Register      Login
Animal Production Science Animal Production Science Society
Food, fibre and pharmaceuticals from animals
Shopping Cart: ( empty )
You are here: Home > Journals > AN > EA03257
RESEARCH ARTICLE
Contents Vol 45(5)

New electrical stimulation technologies for sheep carcasses

F. D. Shaw A F , S. R. Baud B , I. Richards C , D. W. Pethick D , P. J. Walker B and J. M. Thompson E
+ Author Affiliations
- Author Affiliations

A Food Science Australia, PO Box 3312, Tingalpa DC, Qld 4173, Australia.

B Department of Primary Industries Victoria, Private Bag 7, Werribee, Vic. 3030, Australia.

C Meat and Livestock Australia, PO Box 3144, South Brisbane, Qld 4101, Australia.

D Murdoch University, Murdoch, WA 6150, Australia.

E University of New England, Armidale, NSW 2351, Australia.

F Corresponding author. Email: fshaw@iinet.net.au

Australian Journal of Experimental Agriculture 45(5) 575-583 https://doi.org/10.1071/EA03257
Submitted: 22 November 2003  Accepted: 12 October 2004   Published: 27 June 2005

Abstract

High voltage electrical stimulation applied to the lamb carcass at the end of the dressing procedure often leads to an improvement in overall product quality by reducing the incidence of toughness. It would be advantageous if the same results could be consistently achieved with the use of lower, safer, voltages — medium voltage electrical stimulation. Experiments were conducted to determine the effect of medium voltage electrical stimulation applied to wool-on carcasses on meat quality as assessed using the Sheep Meat Eating Quality protocols. A further experiment examined the interaction of electrical stimulation and meat aging time on the consumer acceptance of lamb meat. In the first experiment, 3 treatments: control (non-stimulated), medium voltage electrical stimulation (applied to the wool-on carcass) and high voltage electrical stimulation (applied at the completion of dressing) were examined. Samples of the loin (LTL) and rump (GM) muscles were evaluated by consumers using Sheep Meat Eating Quality protocols. For both muscles, the consumers gave higher scores for tenderness, juiciness, flavour and overall acceptability to the stimulated product (P<0.001). There were no statistically significant differences between the 2 stimulation treatments. The second experiment was conducted at a commercial lamb-processing abattoir that had installed a prototype automated electrode system designed to work at chain speed. Lambs received either no stimulation (control), low current medium voltage electrical stimulation (constant current 300 mA peak, 15 Hz, maximum voltage 550 V peak) or high current medium voltage electrical stimulation (constant current 600 mA peak, 15 Hz, maximum voltage 550 V peak) immediately after sticking. Electrical stimulation improved both the objective and sensory (Sheep Meat Eating Quality) eating quality attributes of lamb loin muscle when assessed following 2 days of ageing. When expressed according to consumer satisfaction rating, 30, 37 and 70% of the loins receiving low, high or no electrical stimulation, respectively, were rated as unsatisfactory at 2 days of ageing. At 4 days of ageing no loins from carcasses in the low stimulation treatment were rated by consumers to be unsatisfactory (P<0.05) compared with either non-stimulated (40%) or high-stimulated loins (35%). With respect to the effects of aging meat, electrical stimulation improved the consumer score at 2 days post-stunning by 8.9 and 4.7 points for tenderness and overall liking, respectively. Further linear improvements due to aging were similar for both electrical stimulation and unstimulated products. Under conditions of no electrical stimulation used in this experiment, 10 days aging results in tenderness and overall liking scores greater than 60 and with ES similar scores are achieved in 5 days. Consumer scores over 60 greatly reduce the chance of meat being classified as unsatisfactory.


Acknowledgments

This project relied on the willing assistance of the staff at the Meat Research and Training Centre, VIAS, within the Victorian Government Department of Natural Resources and Environment. We gratefully acknowledge the contribution of Matthew Kerr, Paul Weston and Paul Meredith. The skilled technical assistance and dedication of Mr Malcolm Boyce, Mrs Barbara Waldoch, Mr Ken Chong is gratefully acknowledged. The manager and staff at Hillside Meats are gratefully acknowledged for their enormous cooperation during the slaughter and bone out periods.


Meat and Livestock Australia accepted the muscle samples into their Consumer Sensory Perceptions of Lamb and Sheepmeat Program and provided financial assistance to the project. We thank Alan Gee of Cosign for his assistance with the preparation of the samples for the consumer trials.


References


Anon. (2002) Australian standard AS/NZS 60479 Effects of current on human beings and livestock. Standards Australia, Standards House, North Sydney, NSW.

Bendall JR (1980) The electrical stimulation of carcasses of meat animals. In ‘Developments in meat science’. (Ed. RA Lawrie) p. 37. (Applied Science Publishers: London)

Chrystall BB , Devine CE (1983) Electrical stimulation: its early development in New Zealand. In ‘Advances in meat science. Vol. 1’. (Eds AM Pearson, TR Dutson) pp. 73–119. (AVI Publishers: Westport, CT)

Chrystall BB, Hagyard CJ, Wade L, Ellery S (1984) Combined low and high voltage stimulation of lamb. New Zealand Journal of Agricultural Research 27, 43–47. open url image1

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

Dransfield E (1993) Modelling post-mortem tenderisation. IV. Role of calpains and calpastatin in conditioning. Meat Science 34, 217–234.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Ferguson DM, Bruce HL, Thompson JM, Egan AF, Perry D, Shorthose WR (2001) Factors affecting beef palatability — farmgate to chilled carcass. Australian Journal of Experimental Agriculture 41, 879–891.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Ferguson D , Thompson J , Polkinghorne R (1999) Meat Standards Australia, a ‘PACCP’ based beef grading scheme for consumers. 3. PACCP requirements which apply to carcass processing. In ‘Proceedings of the 45th international congress of meat science and technology’. pp. 18–19. (Yokohama, Japan)

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

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

Hildrum KI, Nilsen BN, Bekken J, Naes T (2000) Effects of chilling rate and low voltage electrical stimulation on sensory properties of ovine m. longissimus. Journal of Muscle Foods 11, 85–98. open url image1

Hopkins DL, Considine MJ, MacPherson ED, Munro BC (1998) Performance of a branded lamb alliance. Animal Production in Australia 22, 299. 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, 356–357. open url image1

Hopkins DL , Ferrier GR , Channon HA , MacDonald BA (1995) Assessment of lamb meat quality in Sydney and Melbourne. In ‘Proceedings of the New Zealand Society of Animal Production’. pp. 112–116.

Hopkins DL, Littlefield PJ, Thompson JM (2000) The effect of low voltage stimulation under controlled conditions on the tenderness of three muscles in lamb carcasses. Asian–Australian Journal of Animal. 13, 362–365. open url image1

Hwang IH , Hearnshaw H , Shaw FD , Thompson JM (1998) The interaction between type (high or low voltage) and time (3 or 40 minutes post-stunning) of electrical stimulation of beef. In ‘Proceedings of the 44th international congress of meat science and technology’. pp. 1052–1053. (Barcelona, Spain)

Lee S, Polidori P, Kauffman RG, Kim BC (2000) Low-voltage electrical stimulation effects on proteolysis and lamb tenderness. Journal of Food Science 65, 786–790. open url image1

McGeehin B, Sheridan JJ, Butler F (2002) Optimising a chilling system for lamb carcasses. Journal of Food Engineering 52, 75–81.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Morton HC, Newbold RP (1982) Pathways of high and low voltage electrical stimulation in sheep carcasses. Meat Science 7, 285–297.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Nilsen BN , Naes T , Skarpeid HJ , Hildrum KI (1998) Effects of tendering treatment on 2 breeds of Norwegian Lamb. In ‘Proceedings of the 44th international congress of meat science and technology’. pp. 468–469. (Barcelona, Spain)

Pethick DW, Hopkins DL, D’Souza DN, Thompson JM, Walker P (2005) The effect of animal age on the consumer perception of sheep meat eating obtained from Merino ewes. Australian Journal of Experimental Agriculture 45, 491–498. open url image1

Pethick DW , McIntyre B , Wiese S (1999) Impact of chiller treatment on tenderness and pH in Western Australian Lamb. Final Report Meat and Livestock Australia Project M.784Q, Murdoch University, Perth, WA.

Pleasants AB, Thompson JM, Pethick DW (2005) A model relating a function of tenderness, juiciness, flavour and overall liking to the eating quality of sheep meat. Australian Journal of Experimental Agriculture 45, 483–489. open url image1

Polidori P , Fantuz F , Lebborni G , Polidori F (2002) Effects of electrical stimulation of wether lamb carcasses. In ‘Proceedings of the 48th international congress of meat science and technology’. pp. 232–233. (Rome, Italy)

Polidori P, Lee S, Kauffman RG, Marsh BB (1999) Low voltage electrical stimulation of lamb carcasses: effects on meat quality. Meat Science 53, 179–182.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Safari E, Channon HA, Hopkins DL, Hall DG, van deVen R (2002) A national audit of retail lamb loin quality in Australia. Meat Science 61, 267–273.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Shaw FD , Eustace IJ , Smith DR (1995) Why we should apply electrical stimulation to lamb carcasses. In ‘Meat ’95. Proceedings of a CSIRO Meat Industry research conference’. pp 11–12. (CSIRO Division of Food Science and Technology: Brisbane)

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. (Lillehammer, Norway)

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, 889–891. open url image1

Simmons NJ , Cairney JM , Daly CC (1997) Effect of pre-rigor temperature and muscle prestraint on the biophysical properties of meat tenderness. In ‘Proceedings of the 43rd international congress of meat sciences and technology’. pp. 608–609. (Auckland, New Zealand)

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’. pp. 610–611. (Auckland, New Zealand)

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 sciences and technology’. pp. 414–415. (Lillehammer, Norway)

Thompson JM, Hopkins DL, D’Souza DN, Walker PJ, Pethick DW (2005b) The impact of processing variables on the consumer perception of sheep meat eating quality. Australian Journal of Experimental Agriculture 45, 000–000. open url image1

Thompson JM, Gee A, Hopkins DL, Pethick DW, Baud SR, O’Halloran W (2005a) Development of a sensory protocol for testing palatability of sheep meats. Australian Journal of Experimental Agriculture 45, 469–476. open url image1

Uruh 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 |
open url image1

Warner RD , Bond JJ , Kerr MG (2000) Meat quality traits in lamb m. longissimus thoracis et lumborum: the effect of pre-slaughter stress and electrical stimulation. In ‘Proceedings of the 46th international congress of meat science and technology’. pp. 154–155. (Buneo Aries, Argentina)