1-5.
DEFEATHERING--PICKING AND SINGEING
a. Picking. While they are still warm from scalding, the carcasses are
defeathered. Two types of pickers are currently used:
(1) Drum. The chickens remain shackled and are moved along a line
through a series of drums with rubber fingers set so that each series of drums removes
feathers from a specific area.
(2) Cyclomatic. This looks like a large centrifuge. The chickens
automatically drop off the shackle and rubber fingers pick off the feathers until the
chickens reach the edge of the picker. They are then returned to the center of the
picker and the process is repeated. When all the feathers are removed, the chickens
drop from the picker and are reshackled. In this method, the chickens keep moving so
they have fewer disjointed or broken bones. This type of picker takes up less room in
the plant.
b. Singeing. The chicken is next singed to remove hair and feather particles
missed by the picker.
1-6.
EVISCERATING
a. After singeing, the chickens are eviscerated (see figure 1-3), i.e., the entire
intestinal tract, respiratory tract, liver, spleen, heart, and ovaries and oviduct (or testes)
are removed. The oil sac from the base of the tail is also removed, though this is not a
part of the viscera.
b. The giblets are separated out from the viscera. The liver is separated from
the gallbladder, the lining removed from the gizzard, and the pericardium from the heart.
c. Chickens are eviscerated while still warm since the viscera is easier to
remove. Once the carcass has cooled, the flesh becomes firm, and the digestive juices
attack the intestinal wall and give the meat an off-flavor.
1-7.
CHILLING
Following evisceration, the carcasses and giblets are chilled, either with ice and
water (ice slush) or with air.
a. Ice-and-water (ice slush) chilling is the most practical because it removes the
body heat rapidly, reduces shrinkage, and bleaches the carcass, which improves its
appearance. There must be enough ice so that ice remains in the vat after it is filled.
The best way to chill freshly slaughtered chickens is by ice and water with air agitation.
Air agitation of ice slush improves its chilling capacity. One of two methods is used to
chill with ice and water.
MD0713
1-6