2. Contents
Introduction
Methods of flaying
a) Large ruminant
1.Combined Horizontal & vertical method 2.Vertical method
b) Small ruminant
1.Combined Horizontal & vertical method 2.Vertical method
Advantages of combined horizontal & vertical method
Disadvantages of combined horizontal & vertical method
Advantages of vertical method
Disadvantages of vertical method
Definitions
3. Introduction:
Stunning of the animal is done by mechanical, electrical or
chemical method followed by sticking/bleeding of the animal and
then flaying/skining is done.
Flaying is defined as removal of a skin/hide from a carcass of
slaughtered or dead animal.
Hide is one of the precious product obtained from the slaughter
of animal used for the preparation of leather goods.
Price of hide depends upon the quality of hide.
To obtain quality product specific scientific methods are
proposed to avoid unnecessary cuts in hide which reduces the
quality of hide.
4. Flaying/skinning should be done within a few hours of the
animal's death as the skin will peel off especially easily.
Make sure the knives used are sharp.
Methods of flaying
1. Combined Horizontal & vertical method
2. Vertical method
5. Combined horizontal & vertical methods
Head:
After bleeding, while the
animal is still hanging from the
shackling chain, the horns are
removed and the head is skinned.
The head is detached by cutting
through the neck muscles and
the occipital joint.
Hang the head on a hook.
6. Legs.
Remove skin and the legs
at the carpal (foreleg) and
tarsal (hind leg) joints.
The forelegs should not be
skinned or removed before
the carcass is lowered on to
the dressing cradle or the cut
surfaces will be
contaminated.
The hooves may be left
attached to the hide. Fig. Correct line of cutting for
hide removal
7. Clear the skin carefully
from around the vent
(anus) avoiding puncturing
it and cut the abdominal
wall carefully around the
rectum.
Skin the tail avoiding
contamination of the
skinned surface with the
hide.
Raise the carcass free of
the floor and finish flaying.
8. Vertical methods
High-throughput plants have overhead
rails which convey the carcass from the
sticking point to the chills.
Hide removal is carried out on the
hanging carcass.
The operations are as in the combined
horizontal/vertical method, but as it is
not possible to reach the hide from
ground level more than one operator is
needed.
A single operator may work with a
hydraulic platform which is raised and Fig. Pneumatically operated
lowered as required. rotating knives (flayers)
speed the removal of the
hide from the flanks
9. Automatic hide pullers are used in
high-throughput slaughterhouses.
Some types pull the hide down from
the hind, others from the shoulders
upwards toward the rump.
Automation of hide removal reduces
contamination since there is less
handling of the carcass and less use
of knives.
Moving overhead rails also improve
hygiene by reducing carcass contact
with operators, equipment such as Fig. Flaying knives are
dressing cradles and with each other used for the more
intricate parts of hide
since carcasses are evenly spaced. removal
10. FLAYING/SKINNING GOAT/SHEEP
Ripping is the process of tearing the
skin to start the skinning process.
Steps in the ripping:
One long and straight incision from
the jaw to the anus along the center line
of the belly.
Four circular cuts around the shanks
at the level of the knee and hock joint.
Two cuts on the inside of the forelegs,
knees to the breast bone.
Two cuts on the back of each hock
joint to a point mid-way between the
anus and scrotum.
11. Combined horizontal/vertical method
The animal is turned on its back and cuts are
made from the knuckles down the forelegs.
The neck, cheeks and shoulders are skinned.
The throat is opened up and the gullet (food-
pipe) is tied off.
The skin on the hind legs is cut from the
knuckles down to the tail root.
The legs are skinned and the goat/sheep is
hoisted by a gambrel inserted into the Achilles
tendons.
The pelt is then pulled down over the
backbone to the head.
12. Moving cratch and rail system.
The hanging carcass is lowered on to a horizontal conveyor
made up of a series of horizontal steel plates, bowed slightly
and divided into sets large enough to cradle a single animal.
Two operators usually work together on each lamb
performing the legging operations and opening the skin to
the stage where it can be pulled off the back. When the
gambrel is inserted into the hind legs it is hoisted on to a
dressing rail.
13. Vertical Method
Flaying/ skinning of sheep and goats
can be started by making a small
incision on the inside of one of the hind
legs.
The hind legs, including a small
portion of the skin covering the
abdomen and edges of the butt round
the rump, can be flayed with a knife
and fist while on the floor.
The carcass should then be hoisted.
14. Cont…..
To hang a sheep/goat by its back legs, find the large tendon
that connects the lowest leg segment with the rest of the leg.
Poke a hole in between that tendon and the leg bone at hock
joint.
Use your fingers to feel the lump that is created by the
double jointed bone.
Then sever the lower leg at the lower of the two joints.
Cut skin and tendons around the joint, and then snap it over
leg.
15. CONT…..
Skinning is a straight forward activity if one follows the body's
built in guidelines because the skin and muscle tissue are
naturally separated from one another by protective
membranes.
The skin easily separates from the meat along these
membranes when you pull it.
After getting a clean start, there is little risk of tearing the skin
or the meat.
Sometimes, the belly skin is removed using a knife leaving the
surface of the carcass with close serrated scores.
16. Cont….
When we use a knife to slice the skin
from the animal we inevitably violate
these layers and make the whole job
harder.
Once you cut into the meat, we are no
longer working with the natural division
between meat and skin.
We usually end up removing large
chunks of meat, as well as putting cuts
and holes in the skin.
These cuts (also called scores) and
holes open up and enlarge
easily, increasing the amount of work at
every stage of the tanning process later
on.
18. The butcher must take care to
frequently wash his hands and arms and
not touch the dirty outside of the animal’s
skin while removing the skin this way.
An alternative to fisting is the use of
compressed air. If facilities are
available, a compressed air pipe is
introduced between the skin and carcass
surface and the air pressure gradually
detaches the skin.
The air must pass through a filter in
order to reduce the micro-organisms
present in the air, which otherwise can
constitute a source of contamination.
Blowing air into the cut in the hind leg is
a traditional practice in many areas when
the skin, usually goat skin, is required as
a water bag
19. A knife should not be used in the final phase. The flayer uses his
weight with downward pressure to remove the skin especially
from the tail area, the neck and forelegs.
After the skin is separated, remove any meat and/or fat from the
skin. Wash flesh side if contaminated with blood and/or gut
contents. Then immediately cure with common salt or by air
drying to prevent putrefaction.
Removal of fat and flesh Salting Frame drying
20. Advantages of Combined horizontal & vertical method
1. Less chance of contamination of meat with skin during
flaying.
2. Less mechanisation required as during finishing of flaying
animal is brought in horizontal position.
3. More efficient, less time consuming, less labour required.
Disadvantages of combined horizontal & vertical method
As it is combination of both the position horizontal and vertical
carcass is interchanged as and when required hence have no
practical disadvantage.
It is more complicated to practice.
21. Advantages of vertical method:
Hoisting the animal makes it easy to use one’s body weight
to pull the skin off.
It also assures that the meat will stay clean.
The slaughtered animal can either be hanging from the
neck or from the legs.
Knifing is not required, fisting is sufficient and better option
to avoid scores.
Fisting is hygienically critical.
22. Disadvantages of vertical method:
It is not possible to reach the hide from ground level more
than one operator is needed.
A single operator may work with a hydraulic platform
which is raised and lowered as required.
Automatic hide pullers, dressing cradles and more
mechanization required.
23. DEFINITIONS:
Curing: The treatment of skins with common salt or by air drying to
prevent putrefaction.
Defatting: The removal of unwanted fatty (adipose) tissue from the
flesh side of a fresh skin during fleshing.
Flay cuts: Damage caused by careless use of a knife during
flaying, sometimes cutting through the skin.
Flaying (skinning): The removal of a skin from a carcass.
Flaying knife: The knife used to sever the subcutaneous tissues
when removing the skin from the carcass.
Flesh side: The inner side of a skin next to the body of an animal
in life.
24. Fleshing: The removal of the residual connective and
adipose tissues from the flesh side of a skin after flaying.
Gouges: Knife damage to the skin during flaying, taking
out scooped portions of the corium.
Grain layer: The top portion of the dermis.
Pattern: The pattern of skin when laid out flat.
Putrefaction: Bacterial and enzymatic breakdown, rotting.
Scores: Knife damage to skins during flaying by cuts that
do not fully penetrate through the skin.
Trimming: Removal of unwanted portion of a skin.
