Bleeding in slaughtered animals and it's effect in meat quality

About carcass bleeding and how to know the efficiency of bleeding and its effect on meat quality.
Detection of ill bleeding carcass
Deffrintial diagnosis between ill bleeding carcass and dead animal before slaughtering.
Pictures showing ill bleeding in the carcass

1. Nourhan Sayed Toufiek Master of Veterinary Medicine, Department of Hygiene and Control of Meat, Poultry, Fish and Their Products.

2. Bleeding of slaughtered animal

3. The object of bleeding is to remove the blood as completely and rabidly as possible from the carcass. Amount of blood in body of animal is 1/12 from its weight and during bleeding may be half or more may be get out.

4. Function of bleeding is to remove more quantity of blood from carcass in few time because blood consider a good media for growth and multiplication of microorganism

5. Bleeding does not lead to evacuation of whole blood, nearly one third of which remain in the tissue and organs of the slaughtered animals what is called " residual blood“ The quantity of blood obtained varied according to: sex , age, live weigh, slaughter method as well as physical condition at time of slaughter. The " residual blood" remaining in liver, muscles, spleen and heart.

6. Blood retained in large amount in the animal body in diseased condition, fever, infectious disease .

7. To ensure completely bleeding the animal should be healthy before slaughter and left to bleed thoroughly for about 5: 10 minute

8. Effect of fever and mechanical cause in the carcass Fever Mechanical cause Congestion of organs with systemic changes fatty change , cloudy , swollen greasy texture Congestion without systemic changes Blood is seen retained in the carcass

9. A- Carcass 1- Not congested subcutaneous blood vessels, axillary’s B.V. and intercostals B.V . 2- Meat appearance not congested . B - Internal organs :- 1- Heart:-Left ventricle completely empty from blood. 2-There is no congestion in the inter organs special(liver, Kidney and lung). Sings of sufficient or good bleeding :-

10. 1- congested subcutaneous blood vessels. 2-Lymph nodes appeared likely covered with blood specially prescapular L.n . but with out enlargement . 3- congested axillary’s blood vessels, and inter costal blood vessels . Sings of ill bleeding: -

11. 4- Meat appearance congested flabby and the carcass appear dark in colour . 5- Left ventricle of the heart full with blood . 6- congestion in the inter organs special (liver, Kidney and lung). 7- Oozing blood in the place when use cut or incision in the masseter muscle

12. ill bleeding carcass

13. Bovine Carcass generalized congestion

14. Well bleeding carcass

15. 1. Sign of normal incision is not seen 2. All veins under skin of head filled with blood 3. Colour of muscle dark 4. There is green colour in abdomen wall and fat arrounded kidney and liver become superficial 5. abdomen cavity contain undesirable odour Slaughtering of animal after death:

16. Diagnosis of imperfectly bleeding

17. Physical test Hemoglobin extraction test Blotting paper Use of compressorium

18. Hemoglobin extraction test In a clean test tube put 5g of chopped meat and add 10ml of water(few drops of ether may be added) shake well and allow to stand for 10 minutes . Result: - faint to faint pink indicate well bleeding(fit) - red to dark red indicate ill bleeding(un fit)

19. Filter paper pressing test: Meat piece ,filter paper, put it between two slide and compressed it and closed to squeeze for 3 minuite Result: - Paint to faint pink indicate well bleeding(fit) - Red to dark red bleeding and oozing in filter paper indicate ill bleeding(un fit)

20. Blotting paper test Meat piece, knife, filter paper Procedure: In a block of meat an incision is made, then a stripe of white blotting paper or filter paper was placed in the incision and the paper was removed after 2 minutes . Result: Badly bled meat will stain the paper light or dark red and moisten while well bled meat stain the paper faint pink

21. Chemical test Acid Malachite green test Preparation of meat extract: 6 gram of meat (free from fat , bone, tendons ) + 14 ml distal water in flask and shaking well then left for 20 minute , take the supernanent for the test

22. In small agglutination tube add 0,7 ml meat extract One drop acid malachite green solution Mix well then add one drop hydrogen peroxide Shake the tube until formation of foams and allow to stand for 20 minutes before reading the result

23. Grade colour Judgment 1   Clear and blue Well bled carcass fit for human consumption and preservation 2 Turbid and green Moderate bleeding fit for human consumption Un fit for preservation 3 Cloud and olive green Ill bleed carcass Un fit for human consumption Un fit for preservation

24. Malachite test showed perfect bleeding samples

25. Effect of ill bleeding carcass in meat quality The presence of residual blood in the carcasses would result in an increase of microorganisms and pH in carcasses Blood components, especially hemoglobin, are powerful promoters of lipid oxidation and may decrease the shelf life of meat.

26. Reference . Bórnez R, Linares MB, Vergara H (2009) Microbial quality and lipid oxidation of Manchega breed suckling lamb meat: Effect of stunning method and modified atmosphere packaging. Meat Sci 83: 383–389. 10.1016/j.meatsci.2009.06.010 [PubMed] [ CrossRef ] [Google Scholar ] Vimini , R. J., et al. "Influence of delayed bleeding after stunning on beef muscle characteristics." Journal of Animal Science 56.3 (1983): 608-615 Gregory, Neville G., Lindsay J. Wilkins, and Andrew MS Gregory. "Studies on blood engorgement in beef carcasses." Journal of the Science of Food and Agriculture 46.1 (1988): 43-51 Novita, Andi, et al. "The Assessment of Complete Bleeding on Laying Hens Carcasses (Gallus gallus ) Sold in Traditional Markets in Banda Aceh." The International Journal of Tropical Veterinary and Biomedical Research 8.1 (2023): 28-31.

27. The effect of slaughtering method on carcass bleeding and quality of meat Research

28. Thanks