Warner-Bratzler Shear Values Research Articles

Effects of growth path and post-slaughter chilling regime on carcass composition and meat quality of ewe lambs

Sixty-five Poll Dorset x (Border Leicester/Merino) ewe lambs. were grown at pasture on one of four growth paths commencing at mean age of 24 weeks and a mean liveweight of 37-5 kg. These were, continuous growth between 24 and 34 weeks (HH), maximum possible growth for 6 weeks followed by weight loss for 4 weeks (HL), no gain for 6 weeks followed by rapid gain for 4 weeks (LH) and weight maintenance (LL). Lambs were slaughtered as soon as possible after LH and HL lambs were the same full weight. There were significant differences between treatments in average growth rate, liveweight, hot carcass weight (HCW) and dressing percentage. After adjustment for HCW, LH had significantly (P < 0.05) less omental and kidney fat than HH, and there was a strong tendency for less subcutaneous fat, intermuscular fat and a lower tissue depth over the twelfth rib (at the GR site). Eye muscle area was significantly larger in LH than HH, but this did not translate to a significant difference in dissectible 'soft tissue' measurement. The Warner Bratzler shear value for LL in the M. longissimus dorsi was significantly higher than LH and HH. There were no differences between treatments for pH, Warner Bratzler shear values of the M. semimembranosus, cooking loss, or the colour measurements using a Minolta chromameter of L* (lightness) or b* (yellowness). The difference in a* (redness) between HL and LH was significant. Warner Bratzler shear values for M. longissimus dorsi and M.semimembranosus were significantly higher at 4�C than 10�C. The a* was significantly higher at 10�C, but there were no differences between L* and b*. There were no interactions between the post-slaughter chilling regime and the pre-slaughter nutritional management. It was concluded that the growth path had little effect on meat quality unless the lamb had been continuously on a restricted diet. Therefore there was some potential for the use of growth paths to manipulate carcass composition, and further research into management systems at pasture is recommended.

The influence of genotype, sex, and dietary lysine on carcass quality characteristics of 230 and 280 lb finishing pigs (1992)

When pigs were fed to 230 Ib, high-lean genotype loin eyes had less visual marbling and a higher saturation index (more vivid or intense color) than medium-lean genotype loin eyes. Loin eye chops from high-lean gilts had greater cooking losses and WarnerBratzler shear values (mechanically tougher) than those from high-lean barrows and medium-lean barrows and gilts. When pigs were fed to 280 Ib, medium-lean genotype loin eyes had a lighter color visually and indicated by Hunter L* values, more marbling, less firmness, more moisture exudate, and a higher chop thaw loss than high-lean loin eyes. Barrow loin eyes had more marbling and less thaw loss than gilt loin eyes. Loin eye chops from high-lean barrows had higher Warner-Bratzler shear values than high-lean gilts and medium-lean barrows and gilts. Dietary lysine levels had minimal effects on carcass Quality for pigs fed to either 230 or 280 lb.; Swine Day, Manhattan, KS, November 19, 1992

Effect of Divalent Cations on Biochemical and Functional Parameters of Pre- and Postrigor Chicken Breast Fillets

The objective of the present study was to compare the effects of sodium, calcium, magnesium, and manganese ions on some biochemical and functional properties of chicken breast fillets prepared from pre- and postrigor muscles. Pre- and postrigor Pectoralis major muscles were treated with isoionic solutions of CaCl2, MgCl2, MnCl2, or NaCl and then cooked. Biochemical, textural, and yield parameters were observed. Upon cooking, pH of the prerigor muscles treated with divalent cations increased .028 units but those treated with NaCl increased .157 units. The pH of postrigor muscles increased .291 units but the change was unaffected by the treatment. Calcium ions and manganese ions increased the ratio of inosine to adenine nucleotides (R values) in the prerigor fillets but the other ions did not. Moisture absorption and cooking losses were greater for the prerigor fillets treated with divalent cations than for those treated with sodium ions. Calcium chloride reduced and MgCl2 increased Warner-Bratzler shear values of prerigor fillets but none of the treatments affected shear values of postrigor fillets. The data indicate that treatment of breast fillets with certain divalent cations, especially calcium ions, can significantly affect fillet quality.

IDENTIFICATION OF THRESHOLD LEVELS FOR WARNER‐BRATZLER SHEAR FORCE IN BEEF TOP LOIN STEAKS

ABSTRACTThreshold Warner‐Bratzler shear (WBS) values were determined by regression analysis of WBS force values and trained sensory panel overall tenderness ratings of beef top loin steaks from A‐ and B‐maturity carcasses (n = 678). Guidelines for retail and foodservice beef were based on 50 and 68% confidence levels, respectively, for overall tenderness ratings of “slightly tender.” Due to the extreme variation in tenderness that exists in the current U.S. beef population, more stringent confidence levels were not practical. Threshold WBS values for retail and foodservice beef were 4.6 and 3.9 kg, respectively. When these values were tested against the population of beef in the National Consumer Retail Beef Study, the 4.6 kg value was 88.6% accurate at determining whether or not a steak would be rated less than “slightly tender”by consumers.

The effect of breed of sire and age at feeding on muscle tenderness in the beef chuck

Steers (n = 59) produced from the mating of Braford, Simbrah, Senepol, and Simmental bulls to Brahman- and Romana Red-sired cows and Brahman bulls to Angus cows were used in this study. Effects of sire breed and age at feeding on muscle tenderness in the major muscles of the chuck when steers were fed to 1.0 cm 12th rib fat were determined. There were no muscle tenderness effects due to sire breed group, with the exception of the serratus ventralis muscle, which was more tender in Brahman- and Braford-sired steers than in Simmental-sired steers. Additionally, the supraspinatus muscle from the yearlings was lower in shear value than that from the calves. The Brahman-sired steers had serratus ventralis muscles with higher percentages (P less than .05) of intramuscular fat than those of Braford-, Simbrah-, and Simmental-sired steers. Fat deposited within the muscle or between muscles in the chuck was not related to muscle tenderness as measured by Warner-Bratzler shear values. Also, percentages of intramuscular fat of the triceps brachii, serratus ventralis, or supraspinatus muscles were not influenced (P greater than .05) by age at feeding.

Comparison of Two Shearing Methods for Objective Tenderness Evaluation and Two Sampling Times for Physical-Characteristic Analyses of Early-Harvested Broiler Breast Meat

Fillets, pectoralis superficialis, were harvested from broiler carcasses immediately after picking (hot-boned), after chilling (chill-boned), or after 24 h of aging post-mortem (age-boned). In Experiment 1, shear-compression shear values were obtained from cooked left-side fillets and compared to Warner-Bratzler shear values obtained from cooked right-side fillets from the same carcasses. In Experiment 2, sarcomere length and pH were determined at the time of boning and were compared to respective values obtained after 24 h of aging. Even though data obtained using the two shear cells were highly correlated (r = .93) over the entire range of values observed, the correlation coefficients derived from data within individual boning times were much smaller and were accompanied by differences in the slopes of the regression lines. Variances associated with boning-time means and shear-method means were significantly different.The conclusion was that comparisons of shear values involving the use of different testing methodologies should only be attempted within narrow ranges of such values. Differences in pH and sarcomere length at the time of boning decreased with fillet aging. Variances associated with pH and sarcomere-length means as a function of the time of boning were quite variable and, in some cases, significantly different.

Alterations in postmortem degradation of myofibrillar proteins in muscle of lambs fed a beta-adrenergic agonist.

Dietary administration of 4 ppm of the beta-agonist L-644,969 (Merck Sharpe and Dohme Research Laboratories) to finishing lambs induced a decrease (10 to 14%, P less than .05) in extractable calpain I activity in the longissimus muscle (LD) at death (d 0). At 4 d postmortem (d 4), extractable calpain I levels in the LD of both control and treated lambs were reduced (P less than .001) from those present at d 0, but the extractable activity in the LD was reduced to a greater extent in control than in treated lambs. Calpain II activity was increased 42% (P less than .005) in LD of treated lambs; however, no significant differences were observed between d 0 and d 4 calpain II activity within treated or control LD samples (P greater than .1). Calpastatin activity was higher in the LD of treated lambs (74% on d 0, P less than .001 and 430% on d 4, P less than .001) than in the LD of control lambs. Measurable cathepsin B activity was decreased (29% on d 0, P less than .05) and measurable cathepsin H activity was increased (10% on d 0, P less than .05 and 10% on d 4, P less than .05) in the LD of treated lambs compared with controls. On d 2, 4 and 6 postmortem, degradation in myofibrils isolated from the LD was lower for treated than for control lambs. Warner-Bratzler shear values for loin chops from treated lambs were higher on both d 3 (111%) and 6 (108%) postmortem than for chops from control lambs (P less than .001). L-644,969-induced decreases in muscle proteolytic capacity may limit postmortem myofibril degradation and contribute to the reduced tenderness observed. This decreased proteolytic capacity may contribute to increased muscularity of L-644,969-treated lambs.

An assessment of the role of pH differences in determining the relative tenderness of meat from bulls and steers

Samples of M. longissimus dorsi from 16–20 month Friesian bulls or steers (80/group) were assessed for a range of meat quality characteristics after being held at ambient temperature for 24h (to avoid cold-shortening) and then at 0–2°C for 6 days. Mean ultimate pH was significantly higher for samples from the bulls (6·35 versus 5·89), and as a consequence, reflectance values were lower, sarcomere lengths were shorter, and expressed juice and cooking losses were lower. Mean Warner-Bratzler shear values did not differ between the groups, apparently because the bull values were mainly above the peak of the pH/shear force curve, while the steer values were mainly below it. There was no evidence that the relationship between shear force and pH differed for samples from the bulls and steers. Results suggested that the increased shear force with increased pH up to 6·2 was at least partly due to a decreased sarcomere length. It is suggested that some of the differences in tenderness between beef from bulls and steers, that have been reported elsewhere, may have been largely due to differences in ultimate pH values.

SUPPLEMENTATION OF SKIM MILK FED TO VEAL CALVES: CARCASS CHARACTERISTICS, CHEMICAL, INSTRUMENTAL, AND SENSORY PARAMETERS

Twenty-four veal calves were randomly assigned to dietary treatments providing four different levels of dietary fat. Fat supplementation of skim milk providing greater energy density (54, 100, 123, and 147 kJ g−1 of digestible protein) resulted in improved carcass characteristics and grades. Fat deposition, as evaluated by increased kidney fat, external fat covering, and intramuscular fat, was significantly improved (P < 0.05). Differences were noted between longissimus dorsi (LD) and semitendinosus (ST) muscles in color values, but color differences were unrelated to treatment. Marbling scores reflected fat supplementation values for ST but not LD muscles. Fat supplementation resulted in improved sensory characteristics with significantly higher scores (P < 0.05) for tenderness in both muscles and juiciness in ST muscles. Warner Bratzler shear values for LD muscles were also significantly lower (P < 0.05) in fat-supplemented groups. Overall, the improvement in carcass and palatability characteristics justify the supplementation of skim milk diets with fat. Key words: DE:DP ratios, veal calves, marbling, tenderness

Chemical and Physical Characteristics of Beef Chuck Muscles: Effect of Electrical Stimulation, Hot Boning and High Temperature Conditioning

ABSTRACTChucks from 12 electrically stimulated steer carcasses were randomly assigned to one of 3 treatments: (1) cold boned [CB], (control), (2) hot boned [HB], and (3) hot boned/time conditioned [HB/TC], (5 hr at 18°C). Infraspinatus, Serratus ventralis, Subscapularis, Supraspi‐natus, Teres major, and Triceps brachii were excised from each chuck according to treatment conditions. No differences (P > 0.05) were noted among treatments for muscle yields, cooking loss, proximate composition, or collagen content; however, differences (P<0.05) were found among muscles. Differences (P < 0.05) were found among treatments and muscles for ultimate pH, sarcomere length, Warner Bratzler shear values, and Hunter color ‘a’ values. Sarcomere length of muscles assigned to CB treatment were longer (P < 0.05) than HB and HB/ TC treatments.

Effect of sampling site within two muscles, bodyweight, sex, and feeding level on the quality of meat from pigs

Abstract Taste panel assessments of the longissimus muscle and objective measurements on two parts of the semimembranosus muscle were used to assess the effects of liveweight (40, 80, 100 kg), sex (male, castrate male, female), and level of feeding on the meat quality of 54 Landrace × Large White pigs. Relative to the darker distal part, the paler proximal portion of the semimembranosus muscle was more tender, had longer sarcomeres, a lower pH, and a slightly lower water-holding capacity. Changes in quality along the longissimus muscle within the loin as assessed by taste panel were small. Differences in tenderness or Warner-Bratzler shear values were small and inconsistent between treatment groups, but meat from the lightweight males was generally less tender. For the dark portion of the semimembranosus muscle, lower ultimate pH values and higher reflectance values were found for the 40 kg group, the castrates and females, and the restricted feeding group. Water-holding capacity improved with increasing ...

YIELD AND TENDERNESS OF CURED CHICKEN ROLL PRODUCTS AS AFFECTED BY WATER ADDITION

Cured chicken roll products were prepared with either skinless breast meat of skinless dark meat from thighs and drumsticks. Similar products were also prepared from pork for comparison. Processing yields were higher for chicken breast meat than for other meat types when added water was greater than 30%. The yield of dark chicken meat products was always the lowest. Added water did not affect (P 0.05) the Warner-Bratzler shear values of the products. Dark chicken meat products were found to be the most tender, while those from pork were the least tender. Increase in mixing time increased (P 0.05) the processing yield of dark chicken meat products.

Effects of oestradiol-17β implantation on performance, carcass traits, meat sensory traits and endocrine aspects of bulls and steers

Twenty-eight Simmental bull calves were randomly allotted to one of three treatments at birth. Ten bulls (IB) and nine steers (IS), castrated within 3 days of birth, were implanted with oestradiol (E 2). The remaining calves were non-implanted, control bulls (CB). Calves were implanted within 3 days of birth and at 200-day intervals until slaughter at 14·8 months of age and at a mean carcass weight of 381·6 kg. Blood samples were taken every 14 days from 9·8 through 14·8 months and serum was analyzed for E 2 and testosterone (T) levels. Carcasses were chilled in a 3 to 7°C cooler. Carcass data were obtained and aged longissimus dorsi steaks were evaluated by a trained sensory panel and a Warner-Bratzler shear (WBS) device. Scrotal circumferences were smaller ( P < 0·0.5) for IB than for CB. Control bulls had heavier weaning weights ( P < 0·05) than IB and higher ( P < 0·05) feedlot gains than IS. Implanted steers required more ( P < 0·05) feed/unit of gain than CB and IB. Implanting bulls with E 2 increased ( P < 0·05) serum E 2 levels and tended ( P < 0·10) to reduce T levels. Serum E 2 in IS and IB were drastically increased ( P < 0·05) for 4 to 6 weeks following re-implantation during the feedlot phase, then sharply declined. Implanted steer carcasses had more youthful maturity scores than CB carcasses. The incidence of hear ring (dark, coarse, band formation) was greater ( P < 0·05) for IB than for IS, probably because of the thinner fat cover ( P < 0·05) on IB. Ribeye areas were smaller ( P < 0·05) and yield grades were higher for IS than for CB. Testicle weights were not significantly different between IB and CB, although variability was greater for IB. Carcass masculinity was least ( P < 0·05) for IS, and IB were less ( P < 0·05) masculine than CB. The only difference in longissimus dorsi sensory traits was that steaks from IB were juicier than steaks from CB. Also, WBS values were lower ( P < 0·05) for IS than for CB.

Liveweight gains and carcass traits of high grade Simmental, Hereford, Africander x Hereford and Brahman x Hereford feedlot yearling steers

Sixty-three high grade Simmental (S), 40 Hereford (H), 96 Africander x Hereford (AH) and 33 Brahman x Hereford (BH) steers were fed high concentrate feedlot rations from about 8 months of age to slaughter at about 12 months to compare their suitability for producing feedlot beef. Selection for slaughter was made when estimated fat cover and liveweight were closest to market requirements (6-10 mm rib fat and 320-360 kg, respectively). The steers were slaughtered in 3 groups and their carcasses electrically stimulated. Mean slaughter liveweights and carcass weights were 398 and 212, 350 and 182, 349 and 189, 335 and 181 kg for S, H, AH and BH, respectively. Daily liveweight gains during the 4 months on feedlot rations were 1.53, 1.37, 1.24 and 1.25 kg/steer, respectively. Fat depths at rib 12-1 3 and sacral crest sites for S, H, AH and BH were 6.2 and 8.1, 7.3 and 10.3, 8.0 and 10.4,7.3 and 10.0 mm, respectively. In the same order, yield of saleable meat was 77.4, 75.7, 76.3 and 77.2%, and the S and BH had less fat trim than H and AH. Warner-Bratzler peak force shear values (kg) and cooking loss (%) were 3.4 and 33, 3.6 and 34, 3.9 and 34, 5.0 and 35 for S, H, AH and BH, respectively. There were no commercially important differences between H, AH and BH in terms of fat cover at preferred carcass weights and tenderness. However, feedlot liveweight gain favoured the H. Although S steers had highest liveweight gains, many steers did not have sufficient fat cover until liveweights were above the preferred range.

Effects of Compudose® implants from birth to slaughter on carcass and meat traits of young bulls and steers (1986)

Implanting young bulls with Compudose® three times from birth to slaughter resulted in performance similar to that of nonimplanted bulls, but decreased masculinity development. Implanted bulls tended to have higher marbling scores, more tender meat, more youthful carcasses, and lighter lean color than nonimplanted bulls. Although both implanted and nonimplanted bulls were more efficient and gained faster in the feedlot than implanted steers, the steers showed very little carcass masculinity and had finer-textured lean. Implanted steers had more youthful carcasses and lower Warner-Bratzler shear values than nonimplanted bulls. However, nonimplanted bulls grew faster, were more efficient, had larger ribeyes and lower yield grade numbers than implanted steers. For large-framed cattle, castration and implanting with Compudose® near birth result in the most desirable combination of performance, carcass, and meat quality traits.

Influence of Zeranol Implants on Growth, Carcass and Palatability Traits in Bulls and Late Castrates

The effects of 0-, 36- and 72-mg zeranol implants were evaluated in intact and late-castrated males. A 36-mg implanted steer treatment group, castrated at the beginning of the trial, was the control. All 36-mg treatment cattle were reimplanted with a second 36-mg implant on d 112; 72-mg treatment cattle were not reimplanted. Late castration was performed on d 115 of the 210-d trial. Intact males implanted with zeranol grew more rapidly than nonimplanted males during the first 112 d, but there was no advantage to the higher dosage level. From d 112 to slaughter, bulls outgained late castrates and produced heavier carcass weights. Bulls had larger rib eyes and a lower lipid content in the 9-10-11th rib section than late castrates. Implanting increased fat thickness in intact males. Early-castrated steers had lower Warner-Bratzler shear values and greater cooking losses than bulls and late castrates, but there was no significant difference in taste panel evaluations. Implanting had little effect on testicular traits. Data from this trial indicate that delaying castration to 1 yr of age does not appear to provide economic advantages over earlier castration.

Shortening and tenderness of pre-rigor heated beef: Part 2 — Effect of heating rate on muscles of electrically stimulated carcasses

This study was conducted to compare the effects of rapid and slow heating rates on muscles from electrically stimulated beef carcasses. Myofibrillar and cooking shortening and related changes were measured with physiograph recordings on pre-rigor M. triceps brachii strips suspended in paraffin oil during heating. Warner-Bratzler shear values were determined on pre-rigor and post-rigor M. triceps brachii samples heated at approximately the same rates at which muscle strips were heated (2°C/2 min and 2°C/12 min), on pre-rigor M. triceps brachii samples heated at 2°C/6 min, 2°C/9 min and 2°C/12 min and on pre-rigor and post-rigor M. triceps brachii and M. longissimus muscle heated similarly at 2°C/12 min. Rapid heating (2°C/2 min) of pre-rigor muscle produced more severe myofibrillar shortening that was complete at higher muscle temperature than slow heating (2°C/12 min). Slow heating, in contrast to rapid heating, resulted in a cooked product of lower shear value in both the pre-rigor and post-rigor states. The slower the heating rate of the pre-rigor M. triceps brachii, the more tender was the product. Heating at a rate of 2°C/12 min produced acceptable tenderness in both the pre-rigor M. longissimus and M. triceps brachii muscles but even greater tenderness when both muscles were heated in the post-rigor state. The tenderizing action of severe muscle shortening could not be induced in electrically stimulated muscle.

Shortening and tenderness of pre-rigor heated beef: Part 1 — Effect of heating rate on muscles of youthful and mature carcasses

Pre-rigor cooked beef is tender if the cooking produces severe shortening. This study was conducted to compare the effects of different heating rates on shortening and tenderness. Myofibrillar and cooking shortening and related changes were measured with physiograph recordings on pre-rigor M. triceps brachii strips suspended in paraffin oil during heating. Warner-Bratzler shear values were determined on M. triceps brachii samples heated at approximately the same rates at which the muscle strips were heated. Rapid heating (2°C/2min) produced more ( p < 0·01) severe myofibrillar shortening that was complete at higher ( p < 0·01) muscle temperatures than slow heating (2°C/12 min). Regardless of animal age, rapid heating resulted in a cooked product that was more ( p < 0·01) tender than that produced by slow heating in the pre-rigor state and slow heating resulted in a more ( p < 0·01) tender product than that achieved by rapid heating in the post-rigor state. Data on muscle shortening and from differential scanning calorimetry suggest that the tenderness produced from pre-rigor rapid heating results from a heat-induced active contraction.

Tenderness of major muscles from three breed-types of cattle at different times-on-feed

Seventy-five steers (9 to 12 months of age) of Angus (n = 25), Brahman (n = 25) and Brahman × Angus (n = 25) breed-types of known history were fed a high-energy diet and five steers from each breed-type were slaughtered after 0, 56, 112, 168 and 224 days on test. At seven days post mortem, the left side of each carcass was fabricated and eight major primals or subprimals were obtained. Steaks were removed from the shoulder clod, strip loin, tenderloin, top sirloin, knuckle, top round, bottom round and eye of round for Warner-Bratzler shear (WBS) determinations and from the strip loin and bottom round for sensory panel evaluations. Steaks from Angus and Brahman × Angus steers were generally more tender than steaks from Brahman steers. Tenderness of steaks from steers of the three breed-types responded to time-on-feed differently: (a) steaks from Brahman steers improved (P < 0·05) in tenderness with increasing time-on-feed for all muscles except the M. psoas major (tenderloin); (b) with the exception of the M. longissimus muscle (strip loin), the tenderness of steaks from Angus steers did not change (P > 0·05) as time-on-feed increased and (c) for the Brahman × Angus steers, five of the ten muscles studied improved (P < 0·05) in tenderness with increasing time-on-feed. ‘Acceptable’ tenderness (WBS values of less than 4·5 kg) for most of the muscles was achieved at feeding periods from 112 to 224 days for Brahman, from 0 to 56 days for Angus and from 56 to 168 days for Brahman × Angus.

Improved Utilization of Dairy Proteins: Coextrusion of Casein and Wheat Flour

Coextrudates were produced from mixtures of rennet casein and wheat flour by thermal extrusion using a Creusot-Loire BC 45 twin screw extruder. The influence of casein and moisture in the feed material and processing variables was investigated by response surface methodology. Dependent variables included expansion, Warner-Bratzler shear values, and responses of a trained texture profile panel. All product characteristics investigated, with the exception of flavor, could be predicted from independent variables of the multiple regression equations. Addition of rennet casein did not alter the normally bland flavor of extruded starches. Casein at 10 to 30% of the total solids did not influence significantly any of the extrudate characteristics, which were governed primarily by moisture content. The two major physicochemical reactions thought to be taking place during the extrusion process were starch gelatinization and protein texturization. Although it was not possible to determine directly the degree of each process, an examination of the role of the independent variables, extrudate microstructure and sensory breakdown, suggested that starch gelatinization plays a dominant role in dictating product characteristics. Casein may be used in a protein-fortified, extruded wheat flour-based product at the contents studied without altering the characteristic bland flavor or crisp texture of extruded wheat flour. However, a wide variety of textures may be obtained by altering moisture content and process variables.