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RESEARCH ARTICLE

Eating quality of conventionally chilled sheep meat

D. L. Hopkins A B and E. S. Toohey A
+ Author Affiliations
- Author Affiliations

A NSW Department of Primary Industries, Centre for Sheep Meat Development, PO Box 129, Cowra, NSW 2794, Australia.

B Corresponding author. Email: david.hopkins@dpi.nsw.gov.au

Australian Journal of Experimental Agriculture 46(7) 897-901 https://doi.org/10.1071/EA05309
Submitted: 14 October 2005  Accepted: 2 May 2006   Published: 8 June 2006

Abstract

The meat and eating quality of the M. longissimus et lumborum (LL) from 80 adult sheep carcasses was examined. Half of the carcasses were subjected to the full range of electrical inputs that are routinely used at the abattoir: immobilisation, spinal discharge and high voltage stimulation (HVS), whereas the other half of the carcasses were subjected to all electrical inputs except HVS. HVS significantly decreased the first pH values and increased the average predicted temperature at pH 6.0. When the shear force of samples aged for 1 day was examined (n = 77), there was a significant effect of stimulation, such that non-stimulated meat was tougher. For a reduced sample (n = 40), the most influential effect on shear force was aging, with no significant effect of stimulation or interaction between stimulation and aging. This was such that aging reduced the percentage of samples with a shear force above 50 N from 75% after 1 day to 17.5% after 7 days of aging for the 40 LLs. When the LLs were aged for 7 days, there was no effect of stimulation on eating quality traits including tenderness, flavour, juiciness or overall liking. Based on the data for the LLs aged for 7 days, a relationship between overall liking and the overall ranking score was derived. Predicted overall liking scores at each rating score were derived, from which it was determined that to achieve a rating score of 3 (good every day), the overall liking score had to be 57. There was a significant interaction between category (less or greater than 57) and stimulation, such that for the less than 57 category, the mean overall liking score was lower for samples from non-stimulated carcasses (46.1) than those from stimulated carcasses (54.4). In the greater than 57 category, there was no difference between stimulated and non-stimulated samples with mean overall liking scores of 67.2 and 70.8, respectively. In total, 14% of samples had overall liking scores below 57. These results show that the proportion of very poor samples is reduced with stimulation even with aging and this is a very important outcome.

Additional keywords: consumer, electrical stimulation, quality, sheep meat.


Acknowledgments

The financial support provided by the Australian Sheep Industry CRC is gratefully acknowledged. The valuable support and assistance of the management and staff of the meat processing company was paramount in the successful completion of this work and this is acknowledged. The assistance and input given by Alan Gee of Cosign Pty Ltd is appreciated and gratefully acknowledged.


References


AUS-MEAT (1992) ‘AUS-MEAT Language.’ 4th edn. (AUS-MEAT: Sydney)

Denhertogmeischke MJA, Smulders FJM, Vanlogtestijn JG, Vanknapen F (1997) Effect of electrical stimulation on the water-holding capacity and protein denaturation of two bovine muscles. Journal of Animal Science 75, 118–124.
PubMed |
open url image1

Devine CE , Hopkins DL , Hwang IH , Ferguson DM , Richards I (2004) Electrical stimulation. In ‘Encyclopedia of meat sciences’. (Eds W Jensen, C Devine, M Dikeman) pp. 413–423. (Elsevier: Oxford)

Dransfield E, Etherington DJ, Taylor MAJ (1992) Modelling post-mortem tenderisation. II: Enzyme changes during storage of electrically stimulated and non-stimulated beef. Meat Science 31, 75–84.
Crossref | GoogleScholarGoogle Scholar | open url image1

Egan AF , Shay BJ (1988) Long-term storage of chilled fresh meats. In ‘Proceedings 34th international congress of meat science and technology’. pp. 476–481.

Geesink GH, Mareko MHD, Morton JD, Bickerstaffe R (2001) Effects of stress and high voltage electrical stimulation on tenderness of lamb m. longissimus. Meat Science 57, 265–271.
Crossref | GoogleScholarGoogle Scholar | open url image1

Genstat (2004) ‘Genstat 7 Release 7.1.’ 6th edn. (Lawes Agricultural Trust: Rothamsted)

Hanrahan MC, Ferrier G, Shaw F, Brook D (1998) Improving the quality of lamb meat through electrical stimulation of carcasses. Animal Production in Australia 22, 221–224. open url image1

Hopkins DL, Ferrier GR (2000) The tenderness of lamb meat after low voltage stimulation under commercial conditions. Asian-Australian Journal of Animal Science 13((Suppl July 2000 B)), 356–357. open url image1

Hopkins DL, Thompson JM (2001) The relationship between tenderness, proteolysis muscle contration and dissociation of actomyosin. Meat Science 57, 1–12.
Crossref |
open url image1

Hopkins DL, Walker PJ, Thompson JM, Pethick DW (2005) Effect of sheep type on meat eating quality of sheep meat. Australian Journal of Experimental Agriculture 45, 499–507.
Crossref | GoogleScholarGoogle Scholar | open url image1

Hopkins DL, Hegarty RS, Walker PJ, Pethick DW (2006) Relationship between animal age, intramuscular fat, cooking loss, pH, shear force and eating quality of aged meat from sheep. Australian Journal of Experimental Agriculture 46, 879–884. open url image1

Hwang IH, Thompson JM (2001) The interaction between pH and temperature decline early post-mortem on the calpain system and objective tenderness in electrically stimulated beef longissimus dorsi muscle. Meat Science 58, 167–174.
Crossref | GoogleScholarGoogle Scholar | open url image1

Hwang IH, Devine CE, Hopkins DL (2003) Review: The biochemical and physical effects of electrical stimulation on beef and sheep tenderness. Meat Science 65, 677–691.
Crossref | GoogleScholarGoogle Scholar | open url image1

Pearson AM , Young RB (1989) ‘Muscle and meat biochemistry’. (Academic Press: San Diego, CA)

Pethick DW , Cummins L , Gardner GE , Jacob RH , Knee BW , et al (2000) The regulation of glycogen level in the muscle of ruminants by nutrition. Proceedings of the New Zealand Society of Animal Production 60, 94–98.

Pethick DW, Hopkins DL, D’Souza DN, Thompson JM, Walker PJ (2005) Effect of animal age on the eating quality of sheep meat. Australian Journal of Experimental Agriculture 45, 491–498.
Crossref | GoogleScholarGoogle Scholar | open url image1

Shaw FD , Eustace IJ , Warner RD (1996) Electrical stimulation of lamb carcasses. In ‘Proceedings of the 42nd international congress of meat science and technology’. pp. 410–411.

Shaw FD, Baud SR, Richards I, Pethick DW, Walker PJ, . (2005) New electrical stimulation technologies for sheep carcasses. Australian Journal of Experimental Agriculture 45, 575–583.
Crossref | GoogleScholarGoogle Scholar | open url image1

Shorthose WR, Powell VH, Harris PV (1986) Influence of electrical stimulation, cooling rates and aging on the shear force values of chilled lamb. Journal of Food Science 51, 889–892. open url image1

Simmons NJ , Singh K , Dobbie PM , Devine CE (1996) The effect of pre-rigor holding temperature on calpain and calpastatin activity and meat tenderness. In ‘Proceedings of the 42nd international congress of meat science and technology’. pp. 414–415.

Simmons NJ , Gilbert K , Cairney JM (1997) The effect of low voltage stimulation on pH fall and meat tenderness in lambs. In ‘Proceedings of the 43rd international congress of meat science and technology’. (Ed. J Bass) pp. 610–611.

Thompson JM, Gee A, Hopkins DL, Pethick DW, Baud SR , et al. (2005a) Development of sensory protocol for testing palatability of sheep meats. Australian Journal of Experimental Agriculture 45, 469–476.
Crossref | GoogleScholarGoogle Scholar | open url image1

Thompson JM, Hopkins DL, D’Sousa DN, Walker PJ, Baud SR , et al. (2005b) The impact of processing on sensory and objective measurements of sheep meat eating quality. Australian Journal of Experimental Agriculture 45, 561–573.
Crossref | GoogleScholarGoogle Scholar | open url image1

Toohey ES, Hopkins DL (2004) Preliminary data on the rate of glycolysis in ovine carcasses under commerical processing. Animal Production Australia 25, 330. open url image1

Toohey ES, Hopkins DL (2006) Eating quality of commercially processed hot boned sheep meat. Meat Science 72, 660–665.
Crossref | GoogleScholarGoogle Scholar | open url image1

Unruh JA, Kastner X, Kropf DH, Dikeman ME, Hunt MC (1986) Effects of low voltage electrical stimulation during exsanguination on meat quality and display colour stability. Meat Science 18, 281–293.
Crossref | GoogleScholarGoogle Scholar | open url image1

Young OA, Reid DH, Scales GH (1993) Effect of breed and ultimate pH on the odour and flavour of sheep meat. New Zealand Journal of Agricultural Research 36, 363–370. open url image1