Processing hides, guts and keratin-containing raw materials

1. TECHNOLOGY OF MEAT AND MEAT PRODUCTS

2.  Skinning. Characterization and structure of the
skin
 Skinning technology
 Defects of leather raw materials
 Processing of intestinal raw materials. Gut
characterization
 The technology of processing intestinal raw
materials
 Defects of intestinal raw material and product
 Processing of keratin-containing raw materials

3. Skin is called skin with a hairline. From the skins of adult
slaughtered animals that are sent to meat processing plants
(cattle, small cattle, pigs, horses, camels and deer) for
processing, leather semi-finished products are made for the
manufacture of shoes, clothes, leather goods and saddlery,
machine parts and devices. The skins of young animals
(calves, kids, lambs) are used for the manufacture of semi-
finished fur products.
Depending on age and gender, skins from cows, bulls and
calves are classified as follows:
sklizok - the skin of unborn or stillborn calves;
piers - the skin of young cattle, which is milked;
outgrowth - the skin of young cattle that have mastered plant
food;
rite - the skin of cows;
bovine - skins, castrated bulls;
Boogain - the skin of uncastered bulls.
Depending on the size of the hides, pigs are divided into: small
30-70 dm3, medium 70-120 dm3, large over 120 dm3. Boar skins
are not in demand and are not processed due to the poor
quality of leather fabric.
Skins of small cattle (sheepskin) - are divided by the length of
the coat into sheepskin wool (wool length over 6 cm), half-
woolen (2.5 - 6 cm) and shank (up to 2.5 cm).

4. The structure and properties of the hide on different topographic sites are not
the same. On the skins of cattle, the following areas are distinguished: head,
collar, slippers, floors, paws, flanks, rumps, tail. The skins of other animal
species are subdivided into the same areas.
The head is the front part of the skin, removed from the head, has a low
density and strength.
The crank is the part of the skin taken from the animal’s neck, has a loose
fabric with folds of various thicknesses and low strength.
The saddlecloth is removed from the back and back of the carcass, is the
most valuable part of the skin.
Rump is the lowermost section of the skin, which is part of the saddlecloth.
The tail is bordered by a tail - a section of the skin taken from the tail.
Topographic sections of pork skin differ from each other in that the thickness,
density and strength of the skin are sharply reduced from the middle of the
skin to the floors and the collar.
The skins of sheep are loose, this is due to a dense coat, an abundance of
sebaceous and sweat glands, a ton of collagen fibers, as well as a horizontal
arrangement of the ligature of the dermis.

5. The main substances of the skin are water, proteins, fat and fat-like
substances, and in small quantities carbohydrates, mineral salts and
enzymes. The skins of adult animals are denser, they have less water than
the skins of young animals; in the skins of well-fed animals more fat. The
average water content in a pair of skins (in%): piers - 71–74, rites and
bovines - 69, pork skins - 64. The amount of fat in sheep skin reaches 30%,
in cattle skin it is 0.5-1.5 %
Proteins account for about 95% of the dry residue of skins (90% of their
collagen). In the dermis of paired bovine, about 33.2% of collagen.

6. The skin consists of three layers: the epidermis, dermis, subcutaneous
tissue.
Epidermis - the surface layer is 1% of the skin thickness. The epidermis and
hair are removed during the development of the skin, and retained during
the development of the fur.
Derma - a complex weave of collagen bundles, elastin and reticulin fibers,
makes up about 84% of the total skin thickness.
Subcutaneous tissue is a type of connective tissue that contains blood
vessels, elastin fibers and a lot of fat cells. The subcutaneous tissue of pigs
is called mezdra.
The hairline of cattle skins is called hair, pork skins - bristles, sheepskin -
wool. Hair (bristles) includes a root located in the depths of the skin, and a
shaft that protrudes freely above its surface. The root of the hair ends with
the expanded part - the bulb; it lies in a hair bag formed by the epidermis
and connective tissue of the dermis.
Hair bags in pork skins penetrate the reticular dermis and enter the
subcutaneous tissue, resulting in leaking pig skin.

7. Types of skins
In accordance with the species and age
characteristics, leather raw materials are
distinguished:
 shallow
 large
 pork

8. Small leather raw materials
Small leather raw materials
include:
 skins of young cattle
(mucous membranes,
cuppings, regardless of
weight and outgrowth of
up to 10 kg);
 skins of sheep unsuitable
for fur and fur production;
 hides of goats.

9. Large leather raw materials
Large raw materials include:
 skins of cattle (half-skin - skin of a dodger
and a bull-calf weighing 10-13 kg);
 goby (skin of a goby weighing 13-17 kg);
 rites (light 13-17 kg, medium 17-25 kg,
heavy - over 25 kg);
 bovines (light 17-25 kg, heavy - over 25
kg);
 bull (light 17-25 kg, heavy - over 25 kg).

10. Pork Leather Raw Materials
Pork raw materials include skins of domestic and
wild pigs, hogs and wild boars with bristles
◦ from 30 to 70 dm2 - small,
◦ from 71 to 120 dm2 - medium,
◦ from 121 dm2 or more - large,
◦ skins of boars with an area of more than 80
dm2
Pork grains - part of the skin taken from the
rump, back, sides and neck of pork carcasses, is
divided by size in paired state
◦ small areas from 30 to 50 dm2 inclusive
◦ large - over 50 dm2

11. hiding skins → dressing → wool removal → coats →
washing → contouring → sorting →
preserving → sorting → labeling → packaging →
storage, batching and shipping.

12. Intravital malformations of the skins include:
lumpiness (thickened rough folds on the skin
of the skin of uncastrated gobies), walrus (the
uneven surface of the front side of the pork
skins under, thick layering of the epidermis -
scab), fistulas (damage to the skin by larvae
of the gadfly), imperson (absence of the skin
of the face individual areas as a result of
mechanical damage), knives (through
piercing of the skins of sheep and goats with
prickly grass); brand (place of a burnt mark),
scratches (mechanical damage to the facial
layer). Defects due to insufficient feeding or
poor livestock: skinnyness - friability and
thinness of the skin caused by depletion of
livestock; hut - the skin of heavily depleted
sheep and goats of late winter or early spring
slaughter
Defects arising from the shooting and ritual of
hides are the wrong cut of the skin, snags,
undercuts, holes, etc.

13. For industrial processing in the
intestinal shop enter the
intestine in the form of a kit. A
kit is a collection of guts
obtained from one animal.
During processing, the
intestines are divided into parts
close in diameter, not fully
corresponding to its anatomical
departments. In this regard,
there is a production
nomenclature of the intestines
Guts

14. The intestines after their processing are used as sausage
casings. A bubble has a body, a tip and a neck; in sausage
production, a bubble with a neck is more valued. Capercaillie,
curls due to the weakness of the walls is a low-value raw
material for sausage casings. Lamb stitches can also be used to
produce surgical threads (catgut), musical and technical strings.
Treated saline intestines are stored at a temperature of 0-10 ° C
with a relative humidity of 85-90% for 12 months.

15. Keratin-containing raw materials include bristles, hair,
horned raw materials, low-value feathers and feather-down
production waste, which contain a large amount of keratin
protein (85.6-90%).
The structural peculiarity of keratin determines the specific
conditions for obtaining feed and technical products from
this raw material.
Treatment of bristles and hair. In meat processing plants,
bristle is prepared, yanked bristles with bulbs, bulbs without
bulbs, hair from the tails of cattle, ear hair from the ears of
cattle, horse hair from tails, manes, bangs, lower legs and ya
hair ( from the tail, sides and belly).
The process of processing the bristle-set includes washing,
freeing from the epidermis and drying