TECHNOLOGY OF MEAT, FISH AND POULTRY PRODUCTS

TECHNOLOGY OF MEAT, FISH AND POULTRY PRODUCTS Prepared by- Mohit Jindal P a g e | 1
TECHNOLOGY OF MEAT, FISH AND POULTRY PRODUCTS
L T P
3 – 3
RATIONALE
This subject is included in the curriculum to impart basic knowledge and skills of various technologies and
equipment used for production of raw as well as processed meat, fish and poultry products, in the students
DETAILED CONTENTS
1. Introduction to Indian meat, fish and poultry industry (02 hrs)
2. Preparatory operations of meat and meat products (18 hrs)
Composition of muscle, Different types of slaughtering methods, Different types of meatents,
Antimortam and post-mortem inspection of animal/slaughtered animal, Abattoir – Definition and
construction; basic preparatory procedures (culmination, emulsification, pre-blending) Cured and
smoked meats, sausage products – classification, processing steps, and canned meat, meat pickles
3. Handling and Dressing of Poultry (06 hrs)
Inspection of poultry birds, dressing and preparation of ready to cook poultry, factors affecting the
quality
4. Egg and Egg Products (06 hrs)
Structure, chemical composition and nutritive value, spoilage of eggs and preservation of whole egg
and egg products, preparation of egg powder
5. Fish and Fish Products (06 hrs)
Types of fish, composition and nutritive value, judging the freshness of fish, fish grading and
cooking of fish, smoking, pickling, salting and dehydration, preservation of fish and processed fish
products
6. Frozen Storage of fresh and processed meat, poultry and fish (04 hrs)
7. By-products of meat, fish, poultry and egg industry (06 hrs)
LIST OF PRACTICALS
1. Demonstration of slaughtering and different cuts in meat at a slaughter house
2. Preparation of different types of meat products and their quality evaluation
3. Cutting of meat
4. Preparation of sausages
5. Calculation of shape and size index of egg
6. Preparation of ready to cook poultry
7. Retail cuts of dressed chicken

8. Calculation of hogg unit of egg
9. Measurement of air cell of egg
10. Determination of effect of temperature on coagulation of egg protein
11. Determination of moisture and solid content of different egg constituents
12. Determination of specific gravity of eggs
13. Preparation of egg powder
14. Preparation of fish, meat and egg pickle
15. Candling and grading of eggs
16. Iron sulphide formation in cooked eggs
17. Preservation of whole egg
18. Visit to slaughter houses and abattoir
19. Demonstration of filtering & staking of fish

Introduction to Indian meat, fish and poultry industry
With annual production of 53,000 million eggs and 3.2 million tonnes of poultry meat, India is now
among the biggest egg and broiler producers in the world (2010). At the current level of production, the
poultry sector contributes about US$9.3 billion to the gross national product and provides direct and indirect
employment to over 3.2 million people. India is a country where more than 65% population lives in villages
wherein about 75% people have their own livestock. Because of this livestock is important segment of rural
economy accounting.
In India goat, sheep, pig, buffalo and cattle meat constitutes nearly 75% of the total meat production.
India has acquired number one status in the world contributing around 15% of world’s milk production
during 2007-08, yet the meat production is around 2% of the world meat production.
The state of Andhra Pradesh alone produces over 30% of the country's eggs, with other top-
producing states being Tamil Nadu (15%), Karnataka (8%) and Punjab & Haryana (14%). Regionally, egg
production in the south makes up over 50% of production; north and west about equal, with Eastern India
rapidly gaining presence. Thus, it can be said that the industry, both layer and broiler, is set to grow. Per
capita consumption of eggs has already gone up to 41 from an estimated 32 in 2005.
The export of meat and meat products are very less, i, e. 1.4% of the total world meat trade. Frozen
meat accounts for 65-75% of the total export. At present access to markets in developed countries does not
exist because of animal health issues. National Meat and Poultry Processing Board is an autonomous body
launched by Government of India on 19th Feb 2009. Fresh students should note that carcass yield of meat
animals is calculated as percentage of live weight. Livestock population, meat production, slaughter rate,
export.
 The present production of meat is estimated at 6.27 million tons in 2010 (FAO, 2012), which is
2.21% of the world's meat production.
 The contribution of meat from buffalo is about 23.33%, while cattle contributes about 17.34%, sheep
4.61%, goat 9.36%, pig 5.31%, poultry 36.68% and other species 3.37%.
 The meat production has increased from 764,000 tonnes in 1970-71 to 6.27 million tons in 2010.
 The compounded average growth rate (CAGR) during the last two decades works out to be 4.5%.
 The value of meat and by-products is Rs 79,889 crore including skin and hides, while the export
value of meat and meat products work outs to be more than Rs 6,000 crore in the year 2009-10.
Dressing% = Dressed weight/Live weight x 100
It varies with species, breed, age, sex and plane of nutrition. High dressing percentage is desirable only if the
increase is brought about by muscular growth rather than deposition of excess fat.
Goat
Goat is referred as Asian Animal’ in the world livestock arena because almost 95% of goat
population belongs to the developing countries of Asia. India ranks second in the goat population which is
more than double to that of sheep. Though regarded as poor man’s cow, goat has the distinction of being the
most important meat animal of India because it provides choicest of all meats fetching maximum retail price
in the home market. However, of late relative contribution of goat and sheep meat to total meat production
has gone down.
80% of the goat breeds are medium sized, Mehsan, Surti, Gaddi, Marwari etc. The dressing
percentage of an animal of good health varies from 43to 48%. Goat meat is light red in colour and is very
firm in consistency. A Goat carcass has an abundance of kidney fat which is white in colour.
Sheep
In India, sheep are cribbed mainly for wool. Semi-arid and mountainous areas mostly unsuitable for
crop farming besides, pelt (skin) and sometimes milk are also obtained from sheep. In fact, skins from sheep
and goats are fairly valuable and about 90%are recovered from their slaughter.
India stands third in sheep population in the world. In general, sheep weigh 13 to 16 kg at 6 months
of age. A healthy sheep should give a dressing percentage of about 45to 48. Meat from sheep of less than 12

months of age is referred as lamb and that of more than 12 months of age is called mutton. Mutton has light
to dark red colour with a firm and dense consistency.
Pig
Pigs are reared for the production of pork Their growth is also very fast. Pigs have the capacity to
convert inedible feeds and garbage into nutritious and costly meat. Pigs should be slaughtered at 6 to 7
months of age. An ideal slaughter weight is approximately 50kg for desi pigs and 60-70kg for crossbred
pigs.
Dressing percentage varies from 65-70 in case of desi pigs and 70to 75%of the live weight in case of
crossbred pigs. The yield is more from pigs as compared to other species due to the presence of skin on the
carcass. Consumption of Pork is prohibited for Muslims as religious restriction.
Buffalo
India ranks first with 59% of the world buffalo population. Buffalo is milky animal and is not reared
for meat. However unproductive and uneconomic buffaloes after 5-6 Lactations find their way to the
slaughter house. Indian buffalo show a wide variation in dressing percentage and generally figures vary from
50 to 55 % of the live weight depending on the condition of the animals. Ideal age for slaughter of buffalo
calves for meat has been recommended as 18 to 24 months. Out of a total of 90 million buffaloes, almost
11%, mostly unproductive and uneconomic animals are slaughtered every but they contribute nearly 29% of
the total meal production
Cattle
In India, Cows are reared only for milk production. Slaughter of cow is banned by law in most of the slates
expect the ones ruled traditionally by communists such as west Bengal and Kerala. However, slaughter of
bullocks does take place at specific places having predominantly Muslim population. Carcass yield varies
from 50tlo 54% depending on the condition of the animal.

Structure of muscles
Muscles are made up of hundreds of
thousands of muscle cells (also called muscle
fibres). These muscle cells acts together to
perform the functions of the specific muscle
they are part of.
Unlike other tissue, muscle cells contain
myofibrils – these are shaped like long
cylinders and extend along the full length of
the muscle fibre/cell.
Each myofibril consists of two types of
protein filaments called thick filaments and
thin filaments. The thick filaments and the
thin filaments within myofibrils overlap, and the sections where they overlap and occur together are called
sarcomeres. When muscle contraction occurs, the thin filaments and the thick filaments slide past each
other.
Myofibril is the name given to cylindrical structures that extend along the complete length of each muscle
cell. Recall that "muscle cell" = "muscle fibre" = "muscle fiber" (Am.Sp.).
.Each myofibril consists of two types of protein filaments. They are thin filaments and thick filaments.
Sarcoplasm is the cytoplasm of muscle cells (which are also known as muscle fibres). Cytoplasm is a jelly-
like substance that surrounds the nucleus of a cell and is sometimes described as "the cell-matrix". It holds
the organelles in place within the cell.
It is also important to remember that the components essential for all cells (not all of which are illustrated in
the diagram above) are also present in muscle cells. More about the contents of cells generally, is available
on the page about animal cells.
Sarcolemma is the name of the cell membrane that encloses each muscle cell, specifically muscle cells
("muscle cell" = "muscle fibre" = "muscle fiber").
The word sarcolemma is formed from two parts:
 sarco- which means "flesh", and
 -lemma which means "sheath"
Sarcolemma is one of the layers of muscle tissue. Overall, the main layers of muscle tissue include:
 Sarcolemma is the cell membrane that encloses each muscle cell (which is also known as a muscle
fibre).
 Endomysium is connective tissue that wraps each individual muscle fibre.
 Perimysium is connective tissue that wraps bundles of muscle fibres - the "bundles" being known as
fasicles.
 Epimysium is connective tissue that wraps the whole muscle.
 Fascia (or "deep fascia") is a layer of thickened connective tissue that covers the entire muscle and is
located over the epimysium.
Muscle Fibre is a term that is often used interchangeably with muscle cell.

Muscle fibres are the basic functional units of muscle tissue - which is special because it has the ability to
contract, producing movement or force.
There are three main types of muscle tissue.
They are:
 Skeletal Muscle - muscles that move bones, under conscious control.
 Smooth Muscle - surrounding organs and other body structures, not under conscious control.
 Cardiac Muscle - the specialized muscle found only in the heart.
General components of Muscle Fibres/cells:
The components of skeletal muscle cells that are specific to muscle tissue are myofibrils.
 Each muscle fibre ("muscle cell") is covered by a plasma membrane sheath which is called the
sarcolemma.
 Cytoplasm is present in all living cells.
The cytoplasm present is muscle fibres (muscle cells) are called sarcoplasm.

 The sarcoplasm present in muscle fibres contains very many mitochondria, which are the
energy-producing units within the cell. These mitochondria produce large amounts of a
chemical called "Adenosine Triphosphate", which is usually referred to in abbreviated form as
"ATP".
 Sarcoplasmic reticulum is present in muscle fibres/cells and extends throughout the sarcoplasm
of the cell. The function of the sarcoplasmic reticulum is to store calcium ions, which are
necessary for muscle contraction.
 The components of skeletal muscle cells that are specific to muscle tissue are called myofibrils.
These are cylindrical structures (illustrated above) that extend along the complete length of the
muscle fibre/cell.

 Each myofibril consists of two types of protein filaments called "thick filaments", and "thin
filaments".
 Here, it is
sufficient to say
that the thick
filaments and the
thin filaments
within myofibrils
overlap in a
structured way,
forming units
called sarcomeres.
 Sarcomeres are
sections of
myofibril that are
separated from
each other by
areas of dense
material called "Z
discs".
 The "A band" is a
relatively darker
area within the
sarcomere that
extends along the
total length of the
thick filaments.
The "H zone" is at
the centre of the A
band of each
sarcomere. As
shown below, this
is the region in
which there are
only thick
filaments, and no
thin filaments.
The "I band" is
the region
between adjacent A bands, in which there are only thin filaments, and no thick filaments.
( Each I band extends across two adjacent sarcomeres.)


Composition of muscle, Different types of slaughtering methods, Different
types of meatents, Antimortem and post-mortem inspection of
animal/slaughtered animal, Abattoir – Definition and construction; basic
preparatory procedures (culmination, emulsification, pre-blending) Cured
and smoked meats, sausage products – classification, processing steps,
and canned meat, meat pickles
COMPOSITION OF MUSCLE TISSUE
Muscle tissue contains approximately 75% water and 25% solids, of which 19% are proteins. Lipids
constitute about 2.5 to 5% of muscle.
Water
This is the largest component comprising two third to three fourth of the muscle tissue. Due to polar
behavior, water molecules are attached with the electrically charged groups of muscle proteins. About 40.5%
of the total water in muscle is so tightly bound that it is almost impossible to dislocate it. Most of the water
exists in immobilized and free forms.
It may be noted that almost 70% of water content in fresh meat is located within the myofibrils.
Further, an increased water holding capacity is associated with juiciness and tenderness of cooked meat.
Protein
Muscle proteins have been broadly classified into three categories:
i) Myofibrillar proteins -- soluble in dilute salt solution
ii) Sarcoplasmic proteins -- soluble in water or very dilute salt solution.
iii) Stroma or connective Tissue proteins -- almost insoluble
Myofibrillar proteins:
These proteins constitute contractile part of the muscle and make up about 60% of the total protein in
the skeletal muscle. There are 100-400 molecule of myosin in each thick filament. Myosin is
a long asymmetrical molecule containing a globular head and two identical polypeptide
chains. Myofibrillar proteins are of special interest to the technologists because they
contribute to approximately 95% of the water holding capacity, 75% of the emulsifying
capacity and to a large extent the tenderness of meat.
Sarcoplasmic proteins:
These proteins make up about 30-35% of the total proteins in the skeletal muscle. Myoglobin is a
conjugated protein consisting of a prosthetic heme moiety and a protein moiety (globin). It provides
red colour to the muscle and serves as a carrier of oxygen to the muscle fibre. It is the most important
pigment of meat colour. Cytochrome enzyme, flavin etc. contribute very little to meat colour.
Stroma or connective tissue proteins:
The connective tissue is composed of an amorphous ground substance or matrix in which formed
elements mostly fibres and a few cells are embedded. The ground substance is a viscous glycoprotein
solution. The extracellular connective fibres are:
a. Collagen
b. Reticulin
c. Elastin
Collagen is the main fibrous protein the muscles and significantly influence the meat
toughness. It makes upto 40-60% of the total stroma protein and 20-25% of the total protein in the
body. High tensile strength and insoluble nature of mature collagen fibres is due to increased
inter-molecular linkages.
Reticulin is composed of small fibres which resemble that of collagen except for its intimate
association with a lipid containing myristic acid.

Elastin fibres are branched and do not hydrolyse on boiling. Elastin fibres are branched and do not
hydrolyse on boiling. Elastin contains two unique amino acids—desmosine and isodesmosine which
contribute to its highly insoluble nature. The nutritive value of elastin is practically nil due to its
resistance to digestive enzymes.
Content of water, protein, fat, ash(in percent) and calories
(approximate values for selected raw and processed food products)
Product Water Protein Fat Ash
Calories /
100g
F
R
E
S
H
Beef (lean) 75.0 22.3 1.8 1.2 116
Beef carcass 54.7 16.5 28.0 0.8 323
Pork (lean) 75.1 22.8 1.2 1.0 112
Pork carcass 41.1 11.2 47.0 0.6 472
Veal (lean) 76.4 21.3 0.8 1.2 98
Chicken 75.0 22.8 0.9 1.2 105
Venison (deer) 75.7 21.4 1.3 1.2 103
Beef fat (subcutaneous) 4.0 1.5 94.0 0.1 854
Pork fat (back fat) 7.7 2.9 88.7 0.7 812
P
R
O
C
E
S
S
E
D
Beef, lean, fried 58.4 30.4 9.2 213
Pork, lean, fried 59.0 27.0 13.0 233
Lamb, lean, fried 60.9 28.5 9.5 207
Veal, lean, fried 61.7 31.4 5.6 186
Raw-cooked sausage with coarse lean
particles (ham sausage)
68.5 16.4 11.1 170
Raw-cooked sausage finely comminuted, no
extender
57.4 13.3 22.8 3.7 277
Raw-cooked sausage
(frankfurter type)
63.0 14.0 19.8 0.3 240
Precooked-cooked sausage
(liver sausage)
45.8 12.1 38.1 395
Liver pate 53.9 16.2 25.6 1.8 307
Gelatinous meat mix (lean) 72.9 18.0 3.7 110
Raw-fermented sausage (Salami) 33.9 24.8 37.5 444
Milk (pasteurized) 87.6 3.2 3.5 63
Egg (boiled) 74.6 12.1 11.2 158
Bread (rye) 38.5 6.4 1.0 239
Potatoes (cooked) 78.0 1.9 0.1 72
Lipids
Lipid is a major component of the carcass of a meat animal. It is highly variable and is inversely
proportional to the moisture content.
Carbohydrates
Immediately after slaughter, muscle normally contains a very small amount (nearly 1%) of glycogen. It is a
macromolecule of glucose residues which serves as a reserve polysaccharide of animal tissue. However, it
gets worked up before the completion of rigor mortis and plays a key role in attaining the ultimate muscle

pH. Both the rate and amount of glycolysis influence the colour, tenderness and water holding capacity of
meat.
Minerals
About 3.5% of the total body weight is inorganic matter. Most of the total body inorganic material is located
in skeletal tissue primarily as salts of calcium and phosphorus and some other minerals especially
magnesium. In living meat animal, essential minerals like calcium, phosphorus, sodium, potassium, sulphur,
chlorine, magnesium, iron etc. and trace elements like manganese, copper, iodine, zinc, cobalt etc. Serve a
variety of important functions.
In the conversion of muscle to meat, inorganic elements play an important role. Their main function
relates to development of rigor mortis and alteration of fluid balance which cause a drop in pH and water
holding capacity. Inorganic constituents also influence the meat colour and tenderization. Several inorganic
ions act as catalysts during oxidation of meat fat, enhancing the process of rancidity development.
Vitamins
The vitamin content of meat is variable, depending on the species and age of the animal, the degree of
fatness and type of feed received by the animal. Water-soluble vitamins are localized in lean tissues whereas
fat-soluble vitamins in fatty tissues. Variety meats have substantial amounts of B-complex vitamins. Pork
contains 5-10 times more thiamine content as compared to mutton. The exudates from cut meat surfaces and
drip loss during thawing of frozen meat contain an appreciable amount of B-complex vitamins and amino
acids. Most of the vitamins in meat are relatively stable during processing or cooking. However, thiamine or
to some extent vitamin B6 are susceptible to heat treatment.
Slaughtering and Dressing of MeatAnimals
Slaughtering means pulling the food animals to death and thereafter preparing the carcasses for human
consumption. The essentials in the slaughter of food animals are that it should not cause unnecessary
suffering to the animals and bleeding should be as efficient as possible. Besides, it should be safe for the be
the handles also.
There are two main types of slaughter methods.
I. Scientific or Humane slaughter.
II. Ritual slaughter
Scientific or Humane Slaughter
Such a slaughter avoids unnecessary pain and cruelty to the food animal and ensures as complete bleeding as
possible. It is also ensure speed of operation and safety of the personnel.
Stunning is a process employed to create s state of immobility or unconsciousness at the time of slaughter to
1 minute. Immediately, the animal is hostel and bloods the animal to death. In USA and European countries,
stunning has been made mandatory by legislation in abattoirs, excepting those where ritual slaughter is
followed.
Stunning Techniques and Devices
They fall into three main categories
 Mechanical instruments: Instruments such as captive bolt pistol percussion stunner or free bullet
cause damage to the brain so the animal immediately losses the consciousness. In Brain, use of
captive bolt pistol is common for stunning cattle and sheep and several models of pistols are in
vogue. In captive bolt pistol an explosive cartridge, is used but in pneumatic stunner bolt is activated
under pressure to cause concussion without penetrating the frontal bone. Free bullet pistol may
become necessary for large bulls having very thick skull. The use captive bolt pistol differs with
species.
 Electrical stunning: It is conveniently employed in stunning of small ruminants, pigs and poultry.
The instruments either apparatus with a pair of tongs carries electrodes by which alternating current
(AC) is passed through brain. A high frequency current (250mA) of comparatively low voltage of
usually 75 volts is used for 10 seconds by way of application of electrodes or tongs at the base of the

ears on either side of the head. The electrodes are kept wet
in a 20% saline solution to enable the current to pass
easily through hair and skin. It produces instantaneous
unconsciousness for about 30 seconds.
If the current remains low missed shock may
occur resulting in paralysis of the animal.
 Chemical stunning: Carbon dioxide gas stunning is most
suitable for pigs and is f ollowed in many European
countries. Co2 is heavier than air and can be contained in
a tunnel. The gas blocks the nerve endings. Animal is
exposed to 65% carbon dioxide concentration through
oval type to 65% carbon dioxide concentration through
oval type tunnel, dip lift system or revolving wheel for 45
seconds. On exposure to gas, pigs become anaesthetized
that are then shacked and bled. Bleeding is quiet efficient
since carbon dioxide stimulates respiration favoring blood
circulation. However, it requires more space and is not
fast.
Sticking or Bleeding of the Animal- After stunning animal
lifted on the overhead rail, carotid arteries and jugular veins and
jugular veins of both the sides are cut across the throat region.
The yield of blood is as follows:
Buffaloes and cattle: 10-12 kg in 6 minutes
Sheep and goat; 1-1.5 kg in 5 minutes
Pig: 2.3 kg in 56 minutes.
Ritual Slaughter
Slaughter without prior stunning of food animals as per religious rites are referred -as ritual slaughter. There
are widely practical in many countries. In India and far East.
 Jewish method of Slaughter
or Schechita. The regulations
for Jewish slaughter came into
existence around 500 AD.
Consumption of pork was
strictly prohibited for Jews. In
Jewish method animals to be
slaughtered should be active.
The incision across the neck is
made by single rapid thrust of
sharp knife which severs the
skin, muscles, oesophagus
(भभभभ-भभभभभ), trachea,
carotid arteries and jugular
veins. This incision should be
completed without pause, pressure, stabbing or tearing. The blood vessels must be removed before
the retail sail of meat is undertaken. Kosher meat must be sold and consumed within three days of

slaughter. Jewish slaughter (Schechita) is undertaken by a Schochet (cutter) Carcass fit for Jewish
consumption is stamped with kosher seal on the brisket (भभभभभ भभ भभभभ).
 Muslim method of Slaughter or Halal- In this method, neck of the animal is served by cutting the
four major blood vessels-carotid arteries and jugular veins with a sharp knife. The spinal cord is left
intact. So the nerve centers controlling the heart and lungs remain functional and an efficient
bleeding is ensured. It also enhances the keeping quality of meat. Unlike Schechita, Muslim method
of slaughter is not controlled by a central board but it is overseen by the local Islamic authorities
(Musftis) Here, stunning may be permitted in some cases if it permits the heart to beat for some time.
Since animals have to struggle for sometime before in India, buffaloes and most of the sheep and
goat are slaughtered by Halal method.
 Jhatka or Sikh method of Slaughter In this method, the head of the animal is chopped off with one
big stroke of a sword. In some part of northern India, skilled workers can decapitate even buffaloes
by a single stroke of a special sword. In this process, bleeding remains incomplete. Due to presence
of some blood in tissues, the keeping quality of meat may be affected.
Ante-mortem Examination of MeatAnimals
Ante mortem Examination of meat animals awaiting slaughter is very necessary in order to produce to whole
some meat and thus safeguard the health of meat consumers. It should be conducted 12-24 hrs before
slaughter by qualified veterinarians. Hence, layout and construction of large should be such that it provides
proper light and provision of an isolation pen for diseased and injured animals. A number of para-veterinary
staff should also be at hand to help in the Examination. All animals meant for slaughter should be rested at
least for 24 hours and should not be fed for at least 12 hours before slaughter but they should be provided
with plenty of water.
Objectives
1. Detection of animals suffering from scheduled infectious diseases which are communicable to man.
2. To detect certain diseases which are toxic or contagious and whose identification is either difficult or
impossible during post mortem, e.g. tetanus, rabies, listeriosis, septic metritis, sturdy in sheep etc.
3. To prevent food poisoning out breaks e.g. in salmonellosis carcass or organs show little noticeable change
on post mortem
4. To make postmortem examination more efficient, accurate and less laborious.
5. To protect the health of butchers and slaughter house personnel.
6. To prevent unnecessary contamination of building and equipment of the abattoir.
7. To implement disease control programme with more precision by tracing back the source of disease.
Ante-mortem Examination procedure
It should be carried out in two stages
Stage I
General examination: Meat animals should be observed in the lairage pens during rest as well as in motion.
The general behaviour, reflexes, fatigue, excitement, gait, posture. Evidence of cruelty, level of nutrition,
symptoms of diseases, or any other abnormalities should be closely observed.
Stage II
Detailed examination: Suspected or diseased animals should be segregated for detailed examination. Their
temperature, pulse rate and respiration rate should be recorded. Animals showing elevated temperature and
systematic disturbance should be detailed for further inspection and treatment in the isolation pen

. Animal Temperature Pulse min Respiration min Gestation period
Sheep and Goat 39.5c 75 12.20 147 days
Pigs 39c 75 10.16 112 days
Cattle and Buffaloes 39c 50 12.16 280 days
Principles of judgement in Antemortem Examination
1. Fit for slaughter- Animals which are normal and free from any symptoms of disease should be sent for
sacrifice
2. Unfit for slaughter- highly emaciated, skin bound animals and those affected with tetanus or
communicable diseases like rabies etc. or diseases which can not be treated should be declared unfit for
slaughter.
3. Suspects- All suspected animals need further attention. Some animals with localized condition and
recovered cases should be passed for slaughter as suspect with instructions for careful postmortem
examination.
i. Detained animals some animals need to be detained for specified period of time for treatment of
disease or excretion of known toxic residence.
ii. Emergency slaughter It is recommended in cases where the animal is in acute pain or is suffering
from a condition where any delay in slaughter would be contrary to the welfare of animal. It is done under
strict supervision so that there is no hazard to the consumer health.
ANTEMORTEM INSPECTION
Some of the abnormalities which are checked on antemortem examination include:
1. Abnormalities in respiration
2. Abnormalities in behaviour
3. Abnormalities in gait
4. Abnormalities in posture
5. Abnormalities in structure and conformation
6. Abnormal discharges or protrusions from body openings
7. Abnormal colour
8. Abnormal odour
1 Abnormalities in respiration commonly refer to frequency of respiration. If the breathing
pattern is different from normal the animal should be segregated as a suspect.
2 Abnormalities in behaviour are manifested by one or more of the following signs:
The animal may be:
a. walking in circles or show an abnormal gait or posture
b. pushing its head against a wall
c. charging at various objects and acting aggressively
d. showing a dull and anxious expression in the eyes
3 An abnormal gait (pky) in an animal is associated with pain in the legs, chest or abdomen or is an
indication of nervous disease.
4 Abnormal posture (vklu) in an animal is observed as tucked up abdomen or the animal may stand
with an extended head and stretched out feet. The animal may also be laying and have its head turned along
its side. When it is unable to rise, it is often called a “downer”. Downer animals should be handled with
caution in order to prevent further suffering.
5 Abnormalities in structure (conformation) are manifested by:
a. swellings (abscesses) seen commonly in swine (lqvj)

b. enlarged joints
c. umbilical swelling (uky dh lqyu) (hernia)
d. enlarged sensitive udder indicative of mastitis
e. enlarged jaw
6 Abnormal colour such as black areas on horses and swine, red areas on light coloured skin
(inflammation), dark blue areas on the skin or udder (gangrene).
7 An abnormal odour is difficult to detect on routine A/M examination. The odour of an abscess, a
medicinal odour, stinkweed odour or an acetone odour of ketosis may be observed.
Examination of a carcass should be carried out as soon as possible after the completion of dressing in order
to detect any abnormalities so that meat animals awaiting slaughter is very necessary in order to produce to
whole some meat and thus safeguard the health of meat consumers. It should be conducted 12-24 hrs before
slaughter by qualified veterinarians in fairage pens. Hence, layout and construction of large should be such
that it provides proper light and provision of an isolation pen for diseased and injured animals. It should be
ensured that animals are not subjected to any kind of cruelty. A number of para-veterinary staff should also
be at hand to help in the Examination. All animals meant for slaughter should be rested at least for 24 hours
and should not be fed for at least 12 hours before slaughter but they should be provided with plenty of water.
Objectives
1. Detection of animals suffering from scheduled infectious diseases which are communicable to man.
2. To detect certain diseases which are toxic or contagious and whose identification is either difficult or
impossible during post mortem, e.g. tetanus, rabies, farcy, listeriosis, septic metritis, sturdy in sheep etc.
3. To prevent food poisoning out breaks e.g. in salmonellosis carcass or organs show little noticeable change
on post mortem
4. To make postmortem examination more efficient, accurate and less laborious.
5. To protect the health of butchers and slaughter house personnel.
6. To prevent unnecessary contamination of building and equipment of the abattoir.
7. To implement disease control programme with more precision by tracing back the source of disease.
Ante-mortem Examination procedure
It should be carried out in two stages
Stage I
General examination: Meat animals should be observed in the lairage pens during rest as well as in motion.
The general behaviour, reflexes, fatigue, excitement, gait, posture. Evidence of cruelty, level of nutrition,
symptoms of diseases, or any other abnormalities should be closely observed.
Stage II
Detailed examination: Suspected or diseased animals should be segregated for detailed examination. Their
temperature, pulse rate and respiration rate should be recorded. Animals showing elevated temperature and
systematic disturbance should be detailed for further inspection and treatment in the isolation pen.
Animal Temperature Pulse min Respiration min Gestation period
Sheep and Goat 39.5c 75 12.20 147 days
Pigs 39c 75 10.16 112 days
Cattle and
Buffaloes
39c 50 12.16 280 days

Principles of judgments in Antemortem Examination
1. Fit for slaughter- Animals which are normal and free from any symptoms of disease should be sent for
sacrifice
2. Unfit for slaughter- highly emaciated, skin bound animals and those affected with tetanus or
communicable diseases like rabies etc. or diseases which can not be treated should be declared unfit for
slaughter.
3. Suspects- All suspected animals need further attention. Some animals with localized condition and
recovered cases should be passed for slaughter as suspect with instructions for careful postmortem
examination.
i. Detained animals Some animals need to be detained for specified period of time for treatment of disease or
excretion of known toxic residence.
ii. Emergency slaughter It is recommended in cases where the animal is in acute pain or is suffering from a
condition where any delay in slaughter would be contrary to the welfare of animal. It is done under strict
supervision so that there is no hazard to the consumer health.
Antemortem examination of meat animal is of prime importance from public health point of view. It is the
initial step in detection of any sign of disease, distress, injury etc. which helps in taking appropriate decision
before slaughter of animal. It should be done properly and systematically by qualified and experienced
veterinarian who will in turn help in maintaining high standards of meat quality.
Postmortem Inspection of Meat Carcasses
Many diseases and abnormal conditions not detectable on Antemortem necessitate a careful
postmortem inspection. It should be conducted as soon as possible after carcass dressing is complete, as
setting of carcass may render it difficult to expose and examine the lymph nodes afterwards. It has to be
carried out in a hygienic manner avoiding unnecessary cuts. It will involve palpation of organs and tissues,
incisions where necessary and laboratory tests in certain conditions. All these aspects ate taken into
consideration before passing the final judgment.
Objectives
i. To detect and eliminate abnormalities from the carcass and organs including contamination, thus ensuring
that only meat fit for human consumption is passed for food.
ii. To check the efficiency of slaughter and carcass dressing.
iii. To diagnose disease conditions for control purpose.
iv. To ensure that carcasses, parts or organs marked unfit for human consumption are property disposed of or
destroyed.
Facilities
1. The area where the examination is being conducted should have sufficient and well distributed light.
The natural light is considered better than artificial light.
2. The person carrying inspection need clean, sharp, stainless knives. There must be provision for hot
and cold water.
3. There should be a sterilizer (operates at temperature of 82degree C) to sterilize the knives, saws and
cleavers. The knives should be sterilized either by dipping them in boiling water for 30 minutes or by
heating them for 10- 15 minutes in oil, liquid petroleum jelly or glycerin at a temperature of 248°F to
266°F.
4. To put a mark on carcass and its viscera, marking dyes should also be provided, which should be
cheap, non-toxic and noncorrosive in nature.

5. Marking of meat is done by (i) using a stamp (ii) branding (iii) labeling. Common method - Metal
stamp dipped in a stamping ink.
6. There should be provision of
detained room side by the
inspection site.
General principles
Postmortem inspection involves visual
perception and palpation of organs and
tissues, incisions where necessary and
laboratory tests wherever confirmation
is required. It should always proceed in
a systematic and hygienic manner.
Examination of lymphnodes is of
paramount importance in postmortem
inspection,
A swelling or enlargement or
discolouration of a lymph node indicates s a pathological condition.
1. Visual perception: First the carcass and visceral organs should be examined visually for any visible
abnormalities. Examination is done for any change of colour, hypertrophy (the enlargement of an
organ or tissue from the increase in size of its cells), etc.
2. Palpation: The organs are palpated for any change in consistency, sliminess or gelation, cyst etc.
3. Incisions: The organs are incised, if needed. This is done to examine any parasite inside organ,
structural deformity etc.
4. Laboratory tests: These are done for confirmation and support the observation made by
macroscopic examination. While examining the organs of carcass, lymph node of adjoining area
must be examined.
Based on the postmortem examination, meat inspector can given any of the four judgments’.
a. Passed.
b. Total contamination
c. Partial contamination
d. Conditionally passed.
Procedure
In general, postmortem inspection of buffalo and swine carcasses should proceed in the following order.
Head-An examination of surface of tongue is done for FMD (Foot and Mouth Disease) and other form of
stomatitis (मुखशोथ) Palpation of tongue from dorsum to lip is carried out to detect actinobacillosis
(Actinobacillosis is a zoonotic disease caused by Actinobacillus. The most prominent symptom is the
swelling of the tongue that comes out of the mouth and is very hard at palpation (wooden tongue).
Viscera-All viscera should be inspected as they are removed from the carcass. Every organ and associated
lymph nodes are examined. In case of any abnormal condition, the organs are incised not to contaminate
other organs or carcass parts.
Lungs: Visual inspection followed by palpation (टटोलने का कार्य) is carried out for evidence of pneumonia,
tuberculosis, etc

Heart: pericardium is opened and looked for
tuberculosis pericarditis. Heart is incised to
detect cysts (alsar).
Liver: The surface and substance of liver is
examined for fatty changes, actinobacillosis,
and parasitic infections like Cysticercus bovis
Kidney: Renal (गुर्दे gurde) lymph nodes and
adrenal glands should be anthrax,
tuberculosis.
Stomach and intestine: The serous surface of these organs could indicate tuberculosis or actionbacillosis
while interior part reticulum could show penetration of foreign body. Mesenteric lymph node is incised as a
routine to look for tuberculosis.
Urinary bladder: The outer and inner surfaces of urinary bladder are observed for diseased condition.
Uterus and ovaries: These are opened for examination of septic conditions.
Udder: This is examined for septic mastitis or
abscesses are incised for evidence of abscesses or
tuberculosis.
Carcass The carcass should be inspected for evidence
of discoloration. Age of bruise can be determined by
using bilirubbin test. Diaphragm should be lifted and
examined carefully for tuberculosis. After the carcass
is spilt, cut surfaces of sternum (breast Bone), ribs,
vertebrate (Having a backbone or spinal column) and
spinal cord should be examined.
Postmortem Inspection of Sheep and Goat
Carcasses
The Examination is carried out on the above lines.
However, Sheep and goat do not require much detailed
examination. Carcass is, therefore, examined for
satisfactory bleeding, liver for fascioliasis and lungs for parasitic infections..
Post mortem inspection of Swine Carcass (Some Specific precautions)
Although PM examination follows as the same pattern as in buffalo/ cattle, skin lesions serve as important
diagnostic feature of swine fever. Visceral organs should be examined for pneumonia and also sub maxillary
lymph nodes for tuberculosis.
Key Words
 A zoonotic disease is a disease that can be passed between animals and humans. Zoonotic diseases can be
caused by viruses, bacteria, parasites, and fungi. These diseases are very common. Scientists estimate that
more than 6 out of every 10 infectious diseases in humans are spread from animals.
 The adrenal glands (also known as suprarenal glands) are endocrine glands that produce a variety
of hormones including adrenaline and the steroids aldosterone and cortisol.
 In cattle Cysticercus ovis appears as small whitish cysts filled with fluid that contains an immature
worm. They have the size of a pea 5 to 8 mm.

 A swollen area within body tissue, containing an accumulation of pus: once the abscesses burst, they
usually discharge for several days before gradually healing u.
 The bilirubin blood test measures the level of bilirubin in the blood. Bilirubin is a yellowish pigment
found in bile, a fluid made by the liver. Bilirubin can also be measured with a urine test.
 Bile is a bitter greenish-brown alkaline fluid which aids digestion and is secreted by the liver and
stored in the gall bladder
 Lymph nodes are located throughout the body but the largest groupings are found in the neck,
armpits (a hollow under the arm at the shoulder.), and groin areas. Swollen lymph nodes may be a
sign that the body is dealing with an infection, injury, or cancer.
 the groin (the adjective is inguinal, as in inguinal canal) is the junctional area (also known as the
inguinal region) between the abdomen and the thighbone either side of the pubic bone.
 Fasciolosis is a parasitic worm infection caused by the common liver fluke Fasciola hepatica as well
as by Fasciola gigantica.
Basic Processing Procedures:
1. Comminution: All processed meats can be classified as either non-comminuted or comminuted
products. Non-comminuted products are generally processed from intact cuts. These products are
usually cured, smoked and cooked, e.g. ham and bacon. Comminution refers to subdivision or
reduction of raw meat into meat pieces or particles. The degree of comminution or particle size
varies with the processing characteristics of products. Such meat particle size reduction helps in the
uniform distribution of seasonings and eliminates the toughness associated with meat of old animals
and lowers the fuel cost for cooking. Comminution is done with the help of meat mincer for coarse
ground products whereas bowl chopper is also employed for making fine meat emulsion.
2. Emulsification A mixture of two immiscible liquids where one liquid is dispersed as droplets in
another liquid is called emulsion. An emulsion has two phases—a continuous phase and a dispersed
or discontinuous phase. These phases remain immiscible due to the existence of an interfacial tension
between them. The emulsion remains unstable if interfacial tension is very high. The emulsion can be
stabilized by reducing the interfacial tension with the help of emulsifying agents or emulsifiers.
Homogenized milk is a good example of true emulsion in which fat droplets are dispersed in an
aqueous continuous phase. The size or diameter of dispersed fat droplets in a true emulsion ranges
from 1 to 5 micrometer (μm).
3. Pre-blending: It refers to the mixing of a part or all the curing ingredients (salt, nitrite, nitrate etc)
with ground meat in a specified proportion. This process allows better extraction of proteins which in
turn helps in the formation of stable emulsion. It permits control of product composition by adjusting
the desired fat content. Besides, processors get enough time for the analysis of meat samples
SlaughterHouses or Abattoir
Slaughter houses or abattoir means any premises that is approved and registered by the controlling authority
in which animals are slaughtered and dressed for human consumption. Abattoir may be small, medium or
large based on the number of animals slaughtered. Based on the level of technology adopted the operations
are manual, semi-mechanized or fully automatic. The slaughter houses play an important role in the

processing of animals for production of safe and wholesome meat and in the effective recovery of by-
products. The important sections of the modern abattoir are
(a) Lairage for resting the animals prior to slaughter;
(b) Slaughter hall;
(c) By-product room;
(d) Meat cutting room (optional);
(e) Rendering room (optional) or simple system of treating offal’s or condemned carcass.
The building should be furnished with fly- proof system, sufficient lighting, ventilation and water
supply. Let us appreciate that application of modern scientific methods for processing of meat in abattoirs
would provide safety, value addition, and convenience and consumer satisfaction.
The Govt. of India has initiated a number of programmers’ for improvement and modernization of
slaughter production. Towards this end, we as trained technicians should ensure for humane methods of
slaughter and production of meat under hygienic conditions. Slaughtering of animals in unconscious state
will facilitate prevention of cruelty. The essential processing steps in abattoir are:
(i) resting animals in lairage prior to slaughter;
(ii) ante-mortem inspection;
(iii) stunning (depends on religious customs);
(iv)slaughter and bleeding on the cradles;
(v) skinning, dressing and evisceration on the overhead rail;
(vi) post – mortem inspection;
(vii) washing;
(viii) Holding the carcass in chill room (optional); ix) cutting and packing (optional).
Curing
Cured and smoked products are popular and comprise large volume of total processed meats in the
developed countries. Curing and smoking are generally done to preserve the meat products and to develop
desired colour, flavour and texture of the meat products. Curing of meat was originally developed in ancient
times for preservation of meat by addition of table salt. Modem meat curing employs use of many other
chemicals/additives to produce characteristic flavour and colour. Example of cured and smoked meat
products are ham, bacon, corned beef.
Advantages of Curing
 Curing improves keeping quality by inhibiting growth of spoilage bacteria.
 It produces characteristic pink colour.
 It provides salty flavour, which is liked by most of the consumers.
 It improves tenderness and juiciness.
 It improves functional properties.
 Curing ensures microbiological safety of the product by preventing food poisoning due to
Clostridium botulinum.
 Larger meat cuts can be cooked or smoked directly after curing.
 Nitrite reduces rancidity in cured meats.
Curing agents
a) Salt (Sodium chloride): Salt is the most important curing ingredient. The generally used salt level in
most of the meat products is between 1.5 and 2 per cent. In fermented and cured meat products
higher level of salt are used e.g. 3 to 4 per cent in fermented sausages, 2 to 3 per cent in brine cured
hams, 5 to 8 per cent in dry cured hams.

b) Sodium nitrate/nitrite (NaNO3/NO,): Sodium nitrate or sodium nitrites are essential components of
curing mixture. When sodium nitrate is used, it is converted into nitrite by microbes or by reducing
agents such as ascorbate. Sodium nitrite can also be used directly in the curing mixture. It is
responsible for the colour fixation of meat pigments and this result in characteristic cured pink
colour. The maximum permitted level of nitrate or nitrite or combination of both for most of the meat
products is 120 to 200 ppm (120 ppm in bacon and 200 ppm in hams). The limits have-been
prescribed because during smoking or frying excess nitrite gets converted into nitrosamines that are
carcinogenic in nature.
c) Sugar: It is also an important curing ingredient. It provides substrate for the formation of acid and
thus, lowers the pH of cure. The most frequently used sugars in meat curing are sucrose, dextrose and
cane sugar. Maximum permissible limit for sugar in the final product is two per cent.
d) Sodium ascorbate and erythorbate: Use of ascorbate (commonly known as Vitamin C) and
erythorbate has been proved very useful in the curing. These substances accelerate curing process
specially colour development. These prevent fading of cured colour of meat. The residual ascorbic
acid. Ascorbate also inhibits the formation of nitrosamines (carcinogenic substances) in cured meats.
Generally, upto 550 ppm of sodium ascorbate is used for curing of meat products.
e) Phosphates: Alkaline phosphates improve the water binding quality of meat and thus improve the
final yield of products. As much as 10 per cent improvements in cooking yield can be achieved by
use of phosphates. Different types of phosphates are approved e.g., sodium tripolyphosphate, sodium
pyrophosphate, di-sodium phosphate etc. Final product should not contain more than 0.5 percent of
phosphates.
f) Monosodium glutamate: It is a flavour enhancer and used as a component of curing solution to
improve the flavour of meat products. It helps in reducing the product cost by improving the
moisture percentage in the end product.
Methods of Curing
There are several methods to infuse cure ingredients into meat tissue. We can apply dry cure mixture directly
or after dissolving ingredients in water. The distribution of ingredients into meat tissue can also be facilitated
by use of machines. Different methods used for curing are:
 Dry curing
 Pickle curing
1 Dry curing: Dry curing is a traditional method. In this method, dry ingredients are rubbed over the external
surface of meat. This is a slow method. Completion of curing may take months. In dry salt curing, common
salt along with nitrite or nitrate is used.
Dry curing of hams usually consists of three stages:
a) Dry cure mix is applied on the muscle surface of hams and hams are kept for 2 to 3 weeks at around
5°C.
b) After 2 to 3 weeks of curing, excess cure mixture is washed from the surface. Hams are hanged for 2
to 4 weeks at 10 to 16OC and relative humidity between 55 and 70 per cent. This is called
equalization period.
c) In next stage, hams are placed in a chamber maintained at temperature of 25 to 30°C and relative
humidity of 55 to 70 per cent for 3 weeks or more. This is called aging period.
Advantages
 Dry curing results in very good flavour and texture.
 No special curing equipment is required.
 Dry cured products have very long shelf life.

Disadvantages
 Complete cure penetration may require 35 to 45 days for hams and 8 to 14 days for bacon.
 Rancidity may also developed during curing
 Storage cost during cuing is high.
 Yield of final product is low.
 High salt concentration in product is not good from health point of view.
2 Pickle curing: In this type of curing, water is used as a medium for dissolving the curing ingredients and
the product is placed in a vat containing brine solution (solution containing cure ingredients). The curing
process is accomplished by diffusion of brine into the tissue at refrigerated temperature. Curing process
completes within 2 to 3 days.
Advantages
 This method results in more uniform distribution of cure throughout the product as compared to dry
curing.
 This method is faster.
 Final yield of the product is higher than dry curing because some water is also absorbed into the
product.
Disadvantages
 If refrigerated temperature is not maintained or contaminated curing solution is used, then spoilage of
meat (especially near bones) can occur.
 Solution becomes ropy during storage and thus, imparts off flavour to the product.
Injection curing is one type of pickle curing. In this method, brine is injected directly into the meat chunks.
This reduces the risk of spoilage. Also less curing time is required.
Advantages
 Injection curing ensures rapid penetration of curing ingredients.
 Incidences of spoilage are greatly reduced.
Disadvantages
 Rapid curing may not result into development of the characteristic flavour and texture.
 There are chances of tissue disruption and formation of pickle pockets in the tissue.
Generally three methods are used for injecting brine.
(a) Artery pumping: Curing solution is injected into the ham through femoral artery.
(b) Single-needle Stitch pumping (Pump pickling): The curing solution is injected under pressure into the
meat with the help of brine pump.
(c) Machine pumping (Multiple-needle Stitch pumping): Under commercial processing, curing solution is
injected with the help of multiple needle machine called 'cure injector'
3 Combination curing: This is a quick method of curing. In this method, both dry and injection curing or
injection and immersion curing is done. Under commercial practice, injection curing combined with
mechanical agitator like tumbler or massager is preferred. Thus, the combination curing can be of following
types:
Injection followed with liquid curing
Injection combined with dry curing
Injection with mechanical agitation
SMOKING
Smoking is generally practiced along with curing. Smoke obtained by the slow combustion of hardwood saw
dust contains lower alcohols, aldehydes, organic acids; carbonyl compounds, phenols etc. preserve meat by

its bacteriostatic, bactericidal and antioxidant properties besides providing a protective film on the surface.
Smoke also imparts characteristic flavor and stabilizes the cured colour. The temperature of smoke chamber
is maintained at 500C to produce ready-to-cook chicken whereas it is kept at 800C for 4 hours at 30-35 per
cent relative humidity to produce ready –to-eat chicken. In order to eliminate the carcinogenic components
due to combustion of lignin especially benzopyrene, liquid smoke is produced these days through
condensation. Liquid smoke can be directly sprayed over the cured chicken or added to meat emulsion to
impart distinct flavor. Cured and smoked chicken has a shelf life of month under refrigeration (40C) and 2 to
4 ,months in a freeze (-180C).
Advantages of Smoking
1. Smoking of meat and meat products provides characteristics flavour and colour to the cured
products.
2. Smoke has antimicrobial properties and inhibits microbial growth.
3. Smoke has antioxidant properties and retards oxidation of fat.
4. Smoking of meat cause surface dehydration.
Thus the preservative effect of smoke is due to surface drying (reduced moisture content), antimicrobial and
antioxidant properties.
Composition of Smoke
Smoke is generated through combustion of saw dust at about 300°C. Generally hard wood saw dust is used.
Smoke contains more than 200 components. These are derived from different components of wood i-e.,
cellulose, hemicelluloses and lignin. The major components of smoke are given bellow:
 Phenols
Act as antioxidant,
Have Bacteriostatic effect,
 Aldehydes
Contribute to color
 Alcohols
 Organic Acids
 Hydrocarbons
 Carbonyls
Gases such as carbon dioxide, carbon monoxide, oxygen, nitrous oxide etc contribute to formation of
undesirable compounds such as nitrosamines and also contribute to colour.
Methods of Smoking
Dry smoking
Traditionally fire pits or cabins were used for smoking of meat. Now-a-days automatically controlled
chambers called Smoking ovens are used for smoking. The meat products are placed in the sealed smoking
chamber of the oven. Smoke is generated outside of this chamber by controlled combustion of moist sawdust
and allowed to go inside the chamber. Meat products are smoked continuously for many hours. Control of
temperature, air velocity, smoke density and relative humidity inside the chamber are very important for
quality of smoked products.
Smoking of meat products generally consists of following stages:
 Drying: Optimum moisture is required for penetration of smoke into the product. So before starting
smoking, product is slightly dried to reduce surface moisture to the desired level. This stage may take
30 minutes to 1 hour.
 Smoking: Meat products are generally exposed to smoke for 4-24 hours. The temperature and the
relative humidity are adjusted depending upon the type of product.
 Cooking: After smoking, the temperature is raised to cook the product. Generally, internal
temperature of product is taken into consideration during cooking.

 Showering and chilling: Immediately after cooking, the products are showered or washed to remove
external salt and fat steaks. After washing, products are cooled to 50C, sliced and packaged.
In computer based smoke ovens, all factors affecting amount and rate of smoke deposition and quality of
product can be controlled. These include smoke velocity, relative humidity, smoke density, temperature
etc. For control of relative humidity, moisture in the form of humidity is added in the smoking chamber.
Liquid Smoking
Liquid smoking is another method of smoking of the product. This method is followed in the developed
countries. Liquid smoke is prepared by passing smoke through liquids i.e. smoke is- in water. During
preparation carcinogenic compounds are filtered. Meat pieces are either sprayed with or dipped in liquid
smoke. Sometimes liquid smoke is added directly in the ground meat formulation to provide characteristics
smoked flavour.
Advantages of Liquid smoking
 Less time is required in the preparation of the product
 It does not contain any carcinogenic or harmful substances
 Minimum variation occur in the different batches
 It is easy to apply
Sausages
Sausage term was derived in the ancient times from the latin word ‘salsus’ meaning salt. It was literally
coined to refer to ground meat which was salted and stuffed in animal casings. Presently, sausage may be
defined as a meat product which is prepared from minced and seasoned meat and formed into cylindrical
shape by natural or synthetic casings. Though sausages originated in the western world, these products
acquired universal popularity due to variety and convenience to the consumers. Sausages are economical
also because these are generally prepared from cheaper cuts of meat and by-products of industry.
Classification
Sausages are such a large number of varying kinds of products that it is not possible to cover them in any
classification system. Some overlapping is always there. Some of the popular classification systems are:
i. Based on degree of chopping: a. Coarse ground sausage
b. Emulsion type sausage
ii. Based on moisture content: a. Fresh sausage
b. Smoked uncooked sausage
c. Cooked sausage
d. Dry and semi-dry sausage
iii. Based on fermentation: a. Fermented sausage
b. Non-fermented sausage
Processing Steps
1. Grinding or mincing Lean meat and fat are minced separately in a meat mincer. The choice of
mincer plate or sieve depends on the type of meat.
2. Mixing Meat and fat to be used for the preparation of coarse ground sausage are mixed uniformly in
a mixer. Extender, condiments and spices should also be run in the mixer for even distribution.
3. Chopping and emulsifying For emulsion preparation, lean meat is first chopped for few minutes in
a bowl chopper with salt to extract myofibrillar proteins. This is followed by addition of fat and
running for a few minutes again to get desired emulsion consistency. Now, all other ingredients are
added and chopper is run for some time for uniform distribution. The entire operation is conducted at
low temperature by addition of ice flakes in place of chilled water.

4. Stuffing Sausage emulsion or batter is taken to stuffer for extrusion into casings. The casings are
first collected on the stuffing horn or nozzle and released to coincide with the extrusion.
5. Linking and tying In small sausages, the encased mass is twisted to produce links either manually or
mechanically whereas in large sausages, the encased mass is tied with thread at regular intervals.
6. Smoking and cooking Sausage links are hung on the smokehouse trolley and transferred to smoke
house. The temperature of smokehouse is usually maintained at 68-700C which is enough for
coagulation of sausage emulsion, cooking and requisite drying of sausages.
7. Chilling The cooked product is showered with chilled water to an internal temperature of about 40C.
8. Peeling and packaging While artificial or synthetic casings are peeled off before the product is
packed, small sized natural casings need not be removed. The product is generally unit packed for
retail outlets.
MeatPickles
Meat pickles are ready to eat, highly acceptable convenience meat products of indigenous origin. Pickling of
meat by use of edible organic acids mainly vinegar and or edible oil, table salt, sugar, spices and condiments
imparts special flavour and shelf-stability to the product.
Processing
Meat pieces of about 2-3 cm3 are pressure cooked for about 5 minutes. Cooked chunks are deep fat fried in
mustard oil till it develops slight golden brown colour and taken out. The fried meat chunks are kept
separately till further use. The green curry stuff (onion, garlic and ginger in the ratio of 3: 1: 1) and dry spice
mix are fried in the same oil and meat broth is added and heated with constant stirring till boiling. Fried meat
chunks are added and boiled for another 2 to 5 minutes. Then the flame is put off and allowed to cool to
room temperature. Finally acetic acid is added and mixed thoroughly. Then pickle is allowed to cool of its
own for packing. For better keeping quality, heated and cooled mustard oil may be over layed on the pickle
in the bottle/ packet. Processing of different types of meat pickles viz. pork pickle, chevon pickle, chicken
pickle, gizzard pickle etc. have been reported.
Meat pickle recipe chunked and canned
Ingredients Quantity
Meat chunks (Bones in or boneless) 1000 g
Dry spice mix (4%), 40g
Green condiments (10%) 100g
Meat broth 200ml
Mustard oil 200ml
Acetic acid (1%) 10ml
Salt - (4%) 40g
Flow diagram of meat pickle preparation:
1. Meat cuts
2. Deboning,fattrimmingandcuttingof meatintosmall pieces
3. Pressure cookingforabout5 minutes(separationof meatchunksand broth)
4. Deepfatfryingof cookedmeatin oil (separationof friedchunksandoil)
5. Fryingof greencurry stuff anddry spice mix inoil
6. Additionof meatbrothandheatingwithconstantstirringtill boiling
7. Addition of friedmeatchunksandboilingforanother2to 5 minutes
8. Coolingtoroom temperature
9. Additionof aceticacidand thoroughmixing

Canned meat
Canning is the preservation of meat by heat processing in a container. Carefully selected and
prepared food sealed in container is subjected to heating for a definite time. Thus, in canning, heat (steam) is
applied to sterilize the product placed in a sterilized container (can) for the production of safe products of
desirable flavour, texture and appearance and for long storage life of the product. Beef, ham, sausages and
luncheon meat are being canned. Here, heat destroys microorganisms and sealing prevents the
recontamination of food by microorganism.
Generally, a temperature above 100°C is used for processing of the canned meats. They are,
therefore, regarded as commercially sterilized meat products. The process to which they are subjected is
called sterilization. This process kills all potential spoilage organisms. The thermal processing to achieve
sterility is usually done in large metal drums known as "retorts" which are capable of withstanding pressure
up to 32kg / cm2.
Types of cans: Cans used for meat products are generally made up of low carbon steel or aluminum. The
inner side of these cans is coated with tin or chrome. The cans are classified generally based on their shape
e.g. square, pear shape, round or oblong.
Round Sanitary Pear Shaped
Drawn Aluminum Oblong
Canning Process
Meat canning involves many steps, although the basic principle is heat treatment of a sealed container.
These steps are described below:
 Preparation and can filling- In meat foods a firm dry product is required. Therefore, meats are pan
boiled. Inedible parts like bones, cartilages and tendons and excess fat are removed. Then the
processed meat is placed in cans. When solid food is canned with liquid material, solid must be filled
first followed by liquid. Care must be taken to avoid air trapping during filling of the product. Head
space in the can must be taken into consideration as efficiency of the exhaustion depends largely on
the headspace volume. Atleast l /8th of the can's height should be left empty as headspace.
 Exhausting and sealing-After filling the cans are exhausted before sealing. Exhausting is the
removal of the air from the container. During heating, expansion of contents may cause leaks in the
can which can be prevented by exhausting.

Advantages of exhaustion are as follows:
 It reduces the risk of causing a rise in the internal pressure during heat treatment resulting in
can blowing or deformation.
 It lowers the amount of oxygen to prevent discolouration of meat surface.
 It helps in reducing chemical reaction between food products and container.
 It creates an anaerobic condition inside the can and thus prevents the growth of aerobic
organism.
Exhausting is done either by heating or vacuum. During heating the air in the can is replaced by
water vapour and when the can is cooled down, vacuum is created by the condensation of the water vapour.
Then the can is sealed hermetically and sealing is done by a double seamer machine. Alternatively, the cans
are conveyed on a belt into an exhausting chamber or tunnel where almost 90% of the air is removed from
the can and sealed simultaneously.
 Thermal processing-After sealing the cans are subjected to cooking either by low temperature i.e.
6570°C or high temperature i.e. >100°C. In commercial sterilization, the products are heated to
internal temperature of 121°C. After commercial sterilization, products can be stored at room
temperature. But, treatment at this temperature may affect flavour, texture and colour of the products.
In pasteurization, the products are heated to an internal temperature of 65 to 75°C. At this
temperature, product qualities are not affected. After this treatment, cans are stored at refrigerated
temperature till consumption. The products should be pasteurized or sterilized for sufficient time.
 Cooling-After thermal processing the cans should be cooled as quickly as possible to prevent undue
changes in texture and colour of the product. The inner temperature of the cooled product should not
exceed 38°C. It is better to permit some heat to remain in the can to evaporate the water on the
surface of the can. Otherwise, wet can may be rusted and may create problem in labeling. During
cooling cans are subjected to internal pressure change and may be deformed. Thus the cans should be
cooled under pressure to prevent the deformation of the can end. Always chlorinated water should be
used for cooling to maintain the microbiological quality of the product. under pressure to prevent the
deformation of the can end. Always chlorinated water should be used for cooling to maintain the
microbiological quality of the product.
 Can washing-The cans may be dirty and greasy after cooling. Thus the cans are washed thoroughly
with potable cold water to remove dust and grease. For washing soap may be used. This will help in
subsequent handling, labeling and lacquering.
 Outside lacquering and labeling-A coloured varnish containing vegetable resin or synthetic resin is
applied outside to prevent rusting of cans especially when the cans are transported through moist
area. Labeling is done to provide information about the product regarding ingredients used,
manufacture date, expiry date, batch number, consumer's instruction etc. The durability of canned
meat lasts for atleast two years. Cans should be stored in a cool and dry place (at a temperature of
about 20°C). The quality of the product is favourably compared to cooked meat. There are many
canned meat products like corned beef, luncheon meat, meat ball with gravy, beef stew, potted meat
etc. Only the processing of first two products is described here.

Popular canned meat product
Corned beef: This is a semisolid product containing meat (beef), potatoes, curing agents, seasoning etc.
Corned beef refers to the preservation by the use of salt. The term corned applied to meat processed by
salting. The weight of the cooked meat should be less than 70% of the weight of the uncooked fresh meat.
The processing steps are as follows:
Chilled meat
Grinding through 2 inches plate
Cooking for 10-201minutes at 180°F
Cooling and grinding through 3/16inches plate
Separation of broth
Mixing of potatoes, blanched onion, salt, sodium nitrite and other ingredients with precooked ground meat
Filling into can (Ground meat and broth)
Exhausting and closing of the can
Heating at 240°F for 75 minutes or at 250°F for 55 minutes.
Cooling to 95-105°F
Spoilage of Canned Meat Products
There may be following microbial or chemical spoilage.
I. Hydrogen swell: Any scratch on the inner tin coating exposes the iron of the can. Acidic food reacts
with this iron and produces hydrogen gas. This ultimately leads to bulging of the can.
II. Flat souring: This condition is seen in the meat products which contain cereal and other seasonings.
This is caused by thermophilic organisms which produce acid in the product and ultimately leads to
souring without formation of any gas.
III. Purple staining: At high temperature processing thermophilic organisms may attack sulphur
containing proteins and produce hydrogen sulphide. This reacts with tin of the can and produces tin
sulphide. This leads to blackening of the inner side of the can. When hydrogen sulphide reacts with
iron of the can, it produces iron sulphide which imparts purple colour to the product. If sulphur
resistant lacquer is applied then this condition can be prevented.
Spoiled cans may show following abnormalities:
(i) Swell or blower: When the ends of the can are bulged by positive internal pressure due to gas
produced by microbial or chemical activity, the can is called as swell or blower.
(ii) Springer: A springer can have one end bulged but that end can be forced back into the normal
position whereupon other end bulges.
(iii) Flipper: A flipper can is apparently normal but if the can is struck against a solid object then one
end flips out and again it comes to normal after applying a light pressure.

(iv) Leaker: If there is any hole in a can through which air or infection may enter into the can or can
contents escape, then this is a leaker can.
KEY WORDS
 Preservation: Aims to inhibit microbial spoilage and arrest physio-chemical changes which bring
about deterioration in quality.
 Lactose: A type of natural disaccharide consisting of glucose glactose present in milk.
 Pasteurization : A process of heating every particle of milk or milk product to specified temperature
and holding at that temperature for specified period followed by immediate cooling and storage at
low temperature.
 Hatching: Production of baby chicks from fertile egg.
 Abattoir : Premises that is approved and registered by the controlling authority in which animals are
slaughtered and dressed for human consumption
 Comminution: It refers to subdivision or reduction of raw meat into meat pieces or particles.
 Post-mortem: It is the systematic exposure and scientific examination of the tissue and organ of a
dead body to determine the cause of death, the nature of lesions and illness.
 Aquaculture: The term relates to the culture of fish in fresh water, backlash water and sea water.
 Spawning: The process of releasing eggs by female and wilt by male is called spawning.

Inspection of poultry birds, dressing and preparation of ready to cook poultry,
factors affecting the quality
Several poultry dressing plants have come up in the country and many more are in the offing where large
number of birds are to be handled and processed every day. These birds should be handled properly before
slaughter. It reduces the changes of bruises, cuts and tears on the dressed birds. In fact, pre-slaughter care
contributes a good deal to the wholesomeness of dressed chickens.
Pre-slaughter Care and Handling
In the intensive housing system, a great care has to be exercised in catching and crating the birds. The
broilers are generally caught at night under very dim light. Culled and spent hens are caught in the cooler
hours of the day, preferably in the afternoon. The birds are caught manually.
Creates, coops or cages are used to transport birds in vans from the farm to poultry dressing plant.
During transportation special attention is paid to prevent overcrowding and suffocation. The loading of birds
is carried out in dim light either early morning or late evening to avoid excitement and transported in the
cool period without much exposure to sun to prevent excessive shrinkage. Birds should be kept off feed for
12 hrs before slaughter but enough shrinkage water should be made available. This practice not only helps in
early evisceration but risk of contamination of meat by the intestinal contents is also minimized.
According to federal inspection acts, poultry arriving at a processing plant are inspected many times before
slaughtering. The inspector observes the birds in the coop or batteries and separates them into four
categories:-
1. According to their condition, effected by disease to the point where they would be condemned p0n
post mortem.
2. The second classification are condemned and destroyed without processing.
3. The third group consists of those birds which show conditions which make them suspects for
possible condemnation upon post mortem inspection. Such birds are processed separately from
healthy carcass and receive special detail inspection.
4. The fourth group consists of those birds affected with pr suspected of having diseases contagious of
humans. After ante-mortem inspection all such live birds can be removed from the plant.
According to US department of meat and poultry inspection manual birds with any of following condition
are considered as suspects:-
1. Dirty ruffled feathers
2. Swellings about head and eyes
3. Lack of lateness or brightness of eyes
4. Gapping of sneezing
5. Off-color diarrhea and or collection of unusual amounts of fecal materials on feather about the vent
6. Skin injuries about the head and neck
7. Visible swelling on body surfaces.
8. Birds are markedly lacking of thrift and well being by their posture.
9. Lameness
10. Enlarged bones
11. Birds showing ascites (When fluid builds up inside the abdomen, it is known as ascites.)
Department of health education condemnation of live birds is recommended when the following
conditions occur:-
1. The bird is down, unable to stand
2. A doughy(fytfytk) feeling of the skin and flesh
3. Partial paralysis, nervous disturbances
4. Unkept appearance
5. Difficulty in respiration etc.

Preparation of ready to cook poultry
 Grading of poultry:-
A. To check the health:- the health and disease free poultry birds are selected for the further
processing to prepare the meat, the birds having any disease are rejected.
B. To check the deformities: - the birds having any deformities of legs, neck, are rejected and
only healthy and sound birds are killed.
C. To check the meatiness: - the birds having high meat contain having strong muscle are
selected for the processing.
 Avoid feeding: - stop the feeding of the poultry birds 12 hours before the slaughtering so that
poultry birds remain empty to avoid the infection. It is also helpful for making hygienic condition.
 Stunning: Stunning prevents struggling and relaxes the muscles holding the feathers. However, it is
generally not practiced in case for chicken. A low voltage electric stunning of 50 volts AC for 1 m
has been found to be satisfactory.
 Bleeding: There are several techniques of slaughtering poultry in order to seek proper bleeding. The
technique most commonly used these days is “modified Kosher Method” in which jugular vein is cut
so that whole blood of the body drain out from 1 to 3 minutes. In general, a bleeding retards the
keeping quality of dressed chicken because blood is a suitable medium for microbial contamination
and if blood will not completely removed the shelf life of the dressed chicken is reduced
 Scalding: Scalding refers to immersion of birds in hot water for loosening the feathers. It should be
done when all reflexes have ceased. The birds are transferred into the scalding tank. Broiler and
young birds are scalded at 550C for 1.5 minutes whereas culled birds and spent hens are scalded at
600C for 2 minutes
 De-feathering: The process is carried out in a feather plucker consisting of two drums with rubber
fingers which revolve in opposite directions pulling of feathers from the carcass. Any remaining
feathers are picked up manually.
 Singeing: The carcasses are now singed over a blue flame for 5 to 10 seconds to remove hair like
appendages called filo plumes.
 Washing: The singed carcasses are washed with spray water to remove dirt and reduce the microbial
load.
 Removal of Feet and Oil Gland: The next step involves cutting of feet from tarsometatarsal joint
with a sharp knife and removal of oil gland.
 Evisceration: The carcasses are hung by hocks to the shackles for evisceration. By a slit opening
from the tip of breast bone, abdominal cavity is opened by means of a transverse cut. A circular cut
is made around the vent. The viscera is drawn outside but allowed to remain attached to the carcass
for postmortem inspection. Meanwhile, a slit is made in the skin of the neck for easy removal of crop
and neck. After postmortem inspection, inedible offals, including trachea, lungs, oesophagus, crop,
intestines, gall bladder and kidneys are removed whereas giblet consisting of heart, liver and gizzard
should be collected, cleaned and packed in a wrapper.
 Chilling and Draining: After washing, the dressed birds are chilled in a chilling tank containing
slush ice or crushed ice for 30-45 minutes in order to cool the carcasses to an internal temperature of
about 40C. The chilled birds are kept on the draining rack for 10 minutes to remove the excess water.
 Washing: Dressed birds are thoroughly washed again with clean spray water preferably maintained
at 15±50C. Special care should be taken to wash the interior and sides.
 Grading: Dressed chickens are graded on the basis of conformation, degree of fleshing, bruises, cuts
and other quality attributes.
 Packaging: Before packaging, dressed chickens having gizzard without mucosal layer, heart without
pericardium and liver without gall bladder are placed in the abdominal cavity of the carcass and
packed in polyethylene bags (200 gauge). Shrink packaging may be adopted if dressed chickens are
to be stored in a frozen condition.

 Storage: Dressed chicken can be stored in a refrigerator at 20C for 7 days and deep freezer at -18 to
-200C for a period of 4-6 months.
Flow diagram for Ready to cook poultry processing
Grading of poultry birds
Avoid feeding
Stunning
Bleeding
Scalding
De-feathering
Singering
Washing
Evisceration
Postmortem inspection
Washing
Chilling
Grading of meat
Packaging
Storage
Indian standards for dressed chicken
Grade 1 Grade 2
Conformation
Fleshing
Fat covering
Free of deformities that detract
from its appearance or that affects
the normal distribution of flesh.
Slight deformities such as slightly
curved or dented breast bones and
slightly curved backs may be
present.
The breast is moderately long and
deep, and has sufficient flesh to
give it a rounded appearance with
the flesh carrying well upto the
crest of the breast bone along with
its entire length
The fat is well distributed so that
Slight abnormalities such as
dented, curved or crooked back, or
misshapen legs or wings which do
not materially affect the
distribution of flesh or the
appearance of the carcass or part
The breast has a substantial
covering of flesh with the flesh
carrying upto the crest of the
breast bone sufficiently to prevent
a thin appearance.
The fat under the skin is sufficient
to prevent a distinct appearance of
the flesh through the skin,

Defeathering
there is a noticeable amount of fat
in the skin in the areas between
the heavy feather tracts.
Free of pin feathers, diminutive
feathers and hair which are visible
to the inspector or grader.
especially on the breast and legs
Not more than an occasional
protruding pin feather or
diminutive feathers shall be in
evidence under a careful
examination.
Cuts and tears
Discolouration
Freezer burn
Free of cuts and tears on the breast
and legs.
Free from discolouration due to
bruising, free of clots; flesh
bruises and discolouration of the
skin such as “blue back” are not
permitted on the breast or legs.
May have an occasional pock
marks due to drying of the inner
layer of skin (derma), provided
that none exceeded the area of a
circle 0.5 cm in diameter on
chickens.
The carcass may have very few
cuts and tears.
Discolouration due to bruising;
free of clots;
Moderate areas of discolouration
due to bruises in the skin or flesh.
May have a few pock marks due
to drying of the
Inner layer of skin (derma),
provided that no single area
exceeds that of a circle 1.5 cm in
diameter.
Factor affecting Quality of poultry of meat
The factors which affect the quality of meat are:-
1. Kind and no. of microorganisms: - The main reason which affects the quality of meat is the presence
and species of microorganism present in meat. As a general rule greater the no of microorganism in
meat the spoilage will be fast.
2. Chemical properties of meat:- the high pH value in the meat favour the growth of microorganism but
low pH lower the microbial growth. The meat with high moisture contents with spoilage more
rapidly than meats with low moisture contain, because high moisture contain many microorganism.
3. Physical Properties: - the meat greater exposed areas will spoilage more rapidly as compared to meat
with small exposed area. The meat in pieces will spoilage in more time as compared to grinded meat
because after grinding the surface area increase.
4. Temperature: - Meat should not be stored above the freezing temperature because below freezing
temperature only psychrotrophs can grow but above the freezing point the mold, yeast, and bacteria
can grow easily.
5. Availability of oxygen: - Aerobic condition of the surface of meat favours the microbial growth.
6. Physiological condition of birds before slaughtering: - if animal or birds are exited before slaughter
than there is a metabolism of muscle glycogen. Due to consumption of the glycogen during
excitement less amount of lactic acid produce and due to which pH of the meat increase which
favour the microbial growth. Due to excitement of animal or birds before slaughtering the bacteria
enter in the muscle through pass circulation of the blood which favours fast spoilage the meat.

Structure, chemicalcomposition and nutritive value, spoilage of eggs and preservation
of whole egg and egg products, preparation of egg powder
Structure, Composition and Nutritive Value of Eggs is necessary to effectively preserve its quality during
storage and marketing. There are four main components of hen’s egg:
a. Shell
b. Shell membranes
c. Albumen or white
d. Yolk
The yolk develops in the functional left ovary of the hen as an ovum largely during the final 10 days
before release. After ovulation or release, fully developed ovum or yolk is engulfed in the oviduct where a
gel of albumin or egg white is secreted to surround the yolk for a few hours. Finally, the shell membranes
and the calcareous shell are deposited in the oviduct for nearly 10 hours before the egg is laid.

Shell
The outer protective covering of an egg is shell which comprises around 1% of its total weight. It is
mainly composed of calcium carbonate. The shell contains numerous minute pores on the entire surface,
which are partially sealed by keratin. These pores allow loss of carbon dioxide and moisture from the eggs.
However, a few of them (hardly 2-0) may permit bacterial penetration within the egg under specific
circumstances. Thus shell structure consists of three basic units:
a. Outer cuticle made up of keratin
b. Middle spongy or calcareous layer
c. Inner mammary layer.
Shell membranes
The shell is attached to the shell membranes. The outer thick and inner thin membranes are usually
inseparable except at the broad end of the egg forming an air cell. The shell membranes have effective
barrier against bacterial invasion.
Albumen
The white or albumen portion of egg constitutes about 58% of the total weight of an egg. It occurs in occurs
in four layers as follows:
a. Outer thin layer
b. Outer thick layer
c. Inner thin layer
d. Inner thick white or chalaziferous layer.
The proportion of thin and thick white varies according to the breed and age of the hen. Thick
content is comparatively more. The inner thick white layer surrounds the vitelline membrane of the yolk and
its firm mucin like fibres continue as chalazae which have the specific function of keeping the yolk in the
centre.
Yolk
This constitutes nearly 31% of the total egg weight. It consists of the following four structures from outside:
a. Vitelline membrane
b. Concentric rings of light and dark yolk material
c. Latebra (cone like portion extending to the centre of yolk)
d. Germinal disc (located in the cone of latebra).
Chemical Composition of egg
An egg consists of 11% shell, 58% albumen and 31% yolk. The cuticle of egg shell is composed of a
foaming layer of proteinaceous matter especially keratin. It covers the calcified portion of the shell which is
made up of calcium carbonate (94%) with minor quantities of calcium phosphate (1%), magnesium
carbonate (%) and proteinaceous material especially keratin. The true cell membrane consists of protein
fibres. The inner membrane is comparatively thick.
Egg albumen or white contains approximately 88% water. Most of the solid content is protein. Lipid
content is virtually absent. However, very minute quantity of carbohydrate (0.5%) may be present. Albumen
may be regarded as a protein system consisting of microscopic fibres in a solution of numerous globular
proteins.
Egg yolk contains more than 50% solids, which are mainly lipids (32%) and proteins (16%). Yolk
lipid is composed of mostly triglyceride (65%), good amount of phospholipids (8%) and controversial
cholesterol (5%). The ash content of yolk is about 1%. A little of carbohydrate, usually less than 0.5%, may
also be present.

Chemical composition of egg
Component Total (%) Water (%) Protein (%) Fat (%) Ash (%)
Whole egg
Albumen
Yolk
Shell
00
58
31
11
65.5
88.0
48.0
Calcium
Carbonate
(%)
94.0
11.8
11.0
17.5
Calcium
Phosphate
(%)
1.0
11.0
0.2
32.5
Magnesium
Phosphate
(%)
1.0
11.7
0.8
2.0
Organic
Matter
(%)
4.0
Nutritive Value
An egg contains about six grams of protein. Egg protein is of such a high quality that its biological
value has been taken as 10 and it acts as a standard for evaluating the biological value of other food proteins.
All the essential amino acids required in human diet are present in egg proteins. An egg also provides five to
six grams of easily digestible fat, wherein the proportion of much desired unsaturated fatty acids (especially
oleic acid) is more as compared to most other livestock products. Egg is an important source of fat soluble
vitamins (A, D, E and K) and water soluble vitamins of B-complex group. However, it does not contain
vitamin C.
With very little carbohydrates, egg has a remarkably low caloric value which justifies its inclusion in
the food for people on restricted diet.
Egg is very good source of important minerals such as iron, phosphorus, potassium and trace
elements which are necessary for the formation of blood, bone and soft-tissues. Though cholesterol content
of egg yolk is comparatively high, it is not likely to significantly influence the blood cholesterol level unless
taken indiscriminately because cholesterol is found in blood, nerve tissues and other parts of the human
body as a normal constituent of the cell.
Nutritive value of edible portion of a chicken egg
Component Whole Albumen Yolk
Weight (g)
Water (%)
Food energy (Cal)
Protein (g)
Fat (Total lipids, g)
Total saturated FA (g)
Total unsaturated FA (g)
Oleic (g)
Linoleic (g)
Cholestrol (mg)
Carbohydrate (g)
Fibre (g)
Ash (g)
Calcium (mg)
Iron (mg)
Magnesium (mg)
Phosphorus (mg)
Potassium (mg)
Sodium (mg)
Vitamin A (IU)
Choline (mg)
Inositol (mg)
50
73.7
81.5
6.45
5.75
1.65
3.30
2.2
0.5
230
0.36
0
0.5
27.0
1.5
5.5
12.5
64.5
61.0
590
253.0
16.5
33
87.6
16.83
3.60
Trace
--
-
-
-
-
0.264
0
0.231
2.97
0.033
.97
4.95
45.87
48.18
0
0.4
-
17
51.1
59.16
.72
1.65
3.30
2.2
0.5
230
0.1
0
0.2890
23.97
1.117
2.72
96.73
16.66
8.84
590
253.0
-
0.017

Niacin (mg)
Riboflavin (mg)
Thiamine (mg)
Ascorbic acid (mg)
0.05
0.15
0.055
0
0.033
0.089
-
0
0.076
0.037
0
Spoilage of eggs
All preservation methods for shell eggs have been designed to retard one or more of the following physic-
chemical alterations which lower the quality of egg as it ages. These are the reason for egg spoilage and
quality degradation:
1. As the surface of egg dries, the keratin cuticle shrinks and size of shell pores increases rendering it
easier for gases and microorganisms to pass in and out of the shell.
2. As the warm egg contents also contract, resulting in the formation of air cell.
3. The breakdown of carbonic acid causing loss of carbon dioxide from the albumen is rapid during the
first few hours after an egg is laid. The pH of the white of a freshly-laid egg is between 7.6 and 7.9,
but that is largely due to the presence of CO2, which is slightly acidic. As an egg ages, water and
CO2 diffuse out through pores in the shell, which raises the pH (it becomes more alkaline). The more
alkaline compounds predominate and pH rises. The alkaline pH is responsible for making albumen
thin or watery.
4. As the egg ages, water migrates from the albumen to the yolk which may overstretch, weaken or
even rupture the vitelline membrane.
Microbial Spoilage of Eggs
It was widely believed in nineteenth century that contents of fresh eggs were always sterile. But
further studies told that microorganisms can gain entry into the egg congenitally. However, most of the
contaminants of eggs are of extra genital origin and come in contact with egg shell from the dust, soil and
faecal matter.
The microorganisms on the shell surface usually belong to a mixed group, but those causing spoilage
of egg (generally called rot) are gram-negative in nature which has very simple nutritional requirements.
The microorganisms have to pass through a series of in-built physic-chemical barriers in the egg—the shell,
the shell membranes, the albumen before reaching the yolk where they could easily multiply causing rot.
The mechanism of microbial spoilage can, thus, be divided into three serial steps:
1. Penetration of microorganisms through the egg shell and shell membranes.
2. Colonization of microorganisms on the shell membrane.
3. Overpowering of the antibacterial factors present in the albumen.
Penetration of Microorganisms through the Egg Shell and Shell Membranes

An egg shell contains more than 17000 pores. However, only ten to twelve pores allow the
microorganisms to pass through. The microorganisms either succeed in when the egg contents contract on
cooling or gain entry due to capillary action through pore canals when the shell surface is moist. After
gaining entry through the shell pores, microorganisms come across shell membranes. These membranes act
as bacterial filters and offer maximum resistance to the offending organisms which have succeeded in
penetrating the shell. Mold may also cause rot in eggs under humid storage conditions.
Colonization of Microorganisms on the Shell Membrane
Once the microorganisms reach to shell membrane, they are able to multiply and form colonies. The
colonization is not instant. In the early stages, there is a decline in the microbial numbers. But in the later
stages, multiplication of organisms takes place at a faster rate because by this time albumen becomes heavily
infected. The pH of egg contents move towards neutrality and yolk comes in contact with inner shell
membrane.
Overpowering the Antibacterial Factors Present in the Albumen
Egg white or albumen provides an un-favorable medium for microbial growth because of the
defensive role played by many of its component proteins like lysozyme and conalbumen is particularly
important play important role. Conalbumen is the principal antimicrobial factor present in the egg and its
inhibitory action is more on gram positive as compared to gram negative organisms.
Type of rot Changes in egg Organisms
Green rot
Black rot (Type 1)
Black rot (Type 2)
Red rot
Fungal rot
Albumen becomes green
Blackening of yolk with “faecal
odour”
Green coloured albumen but yolk
is black with “cabbage odour”
Albumen stained red throughout,
Yolk surrounded by custard like
material
Pink spots on egg contents
Black spots on contents
Yellow or green spots on contents
Pseudomonas
Fluorescens
Proteus sp.
Pseudomonas sp.
Serratia sp.
Sporotrichium
Cladosporium
Penicillium
Besides rots, eggs may develop various types of off odour due to bacteria without any apparent signs of
spoilage. These off odours may be musty or earthy (achromobacter sp), hay like (Enterobacter sp), fishy
(E.coli) or that of cabbage water (Pseudomonas sp.)
Preservation and Maintenance of Eggs
A freshly laid egg can be assumed to have a highest quality. Since egg is full of essential nutrients,
deteriorative changes soon start taking place which may pose a danger to the excellent sensory attributes of
this nourishing and satisfying food item. Cleanliness and soundness of shell is the first step to assure the
quality of egg to the consumers. The shell quality deficiencies mostly relate to the production practices
adopted at the farm. Proper handling of eggs can delay the decline in the quality. Following precautions
should be taken during handling of eggs:
 Eggs should be collected 3 to 4 times per day. This will result in less dirty eggs and fewer breakages.
 After collection, eggs should be shifted to holding room maintained at a temperature of about 150C
and 70 to 80% RH atleast for 12 hours.
 Eggs should be properly packed in filler flats with broad end up. Bulk packing should be done in
fibre board cartons.

TECHNOLOGY OF MEAT, FISH AND POULTRY PRODUCTS

TECHNOLOGY OF MEAT, FISH AND POULTRY PRODUCTS

Empfohlen

Empfohlen

Weitere ähnliche Inhalte

Was ist angesagt?

Was ist angesagt? (20)

Ähnlich wie TECHNOLOGY OF MEAT, FISH AND POULTRY PRODUCTS

Ähnlich wie TECHNOLOGY OF MEAT, FISH AND POULTRY PRODUCTS (20)

Mehr von Mohit Jindal

Mehr von Mohit Jindal (20)

Kürzlich hochgeladen

Kürzlich hochgeladen (20)

TECHNOLOGY OF MEAT, FISH AND POULTRY PRODUCTS