Sources of variation in mechanical shear force measures of tenderness in beef from tropically adapted genotypes, effects of data editing and their implications for genetic parameter estimation

Warner-Bratzler shear force measures of tenderness were taken on 2 muscles from 2661 carcasses from 3 tropically adapted breeds: Belmont Red, Brahman and Santa Gertrudis. The data were used to determine suitable methods of editing the raw data and to partition sources of variation for meat tenderness measured in 2 different muscles. The effect of different methods of electrical stimulation was examined: non-stimulated, extra low voltage or high voltage. The results showed stimulation method had a large effect on the mean and variance of the shear force. Non-stimulated slaughter groups were more variable than high voltage treated groups, which were more variable than low voltage treated groups. The effect of stimulation method was greater for shear force measured in M. longissimus dorsi than in M. semitendinosus. The variability in tenderness associated with different methods of electrical stimulation and the larger effect seen for the M. longissimus muscle suggest cold shortening, a processing effect, may have occurred in some of the slaughter groups. Several methods of editing outlier records were used and the effects of removing these records on the partitioning of variances among the independent variables of tenderness were examined. Removal of non-stimulated slaughter groups and other outliers resulted in a large reduction in slaughter group variance and residual variance, with the estimate of heritability for shear force of the M. longissimus increasing from 19 to 39%. Beef tenderness, as measured mechanically, could be improved by selection. However, the fluctuating heritability estimates reflect differences in handling pre- and post-slaughter and thus highlight difficulties in measuring tenderness consistently. The low genetic correlation between the 2 muscles (r g = 0.34) suggests improving overall tenderness of the carcass may be difficult. The large variance of the slaughter date effect within an abattoir (15% of the total variance) presents a problem in achieving consistently tender meat.

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EFFECTS OF POSTMORTEM GLYCOLYSIS ON THE QUALITY OF HOT-DEBONED BOVINE MUSCLE

Canadian Journal of Animal Science ◽

10.4141/cjas90-055 ◽

1990 ◽

Vol 70 (2) ◽

pp. 431-439

Author(s):

H. L. BRUCE ◽

R. O. BALL

Keyword(s):

Electrical Stimulation ◽

Shear Force ◽

Sarcomere Length ◽

Low Voltage ◽

Protein Solubility ◽

Lactate Concentration ◽

Muscle Metabolism ◽

Meat Tenderness ◽

Sarcoplasmic Protein

Meat tenderness may be improved by accelerating muscle metabolism or by damaging muscle structure and increasing the solubility of muscle proteins. Pre- and postrigor protein and collagen solubilities were measured in semitendinosus muscles, removed pre-rigor from 24 Charolais crossbred steer carcasses, that were either unstimulated or electrically stimulated (115 V, 0.25 amp, 60 Hz) within 1 h postexsanguination to accelerate muscle metabolism. Temperature, pH, Hunterlab color reflectance, sarcomere length and lactate concentration were measured during ageing. Shear force was measured on aged (7 d) muscle only. Low voltage electrical stimulation increased glycolytic rate as indicated by significantly (P < 0.05) lower pH and higher L-lactate concentrations of stimulated muscles as compared to control muscles. Total and sarcoplasmic protein solubilities decreased due to ageing, and myofibrillar protein solubility increased; however, collagen solubilities were unchanged. Low voltage electrical stimulation did not affect color reflectance, sarcomere length or shear force, indicating that an increased rate of glycolysis alone was not sufficient to effect increases in meat tenderness. Key words: Beef, electrical stimulation, meat quality, muscle

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The efficacy of high and low voltage electrical stimulation under different chilling regimes

Canadian Journal of Animal Science ◽

10.4141/cjas94-062 ◽

1994 ◽

Vol 74 (3) ◽

pp. 433-442 ◽

Cited By ~ 18

Author(s):

J. L. Aalhus ◽

S. D. M. Jones ◽

D. R. Best ◽

W. M. Robertson ◽

S. Lutz

Keyword(s):

Electrical Stimulation ◽

High Voltage ◽

Shear Force ◽

Low Voltage ◽

Taste Panel ◽

Interactive Effects ◽

Objective Measures ◽

Beef Quality ◽

Small Magnitude

Two experiments were conducted to determine the efficacy, in terms of beef quality, of low voltage (LV), high voltage (HV) and combined low and high voltage (LH) electrical stimulation under two chilling regimes (blast chilling, BC; conventional chilling, CC).In both experiments, regardless of the type of electrical stimulation, shear values were significantly lower (P < 0.01) in stimulated carcasses compared with non-stimulated control carcasses (CON). Despite the results of the objective measures of shear, taste panel data from exp. 1 indicated a preference for steaks from treatments subjected to high voltage stimulation (HV and LH; P < 0.01). Colour of the musculature in electrically stimulated carcasses was significantly lighter and brighter than CON carcasses in both experiments. However, in exp. 2, where LV was applied for 40 s, a small proportion (~ 10%) of the carcass sides exhibited a pale, soft, exudative condition. This was reflected in the significantly higher drip losses in the LH and LV treatments in exp. 2. Overall, these results indicate an advantage of HV over LV stimulation. Since high voltage stimulation resulted in improved objective measures of meat quality and improved palatability, its use can be recommended to Canadian packers.Under the blast chilling conditions employed in the present studies there were no significant interactive effects with electrical stimulation. Blast chilling resulted in a significant reduction in cooler shrink (P < 0.01), a darker meat colour (P < 0.01) and slightly higher shear force values. The small magnitude of the increase in shear force (approximately 0.3 kg) was not identified by the taste panel and is unlikely to be detected by consumers. Key words: Beef quality, high voltage, low voltage, electrical stimulation

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The beef tenderness model

South African Journal of Animal Science ◽

10.4314/sajas.v45i3.2 ◽

1970 ◽

Vol 45 (3) ◽

pp. 234-248 ◽

Cited By ~ 1

Author(s):

L Frylinck ◽

A O'Neil ◽

E Du Toit ◽

PE Strydom ◽

EC Webb

Keyword(s):

Electrical Stimulation ◽

Connective Tissue ◽

Shear Force ◽

Production Systems ◽

Drip Loss ◽

Meat Tenderness ◽

Phase 2 ◽

Proteolytic System ◽

Beef Tenderness ◽

Feed Withdrawal

In Phase1 of this study, three breed types (Simmentaler-, Brahman- and Nguni bulls; n = 60 each) were grain-fed and slaughtered at 12 months of age (A-age, fat-class 2). Feed was withdrawn for either three hours or 24 hours pre-slaughter. Within each feed withdrawal group, three electrical stimulation (ES) treatments were applied, viz. ES for 15 seconds, 120 seconds or no stimulation. In Phase 2, the effects of animal age and feeding regime were investigated using of A-age (feedlot and pasture), AB-age (feedlot and pasture) and B-age (pasture) animals. All carcasses were electrically stimulated for 15 seconds. Longer feed withdrawal increased dark-firm-dry (DFD) meat occurrence (pHu >6) in the Nguni and Simmentaler-cross. Brahman-cross longissimus (LL) tended to be more tender with paler colour and higher drip loss when 120 ES was applied. Longer feed withdrawal recorded higher Warner Bratzler shear force (WBSF) than three hour feed withdrawal. However, ES neutralized the effect of stress on tenderness. On average the AB-age feedlot animals produced the most tender LL followed by the B-age pasture and A-age feedlot which was similar to the AB-age pasture. A-age pasture animals produced the least tender LL steaks. The calpain proteolytic system played a pivotal role in determining the ultimate meat tenderness and although connective tissue becomes less soluble in older animals it did not play the determinant role in tenderness in this study. The intramuscular fat (< 3%) played an important role in the tenderness outcome of Nguni LL which marbled well at AB-age.Keywords: Meat tenderness, pH and temperature decline profile, pre- and post-slaughter conditions, production systems

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Timing and duration of low voltage electrical stimulation on selected meat quality characteristics of light and heavy cattle carcasses

Animal Production Science ◽

10.1071/an18161 ◽

2020 ◽

Vol 60 (7) ◽

pp. 967

Author(s):

E. C. Webb ◽

B. Agbeniga

Keyword(s):

Electrical Stimulation ◽

Meat Quality ◽

Shear Force ◽

Sarcomere Length ◽

Low Voltage ◽

Carcass Weight ◽

Drip Loss ◽

Early Application ◽

Early Stimulation ◽

Stimulation Parameters

Context The present study investigated the effects of several electrical-stimulation parameters with conventional chilling of heavy- and light-grade carcasses from commercial feedlot cattle on selected meat-quality attributes. Aims The aim was to determine the combination of electrical-stimulation parameters that produced the most desirable results in terms of meat quality, which will serve as a guide to processors seeking to enact best processes in the meat industry. Methods Low-voltage electrical stimulation (110 V peak, 17 pulses/s, 5-ms pulse width) was applied either early post-mortem (PM) at 7 min or late PM at 45 min, for either 30 or 60 s on steer carcasses (n = 98) divided into two weight categories (light (≤260 kg) and heavy (≥290 kg) grades). The Longissimus lumborum muscle was evaluated for sarcomere length, myofibril fragment length (MFL), calpain-1, calpastatin, shear force and drip loss (3 and 14 days PM). Key results There were no significant differences in sarcomere length and no sarcomere shortening was observed. There were minor inconsistencies where early stimulation coincided with marginally longer MFL at 3 and 14 days PM, while late stimulation produced the shortest MFL at 14 days PM. Higher decline in calpain-1 concentration (mean 36.2%) was recorded in the early stimulated carcasses compared with the late stimulated carcasses (mean 29.7%) from 1 to 24 h PM, while calpastatin concentration decreased at a similar rate (mean 24%). Early stimulation resulted in lower shear force (P < 0.05) at 3 days PM, especially in the heavier carcasses, indicating that higher initial temperature did accelerate tenderisation. At 14 days PM, there were no significant differences in shear force as regards stimulation time or carcass weight. Higher drip loss was however recorded in the early stimulated carcasses. Conclusions Early application of low-voltage electrical stimulation produced faster tenderisation early PM, due to higher rigor temperature, but, after aging for 14 days, all meat was acceptably tender with a lower variability, regardless of the stimulation time and carcass weight. Higher drip loss was associated with higher tenderness, which is normal and not a defect. Implications The use of low-voltage electrical stimulation should be encouraged for its ability to reduce variability in meat quality due to carcass-weight differences, especially in the current feedlot systems.

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Modifications of the Warner-Bratzler shear force method to improve the relationship with pork tenderness1

Proceedings of the British Society of Animal Science ◽

10.1017/s1752756200001678 ◽

1999 ◽

Vol 1999 ◽

pp. 12-12

Author(s):

M.J. Van Oeckel ◽

N. Warnants ◽

Ch.V. Boucqué

Keyword(s):

Shear Force ◽

Quality Attributes ◽

Meat Tenderness ◽

Beef Tenderness ◽

Force Method ◽

Maximal Force ◽

A Value ◽

Important Quality ◽

Cooked Meat ◽

The Relationship

The tenderness of pork is one of the most important quality attributes to the consumer. Since it is very time-consuming and costly to evaluate tenderness by taste panel, Warner-Bratzler shear force (WBSF) is often used as a measure for meat tenderness (Boccard et al., 1981). However, the WBSF method gives a value for the maximal force needed to shear a cylindrical core of cooked meat, while the tenderness perception by the consumer is a result of the biting and chewing experience of grilled or fried meat. Moreover, this method is originally designed for the assessment of beef tenderness. The objective of this study was to evaluate modifications to the WBSF method to improve the correlation with pork tenderness.

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Use of electrical stimulation and chilling to enhance meat tenderness of heavy lambs

Canadian Journal of Animal Science ◽

10.4141/cjas-2014-076 ◽

2014 ◽

Vol 94 (4) ◽

pp. 627-637 ◽

Cited By ~ 1

Author(s):

E. Pouliot ◽

C. Gariépy ◽

M. Thériault ◽

F. W. Castonguay

Keyword(s):

Body Weight ◽

Electrical Stimulation ◽

Factorial Design ◽

Shear Force ◽

Meat Tenderness ◽

Fragmentation Index ◽

Individual Variations ◽

Temperature Dynamics ◽

Temperature Window ◽

Optimal Window

Pouliot, E., Gariépy, C., Thériault, M. and Castonguay, F. W. 2014. Use of electrical stimulation and chilling to enhance meat tenderness of heavy lambs. Can. J. Anim. Sci. 94: 627–637. The aim of this study was to determine if electrical stimulation and chilling can modulate pre-rigor pH–temperature dynamics in order to enhance meat tenderness of heavy lambs produced in Quebec and determine if there is an optimum carcass temperature window to reach pH 6.0. A total of 128 heavy lambs (fasted body weight between 38 and 52 kg) were selected at the abattoir over 8 slaughter days (16 lambs d–1) and assigned to four processing treatments in a 2×2 factorial design: electrical stimulation (ES) or not (NES) and normal (NC) or slow (SC) chilling. Slow-chilled carcasses stayed warmer during the first 12 h postmortem (P<0.001), but reached the same temperature as NC ones thereafter. They also had a lower pH between 2 and 12 h (P<0.05). Stimulated carcasses had a lower pH than NES throughout the first 24 h postmortem (P<0.001), while ultimate pH was similar (P=0.738). Shear force values were improved (P<0.001) by both ES and aging as expected, although chilling had no effect (P=0.400). Stimulation×aging interactions for shear force values (P=0.019) and myofibrillar fragmentation index (P=0.097) indicate that aging began earlier following ES. Sarcomeres were longer for ES compared with NES carcasses (P<0.001) indicating that the latter were subject to cold shortening. Meat from NES carcasses was more prone to be tough, although an important part of NES carcasses provided tender meat. This illustrates the importance of individual variations on tenderness and the multiplicity of factors involved in its development. No optimal window was observed for temperature at pH 6.0.

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High Voltage Versus Low Voltage Electrical Stimulation

Physical Therapy ◽

10.1093/ptj/66.8.1209 ◽

1986 ◽

Vol 66 (8) ◽

pp. 1209-1214 ◽

Cited By ~ 13

Author(s):

Rita A. Wong

Keyword(s):

Electrical Stimulation ◽

High Voltage ◽

Low Voltage ◽

Voltage Versus

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Tenderness of beef round muscles containing injection site lesions or bruises

Canadian Journal of Animal Science ◽

10.4141/a00-076 ◽

2001 ◽

Vol 81 (4) ◽

pp. 441-450 ◽

Cited By ~ 1

Author(s):

P. L. Dubeski ◽

J. L. Aalhus ◽

J. Van Donkersgoed ◽

M. VanderKop

Keyword(s):

Injection Site ◽

Key Words ◽

Shear Force ◽

Lesion Size ◽

Lesion Volume ◽

Meat Tenderness ◽

Meat Processing ◽

Beef Tenderness ◽

Beef Calves ◽

Beef Round

The effect of injection site lesions on shear force was studied in three experiments using beef calves injected at 2 to 6 mo with common vaccines and antimicrobials used in Canada. Lesions produced by clostridial bacterins (Blacklegol® 8, Covexin®-8, Ultrabac® 8), antimicrobials (Nuflor®, Trivetrin™), or a four-way respiratory vaccine (Bovishield™ 4) increased (P = 0.05) shear force values at the site of the lesion and at 2.5 cm from the lesion. The proportion of unacceptably tough meat cores (shear force > 4.6 kg) varied among injectables independent of lesion size. The proportion of unacceptably tough samples was significantly increased up to 7.5 and 12.5 cm from the lesion center for Trivetrin™ and Nuflor®, respectively, but only at 0 and 2.5 cm from the lesion center for the bacterins and Bovishield™ 4. Mean lesion volume varied from 8.6 ± 0.8 cm3 for Bovishield™ 4 to 90.2 ± 6.4 cm3 for one of the clostridial bacterins. The present results suggest that smaller lesions, which may not be identified during meat processing, may have a greater impact on meat tenderness and variability than larger lesions that are removed during processing. Antemortem bruises in two muscles of the round did not appear to affect shear force. Key words: Cattle, beef, tenderness, vaccine, antibiotic, lesion, bruise

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Effect of Transportation and Low Voltage Electrical Stimulation on Meat Quality Characteristics of Omani Sheep

Journal of Agricultural and Marine Sciences [JAMS] ◽

10.24200/jams.vol15iss0pp1-8 ◽

2010 ◽

Vol 15 ◽

pp. 1

Author(s):

Isam T. Kadim ◽

Osman Mahgoub ◽

Waleed Al-Marzooqi ◽

Samera Khalaf

Keyword(s):

Electrical Stimulation ◽

Meat Quality ◽

Shear Force ◽

Sarcomere Length ◽

Low Voltage ◽

Quality Characteristics ◽

Cooking Loss ◽

Longissimus Dorsi ◽

Road Transportation ◽

Fragmentation Index

The aim of this study was to determine the effects of road transportation during the hot season (36 oC) and low voltage electrical stimulation on meat quality characteristics of Omani sheep. Twenty intact male sheep (1-year old) were divided into two equal groups: 3 hrs transported or non-transported. The transported group was transferred to the slaughterhouse the day of slaughter in an open truck covering a distance of approximately 300 km. The non-transported group was kept in a lairage of a commercial slaughterhouse with ad libitum feed and water for 3 days prior to slaughter. Blood samples were collected from the animals before loading and prior to slaughter in order to assess their physiological response to stress in terms of hormonal levels. Fifty percent of the carcasses from each group were randomly assigned to low voltage (90 V) at 20 min postmortem. Muscle ultimate pH, expressed juice, cooking loss percentage, WB-shear force value, sarcomere length, myofibrillar fragmentation index and colour L*, a*, b* were measured on samples from Longissimus dorsi muscles collected 24 hrs postmortem at 2-4 oC. The transported sheep had significantly (P<0.05) higher cortisol adrenaline, nor-adrenaline, and dopamine levels than the non-transported group. Muscles from electrically-stimulated carcasses had significantly (P<0.05) lower pH values, longer sarcomere length, lower shear force value, higher expressed juice, myofibrillar fragmentation index and L* values than those from non-stimulated ones. Transportation significantly influenced meat quality characteristics of the Longissimus dorsi muscle. Muscle ultimate pH and shear force values were significantly higher, while CIE L*, a*, b*, expressed juice and cooking loss were lower in transported than non-transported sheep. This study indicated that pre-slaughter transportation at high ambient temperatures can cause noticeable changes in muscle physiology in sheep. Nevertheless, meat quality of transported sheep can be improved by electrical stimulation post-slaughter.

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