

  • Illustration of a hand holding a magnifying glass
    USDA visual inspection
    After internal organs are removed, a Department of Agriculture inspector checks carcasses and viscera for signs of disease, bruises, and other defects.

  • Washing
    Illustration of a showerhead with liquid sprinkling out
    Birds are sprayed with chlorinated water or other washes to reduce bacteria and are checked for visible fecal matter. Chickens that pass muster are chilled; those that fail are reprocessed or discarded. Critical control point Record chlorine level and adjust if necessary.

  • Chilling
    Illustration of a thermometer with snow flakes around it
    To prevent spoilage, carcasses are submerged in icy chlorinated water or air-chilled to lower their internal temperature to 40° F or less. When chickens emerge, USDA inspectors grade them for quality. At this stage, the USDA conducts salmonella testing, and the plant conducts one test for E. coli per 22,000 birds. Critical control point Monitor chlorine level of chiller or temperature of air-chill room; check internal temperature of birds.

  • Cut-up and packaging area
    Illustration of a chicken with dotted lines breaking it into sections
    Birds are cut into pieces if necessary, packaged, and shipped. Critical control point Check for metal fragments in packaged poultry.