Meat Science Muscle to Meat What is Meat

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Meat Science Muscle to Meat

Meat Science Muscle to Meat

What is Meat Science? • The study of the entire meat industry from the

What is Meat Science? • The study of the entire meat industry from the production of the animal to the preparation of the final product to the marketing of the product

Final Product • Cutability: The amount of saleable retail cuts that can be obtained

Final Product • Cutability: The amount of saleable retail cuts that can be obtained from a carcass. • Dressing Percentage: • Ratio of the dressed carcass weight to the weight of the live animal • (Hot carcass weight/live weight)X 100 • An average =62. 5%

9 Components of Meat Inspection/Facilities Inspection • Sanitation • Ante-Mortem inspection • Post-Mortem inspection

9 Components of Meat Inspection/Facilities Inspection • Sanitation • Ante-Mortem inspection • Post-Mortem inspection • Product inspection • Lab analysis

9 Components of Meat Inspection/Facilities Inspection • Control and Restriction of condemned material •

9 Components of Meat Inspection/Facilities Inspection • Control and Restriction of condemned material • Marking and Labeling • Pest Control • Sewage and Waste Disposal

Slaughtering of animals • Slaughter: The act of killing or butchering of animals in

Slaughtering of animals • Slaughter: The act of killing or butchering of animals in a "correct" way especially for food. Essentials of Slaughter 1. Suffering should be minimum 2. Perfect bleeding should be ensured 6

Treatment of Animal prior to slaughter • • Resting Watering Feeding Fasting 7

Treatment of Animal prior to slaughter • • Resting Watering Feeding Fasting 7

Resting Keeping quality of meat reduced without adequate resting due to: v. Incomplete development

Resting Keeping quality of meat reduced without adequate resting due to: v. Incomplete development of acidity v. Invasion of microbes from intestine Period of rest: v. Depending on species, age, sex & breed v. Usually 12 -24 hours 8

Watering Essential for: v. Reduce microbes load in intestine v. Facilitated skinning v. Electrical

Watering Essential for: v. Reduce microbes load in intestine v. Facilitated skinning v. Electrical stunning is more efficient 9

Feeding Importance: v. Deposition of muscle glycogen v. Development of acidity- Increase keeping quality

Feeding Importance: v. Deposition of muscle glycogen v. Development of acidity- Increase keeping quality of meat v. Good appearance, taste & tenderness of meat 10

Fasting • Should stop feeding few hours before slaughter • Importance: v. Good bleeding

Fasting • Should stop feeding few hours before slaughter • Importance: v. Good bleeding carcass v. Minimize migration of microbes from intestine 11

Slaughtering practices and techniques A. The Humane Method & Conventional Techniques of Slaughter &

Slaughtering practices and techniques A. The Humane Method & Conventional Techniques of Slaughter & B. Traditional and Ritualistic Slaughter a. African Traditional Slaughter b. Jewish Method/Shechita c. Muslim method of slaughter d. Jhakta (Sikh) method 12

A. The Humane Method & Conventional Techniques • Complete state of unconsciousness mechanical, electrical

A. The Humane Method & Conventional Techniques • Complete state of unconsciousness mechanical, electrical or chemical means (Stunning) • Stunning- Painless, Motionless, eliminating excitement and cruelty 13

Steps of Humane Method 1. Stunning: Make unconscious prior to slaughter 2. Bleeding: vertical

Steps of Humane Method 1. Stunning: Make unconscious prior to slaughter 2. Bleeding: vertical hanging position (Head down), - knife through the neck behind the jaw bone and below the first neck bone - sever the blood vessels of the neck and let out blood - bleeding should be as complete as possible

Steps of Humane Method (Cont. ) 3. Skinning: Removing of skin from the body

Steps of Humane Method (Cont. ) 3. Skinning: Removing of skin from the body 4. Eviscerating: open the animal body to dislodge the contents and produce the carcass 5. Postmortem Inspection: Carried out by professional veterinarians 6. Special Measures: Stamped as – INSPECTED/ PASSED/ CONDEMNED 15

Humane Method • Advantages: v. Painlessness (Stunning) v. Eliminating excitement and possible cruelty. •

Humane Method • Advantages: v. Painlessness (Stunning) v. Eliminating excitement and possible cruelty. • Disadvantages: v. Disallowed by rituals and established traditions 16

Stunning in humane Method Stunning: Make unconscious prior to slaughter Methods of stunning: ØDirect

Stunning in humane Method Stunning: Make unconscious prior to slaughter Methods of stunning: ØDirect blow to skull using a club- sheep & goats ØFree bullet fired from a pistol into the skull – cattle & Horse (unsafe) ØCaptive-bolt pistols – Cattle & horse (safe) ØElectrical stunning- 60– 80 V for few seconds ØCarbon dioxide stunning- 85% for 45 s, used in pig 17

Traditional and Ritualistic Slaughter Defer from Humane Method by: v Interpretation of the basic

Traditional and Ritualistic Slaughter Defer from Humane Method by: v Interpretation of the basic tenets governing them v. The animals must be in a state of consciousness at the time they are bled v. The bleeding must also be complete. 18

African Traditional Slaughter Sheep or goat is first securely held on its back on

African Traditional Slaughter Sheep or goat is first securely held on its back on the ground by two or three men while the mouth is grabbed tight and drawn backwards to stretch the neck The slaughterer then cuts the throat transversely with a series of strokes halfway deep into the neck Blood is allowed to drain off until the animal (still tightly held) is motionless or dies. The head is then severed off completely. 19

Jewish Method/Shechita Formulated by following the religious taboos almud T Kosher: meat - right

Jewish Method/Shechita Formulated by following the religious taboos almud T Kosher: meat - right fulfilling the requirement of Jewish law-specified in the Talmud Shochet: person appointed for slaughtering Shomer: person appointed for limbs and meat processing and seal. 20

The rules of Jewish ritual slaughte * Must be alive, healthy & have suffered

The rules of Jewish ritual slaughte * Must be alive, healthy & have suffered no injury * Stunning- forbidden * Diseased or lesion in meat (Terefa)- unfit for consumption * Animals that lie & cannot be made to rise must not be slaughtered * Slaughter the animals with a single deliberate swift action of razor sharp knife. * Structures severed: including the CA& JV * Neck incision-complete, without pause, pressure, stabbing, slanting or tearing * Post mortem examination by Shochet making an incision posterior to the xiphoid process inserting the arm to detect any adhesion in the thoracic cavity. * Kosher -must be sold out within 3 days. 21

Jewish Method/Shechita • Advantages: q No cruelty q respiratory activity, struggle> oxyhemoglobin > good

Jewish Method/Shechita • Advantages: q No cruelty q respiratory activity, struggle> oxyhemoglobin > good color meat • Disadvantages: q. Animal remainconscious for a considerable time q. No stunning- Inhuman (many people) q. Economic loss 22

Muslim method of slaughter (Halal method) • Most widespread • Laws are derived from

Muslim method of slaughter (Halal method) • Most widespread • Laws are derived from the Koran • welfare of the animals is a major consideration (Jewish faith also apply to Muslims) • Death animals, consumptions of blood and swine is forbidden. 23

Rules of halal method Done by - adult sensible Muslim Stunning - allowed Should

Rules of halal method Done by - adult sensible Muslim Stunning - allowed Should done quickly Casting- laid on its back Neck vessels and passages (oesphagus and trachea) are severed by a single slash of a sharp knife must not - in the sight of the beast Prior to killing – should feed water 24

Halal method (cont. ) • Advantages v. Same as Jewish v. Struggling & cardiac

Halal method (cont. ) • Advantages v. Same as Jewish v. Struggling & cardiac action- efficient bleeding • Disadvantage vcontamination by contents of the stomach -waste of blood 25

Jhakta/Sikh method • Instant decapitation process • Sikh, Hindu in the India follows this

Jhakta/Sikh method • Instant decapitation process • Sikh, Hindu in the India follows this method. • Limited to only to sheep and goats • By only one blow head is separated 26

Jhakta/Sikh method (cont. ) • Advantages v. Easy and quick method • Disadvantages v.

Jhakta/Sikh method (cont. ) • Advantages v. Easy and quick method • Disadvantages v. Imperfect bleeding 27

Processing of animal after slaughter 28

Processing of animal after slaughter 28

Processing includes: • • • Skinning Evisceration Splitting Washing Dressing of carcasses & Refrigeration

Processing includes: • • • Skinning Evisceration Splitting Washing Dressing of carcasses & Refrigeration 29

Skinning of animals Precautions: • Outer side of the skin must never touch the

Skinning of animals Precautions: • Outer side of the skin must never touch the skinned surface • Operators must not touch the skinned surface with the hand 30

Skinning of Cattle q. Combined horizontal/vertical methods v. Head: horn- remove, head-skinned, Detached head-

Skinning of Cattle q. Combined horizontal/vertical methods v. Head: horn- remove, head-skinned, Detached head- cutting through occipital joint, Hang head- on a hook (Hanging animal) v. Lower the carcass on its back- dressing cradle v. Legs: § Skin & remove the legs at carpal & tarsal § Hooves may be left attached to the hide § Forelegs should skinned after carcass is lowered on to the dressing cradle – to avoid 31

Combined methods (cont. ) Flaying: ØCut skin-along middle line from sticking wound to tail

Combined methods (cont. ) Flaying: ØCut skin-along middle line from sticking wound to tail ØSkin brisket & flanks, working backwards toward the round – with long strokes & keeping knife up to prevent cuts ØSkin udders-without puncturing glandular tissue ØRaise the carcass: half-hoist position shoulders resting on cradle & rump at good height. ØAnal region: v. Clear skin carefully from around anus avoiding puncturing it v. Cut abdominal wall carefully around rectum v. Tie off with twine to seal it v. Skin the tail, raise carcass free of floor & finish flaying 32

Vertical methods • Modern plants have overhead rails- Hide removal is carried out on

Vertical methods • Modern plants have overhead rails- Hide removal is carried out on the hanging carcass • Operations are similar to combined method • It is not possible to reach the hide from ground level more than one operator is needed • Single operator-work with hydraulic platform • Automatic hide pullers - high-throughput 33

Evisceration of cattle combined horizontal/ vertical system Vertical system Carcass is cut along midline

Evisceration of cattle combined horizontal/ vertical system Vertical system Carcass is cut along midline through brisket & abdomen brisket is sawn along midline when the carcass on cradle raised to half-hoist Viscera will come out position and as the carcass in abdominal cavity is cut hanging position carefully along middle line. Separated into carcass is then fully hoisted thoracic viscera, to hang so that the viscera paunch & intestines fall out under their own weight Stomachs or intestines if use for consumption they should tie separately.

Evisceration of small ruminants A small cut is made in the abdominal cavity wall

Evisceration of small ruminants A small cut is made in the abdominal cavity wall just above the brisket Fingers of the other hand are inserted to lift the body wall away from the viscera cut is continued to within about 5 cm of the udder The omentum is withdrawn & viscera taken out Breastbone is split down the middle & thoracic organs then removed 35

Carcass splitting in cattle Work facing the back of the carcass Split the carcass

Carcass splitting in cattle Work facing the back of the carcass Split the carcass down the backbone (chine) with a saw or cleaver from the pelvis to the neck If a cleaver is used, it may be necessary to saw through the rump and loin in older animals The saw and cleaver should be sterilized in hot (82°C) water between carcasses

Carcass splitting in small ruminant • Generally sold entire • Can be split by

Carcass splitting in small ruminant • Generally sold entire • Can be split by saw or cleaver • Saw will probably be necessary for older animals 37

Carcass splitting in pig • Split down the backbone as for cattle • But

Carcass splitting in pig • Split down the backbone as for cattle • But the head is generally left intact 38

Carcass washing Objectives: v. Remove visible soiling & blood stains v. Improve appearance after

Carcass washing Objectives: v. Remove visible soiling & blood stains v. Improve appearance after chilling • Recommendations : ØWater must be clean ØSoiled carcasses should be sprayed immediately before the soiling material dries ØRemove stains from the skinned surface, internal surface, sticking wound & pelvic region. 39

Carcass dressing Objectives: ØRemove all damaged or contaminated parts ØStandardize the presentation of carcasses

Carcass dressing Objectives: ØRemove all damaged or contaminated parts ØStandardize the presentation of carcasses Recommendations: ØInspection should be done by veterinarian ØSigns of disease/damage - entire carcass/offal may be condemned ØFactory personnel must not remove any diseased parts until they have been seen by the inspector otherwise they mask a general condition which should result in the whole carcass being condemned. ØAny instructions from the inspector to remove and destroy certain parts must be obeyed. 40

Refrigeration of carcasses Objectives: v. Retard bacterial growth & extend the shelf-life Recommendations: ØChilling

Refrigeration of carcasses Objectives: v. Retard bacterial growth & extend the shelf-life Recommendations: ØChilling meat after postmortem down to 0°C & keeping it cold will give a shelf-life of up to three weeks ØMust be placed in the cooler immediately ØMust hang on rails & never touch the floor Ødeep muscle temperature of 6– 7° C should be achieved within: v 28 to 36 hours in beef v 12 to 16 hours for pork v 24 to 30 hours for mutton 41

Refrigeration (cont. ) • Humidity and Air current of cooler: Ø High air speeds

Refrigeration (cont. ) • Humidity and Air current of cooler: Ø High air speeds (AS)-rapid cooling but- evaporating wt losses Ø High RH- condensation on the carcass surface favouring mould and bacteria growth Ø Optimum RH=90% & AS=0. 5 m/s Ø Cooler-thoroughly washed before refilling Ø Personnel handling - should follow the strictest hygiene 42

Splitting Evisceration Completion of flaying, cut breastbone Gradually lifting up to dressing rail, continue

Splitting Evisceration Completion of flaying, cut breastbone Gradually lifting up to dressing rail, continue flaying Lowering on skinning cradle, start flaying, cut feet, head & tail Bleeding on bleeding rail Stunning Sequence of operation (combined method) 43

Splitting Evisceration Mechanical hide pulling Transfer from bleeding rail to dressing rail Bleeding Stunning

Splitting Evisceration Mechanical hide pulling Transfer from bleeding rail to dressing rail Bleeding Stunning Sequence of operation (vertical method) 44

REFERENCES 1. Fidel Toldrá (EDITOR ) “Handbook of Meat Processing”, A John Wiley &

REFERENCES 1. Fidel Toldrá (EDITOR ) “Handbook of Meat Processing”, A John Wiley & Sons, Inc. , publication ( 2010) 2. Joseph Kerry, John Kerry and David Ledward (Editors) “Meat processing Improving quality” CRC Press LLC and Woodhead Publishing Ltd(2002) • 3. Dr M. F. W. te Pas, Dr M. E. Everts and Dr H. P. Haagsman, “MUSCLE DEVELOPMENT OF LIVESTOCK ANIMALS Physiology, Genetics and Meat Quality, CABI Publishing (2004)