Evidence of Significant Effects of Stunning and Chilling Methods on PSE Incidences

  • Park, B.Y. (National Livestock Research Institute, RDA) ;
  • Kim, J.H. (National Livestock Research Institute, RDA) ;
  • Cho, S.H. (National Livestock Research Institute, RDA) ;
  • Hah, K.H. (National Livestock Research Institute, RDA) ;
  • Lee, S.H. (Animal Products Grading Service) ;
  • Choi, C.H. (Animal Products Grading Service) ;
  • Kim, D.H. (National Livestock Research Institute, RDA) ;
  • Lee, J.M. (National Livestock Research Institute, RDA) ;
  • Kim, Y.K. (National Livestock Research Institute, RDA) ;
  • Ahn, J.N. (National Livestock Research Institute, RDA) ;
  • Hwang, I.H. (Institute of Rare Earth for Biological Application, Chonbuk National University)
  • Received : 2006.03.18
  • Accepted : 2006.06.26
  • Published : 2007.02.01


The current study was conducted to investigate the optimum stunning voltage and chilling regime with emphasis on reduction in pale, soft and exudative (PSE) pork. The experiments were conducted at seven Korean major pig abattoirs using a total of 91,082 industrial population. Frequencies of PSE meat was found to be significantly (p<0.05) increased as stunning voltage was elevated from 220-240 (13.14%), 250-280 (29.32%) to 430 volts (36.74%). Chilling methods after slaughter, either with cold water showing or rapid chilling reduced PSE meat by 22% compared to a classic chiller-based slow chilling regime. The current study also revealed that chiller temperature during the first 90 minutes had a significant (p<0.001) effect on PSE incidences. Pigs chilled between -5 to $7^{\circ}C$ resulted in the lowest PSE meat (17.8%), followed by higher than $7^{\circ}C$ (21.3%) and lower than $-5^{\circ}C$ (37.5%). The current data implies that low voltage stunning method (eg., 220-240 volts), followed by rapid chilling regime, maintaining chiller temperature between approximately -5 to $7^{\circ}C$ could reduce PSE incidences.


Pigs;PSE;Stunning Method;Chilling Method;Chiller Temperature


  1. Beattie, V. E., R. N. Weatherup, B. W. Moss and N. Walker. 1999. The effect of increasing carcass weight of finishing boars and gilts on joint composition and meat quality. Meat Sci. 52:205- 211.
  2. Bertram, H. C., A. Schafer, K. Rosenvold and H. J. Andersen. 2004. Physical changes of signficance of early post mortem water distribution in porcine M. longissimus. Meat Sci. 66:915-924.
  3. Casteels, M., M. van Oeckel, L. Boschaerts, G. Spincemaille and C. V. Boucque. 1995. The relationship between carcass, meat and eating quality of three pig genotypes. Meat Sci. 40:253-269.
  4. Channon, H. A., A. M. Payne and R. D. Warner. 2002. Comparison of $CO_2$ stunning with manual electrical stunning (50 Hz) of pigs on carcass and meat quality. Meat Sci. 60:63-68.
  5. Grandin, T. 1994. Methods to reduce PSE and Bloodsplash. Proc. Allen D. Leman Swine Confr. University of MN. 21:206-209
  6. Hwang, I. H., B. Y. Park, S. H. Cho, J. H. Kim and J. M. Lee. 2004. Identification of Muscle Proteins Related to Objective Meat Quality in Korean Native Black Pig. Asian-Aust. J. Anim. Sci. 17:1599-1607.
  7. Mitchel, G. and J. J. A. Heffron. 1982. Porcine stress syndromes. Adv. Food Res. 28:167-230.
  8. Park, B. Y., J. H. Kim, S. H. Lee, S. H. Cho, I. H. Hwang, K. T. Kim, D. H. Kim, Y. K. Kim and J. M. 2005. Effect of Electrical and $CO_2$ Stunning Methods on Incidence of PSE Pork. J. Anim. Sci. Technol. (Kor.) 47(2):271-276.
  9. Pearson, A. M. 1987. Muscle function and postmortem changes. pp. 155-191. In: The Science of Meat and Meat Products. 3rd Edit. Price and Schwiegert Edit. Food and Nutrition Press Inc. Westport, CN.
  10. Wood, J. D., G. R. Nute, R. I. Richardson, F. M. Whittington, O. Southwood, G. Plastow, R. Mansbridge, N. da Costa and K. C. Chang. 2004. Effects of breed, diet and muscle on fat deposition and eating quality in pigs. Meat Sci. 67:651-667.
  11. Eilert, S. J. 1997. What quality controls are working in the plant? P. 59-63. In: Proc Pork Quality Summit. July 8-9. National Pork Producers Council. Des Moines, IA.
  12. Pearson, A. M. and J. R. Young. 1989. Muscle and Meat Biochemistry. Academic Press, Inc. Harcourt brace Jouanobich, Publishers. pp. 221-230; pp. 405-408
  13. Offer, G. 1991. Modelling of the formation of pale, soft and exudative meat: Effects of chilling regime and rate and extent of glycolysis. Meat Sci. 30:157-184.
  14. Webb, A. J., A. E. Carden, C. Smith and P. Imlah. 1982. Porcine stress syndrome in pig breeding. Proc. 2nd World Congr. Genet. Appl. Livest. Prod., Madrid, 5:588-608
  15. Council Directive (93/119/CEE) of 22 December. 1993. On the protection of animals at the time of slaughter or killing
  16. Nuss, J. I., F. H. Wolfe and F. H. 1980. Effect of post-mortem storage temperatures on isometric tension pH, ATP, glycogen and glucose-6-phosphate for selected bovine muscles. Meat Sci. 5:201-213.
  17. Savell, J. W., S. L. Mueller and B. E. Baird. 2005. The chilling of carcasses. Meat Sci. 70:449-459.
  18. Tarrant, P. V. 1989. The effects of handling, transport, slaughter and chilling on meat quality and yield in pigs. pp. 1-25. In: Manipulating Pig Production II. Proc. Biennial Conference of the Australian Pig Science Asoc. (Ed. J. L. Barnett and D. P. Hennessy). Warribee, Victoria, Australia.
  19. Tornberg, E. 1996. Biophysical aspects of meat tenderness. Meat Sci. 43:S175-S191.
  20. Carballo, J., E. Garcia-Matamoros and F. Jimenez-Colmenero. 1988. Influence of low voltage electrical stimulation and rate of chilling on post-mortem glucolysis in lamb. Food Chem. 29:257-267.
  21. Christine Fischer and R. Hamm. 1980. Biochemical studies on fast glycolysing bovine muscle. Meat Sci. 4:41-49.
  22. Park, B. Y., C. E. Lee, I. S. Kim, S. H. Cho, Y. G. Kim, J. M. Lee and S. K. Yoon. 2003. Comparison of incidence rate of pse pork by fattening period, transport time and lairage time. J. Anim. Sci. Technol. (Kor.) 45(3):483-490.
  23. Hwang, I. H. and J. M. Thompson. 2001. The effect of time and type of electrical stimulation on the calpain system and meat tenderness in beef longissimus dorsi muscle. Meat Sci. 58:135-144.
  24. James, S. J., A. J. Gigiel and W. R. Hudson. 1983. The Ultra Rapid Chilling of Pork. Meat Sci. 8:63-78.
  25. Maria Yla-Ajos, Marita Ruusunen and Eero Puolanne. 2006. The significance of the activity of glycogen debranching enzyme in glycolysis in porcine and bovine muscles. Meat Sci. 72:532- 538.
  26. Devine, C. E., S. R. Payne, B. M. Peachey, T. E. Lowe, J. R. Ingram and C. J. Cook. 2002. High and low rigor temperature effects on sheep meat tenderness and ageing. Meat Sci. 60:141-146.
  27. Offer, G., P. Knight, R. Jeacocke, R. Almond, T. Cousins, J. Elsey, N. Parsons, A. Sharp, R. Starr and P. Purslow. 1989. The structural basis of the water-holding, appearance and toughness of meat and meat products. Food Microst. 8:151- 170.
  28. SAS. 2001. SAS User's Guide. SAS Institute, Gary, NC, USA.
  29. Taylor, A. A. and L. Martoccia. 1995. The effect of low voltage and high voltage electrical stimulation on pork quality. Meat Sci. 39:319-326.
  30. Department of Agriculture and Forestry. 2004. Grading of Animal Products. Seoul, Korea.
  31. Candek-Potokar, M., B. Zlender, L. Lefaucheur and M. Bonneau. 1998. Effects of age and/or weight at slaughter on longissimus dorsi muscle: Biochemical traits and sensory quality in pigs. Meat Sci. 48:287-300.
  32. Channon, H. A., A. M. Payne and R. D. Warner. 2000. Halothane genotype, pre-slaughter handling and stunning method all influence pork quality. Meat Sci. 56:291-299.
  33. Hwang, I. H., B.Y. Park, J. H. Kim, S. H. Cho and J. M. Lee. 2005. Assessment of postmortem proteolysis by gel-based proteome analysis in pig longissimus. Meat Sci. 69:79-91.
  34. Hwang, I. H., C. E. Devine and D. L. Hopkins. 2003. The biochemical and physical effects of electrical stimulation on beef and sheep meat tenderness. Meat Sci. 65:677-691.
  35. Rosenvold, K. and H. J. Andersen. 2003. Factors of significance for pork quality-a review. Meat Sci. 69:219-237.
  36. Maria Kyla-Puhju, Marita Ruusunen and Eero Puolanne. 2005. Activity of porcine muscle glycogen debranching enzyme in relation to pH and temperature. Meat Sci. 69:143-149.
  37. Channon, H. A. 2001. In: Manipulating Pig Production VIII. Proceedings of the Australian Pig Science Association biannual Symposium: 97-106.
  38. Monin, G. and P. Sellier. 1985. Pork of low technological quality with a normal rate of muscle pH fall in the immediate postmortem period: The case of the Hampshire breed. Meat Sci. 13:49-63.
  39. Park, B. Y., I. C. Cho, S. H. Cho, J. H. Kim, J. N. An, I. H. Hwang, S. J. Lee, J. M. Lee and S. G. Yoon. 2002. Critical control points linked to PSE incidence in korea packing plant. 48th ICoMST 1:274-275.
  40. van Laack, R. L. J. M. and F. J. M. Smulders. 1996. The effect of rapid chilling on pork quality in the Netherlands. Congress Proceedings of the 42nd ICoMST: 510-511.
  41. Hwang, I. H., B. Y. Park, S. H. Cho and J. M. Lee. 2004. Effects of muscle shortening and proteolysis on Warner-Bratzler shear force in beef longissimus and semitendinosus. Meat Sci. 68:497-505.
  42. Warner, R. D., R. G. Kauffman and M. L. Greaser. 1997. Muscle protein changes post mortem in relation to pork quality traits. Meat Sci. 45:339-352.
  43. Maribo, H., E. V. Olsen, P. Barton Gade, A. J. Moller and A. Karlsson. 1998. Effect of early postmortem cooling on temperature, pH fall and meat quality in pigs. Meat Sci. 50:115-129.

Cited by

  1. Early postmortem gene expression and its relationship to composition and quality traits in pig Longissimus dorsi muscle1 vol.90, pp.10, 2012,