With the advancement of food technology and new processing techniques in the world, controlling safety and hygiene measures has become quite easy. Growing demands for meat-based products compel the food processors to step ahead and compete in this ever-growing competitive market.
Slaughtering involves the killing of domestic livestock animals for food. According to the Humane Slaughter Act, 1958, the animals are supposed to be “stunned” i.e. made unconscious or insensible to pain before their throats are being slit.
The general step by step process of Slaughtering of Cattle is explained below in an easy manner-
- 1) 1. Receiving Live Cattle–
- 2) 2. Resting-
- 3) 3. Antemortem inspection-
- 4) 4. Stunning-
- 5) 5. Shackling and Hoisting-
- 6) 6. Sticking–
- 7) 7. Dehiding (removing the hide) and head removal–
- 8) 8. Bunging-
- 9) 9. Evisceration-
- 10) 10. Splitting-
- 11) 11. Washing-
- 12) 12. Chilling–
- 13) 13. Storage and Fabrication-
- 14) 14. Processing of the by-products–
1. Receiving Live Cattle–
Firstly they are unloaded from trucks in the slaughterhouse. Generally, they are kept off from feed to make the further dressing procedure easier. However, water should be kept in their holding pen as per the requirements of the Humane Slaughter Act.
If the animals have been traveled from far places in vehicles, they are provided rest overnight before slaughtering. Resting decreases the stress of the animals arisen from the traveling, thus helps in improving the quality of the meat.
How resting of the animal improves the quality of the post-slaughter meat?
If the animals were under stress during traveling, their glycogen reserve will be more utilized for energy production in order to cope up with the stress. And, if the animal is slaughtered immediately after unloading from the truck, the body of the animal will not be able to replenish the depleted glycogen (which was possible with proper resting), thus the slaughtered meat will have less glycogen content.
Since, after slaughter, the live muscle will slowly convert into non-living meat, the aerobic metabolism will be taken over by the anaerobic metabolism. In anaerobic metabolism, the remaining glycogen reserve will be converted to Lactic acid, which acts as an antimicrobial.
Meat of less rested animal → less glycogen content → less formation of lactic acid during anaerobic metabolism→ less antimicrobial property of the meat → less keeping quality of the meat in term of storage→faster spoilage
Meat of well-rested animal → more replenished glycogen content → more formation of lactic acid during anaerobic metabolism → better antimicrobial property of the meat → better keeping-quality of the meat in term of storage → slow spoilage of meat
3. Antemortem inspection-
It is a thorough inspection of live animals before slaughter to identify any disease, since some diseases are unacceptable, as they may affect human health. Also, few diseases are unacceptable from an aesthetic point of view.
It is used to render each animal to become completely unconscious with minimum excitement and discomfort.
Few of the advantages of stunning are-
- Humane method– by not being cruel to the animals by killing them alive
- Decreases pain and suffering of animals – being unconscious, they can’t feel the pain
- Efficient method– better utilization of by-products can be done if less discomfort is created during slaughtering. For example, if the animal is unconscious before slaughter, then an efficient bleeding process can take place, which in turn provides better quality carcass for processing
- Improves eating quality of meat and offals ( internal organs)
- Decreases contamination– stunning provides less discomfort to the animals, so less glycogen depletion because of less struggle of the animal during slaughtering, thus more lactic acid (which has an antimicrobial property to fight against the spoilage micro-organisms) is produced after the muscle is converted to meat.
Few of the worldwide practiced methods of stunning are-
- Puntilla/ Evernazione method
- Percussion method
- Captive bolt pistol method ✓
- Carbon dioxide gas stunning
- Electrical stunning
Now, lets briefly take an overview of the above mentioned stunning methods-
- Puntilla/ percussion Method– Use of a sharp-edged knife to pierce at the back of the neck, i.e. at the junction of the atlas and occipital bone to severe the medulla oblongata. Due to this method, the activity of the heart and lungs is greatly reduced. It requires expertise to perform.
- Percussion method- In this method, hammer, axe or any blunt object is smashed hard on the skull of the animal to make it unconscious. This efficiency of this method can be proportional to the strength of the blow by the hammer. However, this is not followed now, as there is cruelty hidden in it, the animal sees the hammer coming towards it, increasing the nervousness of the animal. Also, if the hammer misses the right spot to render it unconscious, the animal feels tremendous pain and sufferings till death.
- Captive bolt pistol method ✓ Best humane method – In this method, the pistol will be either penetrating or non-penetrating ( striking). In penetrating type, the bullet from the pistol penetrates the skull of the animal, making it unconscious immediately. The brain becomes inedible as the bullet has penetrated inside. In non- penetrating type, due to spring action, the animal is rendered unconscious. The brain remains edible as a by-product.
- Here a short video on Stunning by Captive Bolt pistol method- ( Source- Humane Slaughter Association )
5. Carbon dioxide stunning method- The animals are passed through a gas chamber containing 70 % CO2 gas for 45 seconds exposure time. However, this method is only adopted for smaller animals like pigs etc. Cattles are not stunned using this method.
6. Electrical Stunning method– This method is also adopted for smaller animals only, not cattle. In this method, electrodes having alternative current flow are made contact with the head of the animal, thus making a rapid increase in blood pressure and heartbeat leading to unconsciousness.
5. Shackling and Hoisting-
Shackling means tying the back legs of the animals, either with a chain or with rope to restrain from moving. Then, it is hoisted in the air to facilitate further operations.
Now a sharp blade is inserted in the neck of the animal, severing the jugular veins and the carotid arteries, leading to exsanguination and death. ( exsanguination means bleeding).
Main Slaughter methods followed worldwide are-
- Halal (Muslim) method– Here, no stunning is done, because the ritual belief is that whole blood is not drained after stunning, which is scientifically true also. Completed bled animal will have better meat quality. The throat of the animal is slit even when the animal is still conscious. very painful for the animals.
- Jhatka (Sikh method)- Here the head of the is chopped off with a heavy sharp cutglass in a single stroke. Not used for cattle as Sikhs and Hindus believe cattle as sacred.
- Kosher (Jewish method)- This slaughtering method is followed by the Jewish people. This method requires great perfection and expertise. The process under the Jewish regulations is called Shechita and it claims to be the most Humane slaughter method known. The expert who performs shechita is called Shochet, with a razor-sharpened knife known as Chalaf. Under this method, the animals are to be fully conscious and are killed and bled through one clean stroke of the chalaf. The Chalaf is stuck into the throat of the animal and a highly precise and located cut is made. Thereafter, the skinning is made from the chest to the belly, and the chest is cut open first for inspection and later evisceration.
7. Dehiding (removing the hide) and head removal–
The hides of animals are removed either by mechanical process or manually. The head and shank of the animals are also being removed.
Bunging is a process of providing a stopper or cork to the rectum of the animals to avoid the contamination by the fecal matter to the other body parts of the carcass.
It is the process of removing the internal organs such as intestines, stomach, heart, lungs, kidneys etc. from the carcass. The stomach and intestines contain a large number of bacteria such as E.coli O157: H7, Salmonella etc., which may contaminate the carcass when allowed in contact.
The carcass is now split with a saw and later postmortem inspection is done to identify any unacceptable disease possibility. If any of the body parts is found with minor acceptable differences, that part is trimmed off, otherwise, if unacceptable disease condition arises, then the whole carcass is discarded. Other unwanted parts are also removed off.
The carcass is washed with antimicrobials, ambient temperature water or with organic acid washing, which can act as a hurdle for the microbe’s survival. Further washing, weighing of the trimmed carcass is done.
Chilling is a process of storage of the carcass in the temperature range of 0-4 degree Celsius. Chilling prevents the growth of bacteria which can create spoilage. The lower temperature during the chilling of the carcass, the more inhibition of the harmful spoilage bacteria.
13. Storage and Fabrication-
The carcass is ready to be stored in coolers, which are large refrigerated warehouses with proper maintenance of temperature, relative humidity, and the air flow. Now, fabrication is done i.e. carcass is cut into smaller parts, and further final processing till packaging is done in other processing units in which they are shipped.
14. Processing of the by-products–
The resulting byproducts from the carcass may be skin, intestines, blood, horns etc. The skin of the animals are widely used in leather industries, intestines are used as casings for making sausages, blood may be mixed with either cornstarch or other extenders and used as a filler in the sausages.
- Some inedible byproducts are lips, teeth, fetus, gallbladder, trimmings, hairs, horns, hooves, fleshings etc.
- Some edible byproducts are kidneys, heart, brain, liver, tongue etc.
The evolving food technology and modern food processing techniques should focus on reducing the pain and cruelty to the animals to a ZERO level during slaughter. Animal Slaughter for food cannot be stopped in any case due to the increasing food demand in this ever-growing world population. However, ensuring the adoption of a most humane way of slaughtering techniques can make the animal’s life, pain-free and stressfree.