FACTORS AFFECTING BEEF COLOR AT TIME OF GRADING

1989 ◽  
Vol 69 (2) ◽  
pp. 347-355 ◽  
Author(s):  
A. C. MURRAY

The color of the longissimus dorsi (LD) muscles from 7695 beef carcasses was evaluated following carcass grading at a commercial abattoir in the Central Alberta Region. Darker-than-normal beef was found in 3.7% of steer and heifer carcasses. However, the incidence of true dark-cutting beef (i.e., dark in color and with a pH greater than 6.0) was estimated to be only 0.5%. The length of time between stunning and the measurement of color had a major impact on color. The incidence of dark-colored beef was three times higher at 15–18 h than at 23–26 h poststunning, apparently because of incomplete development of muscle color at the earlier times. Carcass fat cover, weight and conformation affected muscle color, with smaller and leaner carcasses yielding higher frequency of dark-colored beef. Other factors influenced muscle color, including: (1) gender, (2) nutritional regime, (3) transit distance, (4) lairage time at the abattoir and (5) weather conditions. All of these could be explained by their effect on the time of color measurement or on carcass size and fatness. These findings indicate that if meat color is evaluated during the first 24 h postslaughter, it may be affected by many factors not related to preslaughter stress. During this time period accurate assessment of ultimate muscle color of the dark-cutting condition of conventionally-handled carcasses is not possible. Key words: Beef, color, dark cutting, stress

2019 ◽  
Vol 3 (2) ◽  
Author(s):  
M. Perry ◽  
M. Pfeiffer ◽  
D. VanOverbeke ◽  
R. Ramanathan ◽  
G. Mafi

ObjectivesMeat color is extremely influential in purchasing decisions as consumers associate a bright-red color with freshness. The type of finishing diet can influence beef color. Previous studies have shown that grass-finished cattle have darker muscle color than grain-finished cattle. With the use of modified atmospheric packaging (MAP), beef purveyors are able to vary the gas compositions within a package and enhance beef color. However, limited studies have determined the effects of modified atmospheric packaging on grass-finished beef color. The objective of this study was to determine how finishing diet and packaging type affects the color of the longissimus dorsi (LD) muscle.Materials and MethodsDuring the stocker period, all of the cattle were on a forage diet. Cattle were then randomly assigned to either a conventional grain-based diet or an alfalfa pasture diet for finishing. Both conventionally and pasture-finished cattle were fed for 91 d. Cattle were slaughtered on the same day at a commercial beef processing facility under normal conditions and chilled for approximately 30 h. After grading, one strip loin from each carcass was collected and transported to Oklahoma State University. At 11 d postmortem, one steak (n = 60) from each strip loin was vacuum packaged and randomly assigned to display. Those steaks were then randomly assigned to PVC, HiOx-MAP (80% oxygen and 20% carbon dioxide), or CO-MAP (0.4% carbon monoxide, 69.5% nitrogen, and 30% carbon dioxide) packaging and were displayed under retail conditions for 5 d. Muscle darkening (MD), muscle color (MC), and surface discoloration (SD) were all analyzed by a trained panel (n = 6). MD was evaluated only on d 0 and MC and SD were scored once every 24 h for 0, 1, 2, 3, and 4 d. Lipid oxidation was measured by thiobarbituric acid reactive substances (TBARS) assay on d 4. Data were analyzed using the Mixed Procedure of SAS.ResultsThere was a significant display day by finishing diet by packaging interaction (P < 0.05) for muscle color and surface discoloration. There was also a significant finishing diet by packaging interaction (P < 0.05) for muscle darkening. Steaks packaged in HiOx-MAP remained the most stable in color and the brightest cherry-red colored throughout display time (P < 0.05) compared with other packaging types. PVC was the most discolored (P < 0.05) on d 3 and 4 when compared to HiOx-MAP and CO-MAP with the grain-finished PVC packaged steaks showing the most discoloration on d 4. Pasture-finished steaks packaged in CO-MAP displayed the darkest colored muscle (P < 0.05) on d 0. Steaks packaged in PVC had a higher amount of lipid oxidation (P < 0.05) compared with other packaging types.ConclusionThese results indicate that HiOx-MAP more effectively maintains the desired beef color of bright cherry-red for pasture-finished beef. The results also indicate that the use of appropriate packaging type can minimize the losses due to discoloration of steaks from either grain or grass-finished beef.


2019 ◽  
Vol 3 (2) ◽  
Author(s):  
J. V. Cooper ◽  
S. Suman ◽  
Z. D. Callahan ◽  
K. C. Kerns ◽  
M. Zigo ◽  
...  

ObjectivesPrevious research revealed a relationship between meat color and beef tenderness and indicated that myoglobin can inhibit calpain-1 in solution. The objective of this study was to determine the extent to which myoglobin and beef color are associated with calpain activity and beef tenderness.Materials and MethodsBeef Longissimus dorsi samples from the left side of Holstein beef carcasses (n = 21) were collected immediately post exsanguination on the processing floor for 0 h analyses. Muscle temperature and pH was measured at 0, 24, and 48 h postmortem. After USDA quality and yield grade determination, steaks (n = 6) were removed from the right side of each carcass (n = 21) at 48 h for analyses at 48 and 336 h postmortem. Color (L*, a*, and b* values), surface myoglobin redox forms, metmyoglobin reducing activity (MRA), total myoglobin concentrations, slice shear force (SSF), Warner-Bratzler shear force (WBSF) were measured. Calpain-1 concentrations and autolysis were determined via Western blot at 0, 48, and 336 h.ResultsDecline in muscle pH was 6.4, 5.8, and 5.6 at 0, 24, and 48 h, respectively. Shear force values at 48 h were 73.19 N for WBSF and 384.21 N for SSF and at 336 h were 48.75 N for WBSF and 260.47 N for SSF. Myoglobin reducing activity at 336 h was positively correlated to WBSF at 48 h and negatively correlated to calpain-1 concentration at 0 h (P < 0.05; Table 9). Color measurements of L* and b* at 48 h were moderately correlated with WBSF at 336 h (P < 0.05; Table 9). The b* measurement at 336 h showed a moderate relationship to calpain-1 concentration at 0 h (P < 0.05; Table 9).ConclusionModerate correlations between color and tenderness measurements taken at 48 h with those taken at 336 h were discovered indicating that myoglobin may impact calpain-1 in vivo.Table 9Correlations (P-values) between selected color and tenderness measurements (n = 21)


Author(s):  
William M. Mendenhall ◽  
Eric D. Brooks ◽  
Stephanie Smith ◽  
Christopher G. Morris ◽  
Curtis B. Bryant ◽  
...  

Abstract Purpose To determine factors that influence insurance approval for definitive proton therapy (PT) for prostate cancer. Materials and Methods Between 2014 and 2018, 1592 insured patients with localized prostate cancer were evaluated and recommended to undergo definitive PT; 547 patients (34.4%) had commercial insurance, whereas 1045 patients (65.6%) had Medicare/Medicaid. Of those with Medicare, 164 patients (15.7%) had Medicare alone; 677 (64.8%) had supplemental plans; and 204 (19.5%) had secondary commercial insurance. Insurance that “covered” PT for prostate cancer implied that it was an indication designated in the coverage policy. “Not covered” means that the insurance policy did not list prostate cancer as an indication for PT. Of all 1592 patients, 1263 (79.3%) belonged to plans that covered PT per policy. However, approval for PT was still required via medical review for 619 patients (38.9%), comparative dosimetry for 56 patients (3.5%), peer-to-peer discussion for 234 patients (14.7%), and administrative law judge hearings for 3 patients (&lt;0.1%). Multivariate analyses of factors affecting approval were conducted, including risk group (low/intermediate versus high), insurance type (commercial versus Medicare/Medicaid), whether PT was included as a covered benefit under the plan (covered versus not covered), and time period (2014-16 versus 2017 versus 2018). Results On multivariate analysis, factors affecting PT approval for prostate treatment included coverage of PT per policy (97.1% had approval with insurance that covered PT versus 48.6% whose insurance did not cover PT; P &lt; .001); insurance type (32.5% had approval with commercial insurance versus 97.4% with Medicare; P &lt; .001); and time, with 877/987 patients (88.9%) approved between 2014 and 2016, 255/312 patients (81.7%) approved during 2017, and 255/293 patients (87.0%) approved thereafter (P = .02). Clinical factors, including risk group, had no bearing on insurance approval (P = .44). Conclusion Proton insurance approval for prostate cancer has decreased, is most influenced by the type of insurance a patient belongs to, and is unrelated to clinical factors (risk group) in this study. More work is needed to help navigate appropriate access to care and to assist patients seeking definitive PT for prostate cancer treatment.


1950 ◽  
Vol 40 (4) ◽  
pp. 356-366 ◽  
Author(s):  
R. A. Lawrie

1. The myoglobin contents of selected muscles in horse, pig, domestic fowl and pigeon, and in the foetuses of horse, pig, sheep and cattle, have been determined.2. The order of increasing concentration of myoglobin in the adult animal (4 years) is given by the series heart, longissimus dorsi, diaphragm and psoas, the figures for draught horse being, respectively, 0·325, 0·465, 0·610 and 0·705% and for pig, 0·203, 0·280, 0·350 and 0·435%, and the ratios of these concentrations being the same in each animal.3. In both draught horse and pig, it is shown that the concentration of the pigment rises rapidly from birth, and that, after 2 years in the horse, and 1 year in the pig, it remains fairly constant, except in the case of horse psoas and diaphragm where there is a slow, but significant, rise throughout life.4. This relationship of myoglobin with age has been shown to be significant at a probability level of 0·1%.


1978 ◽  
Vol 5 (1) ◽  
pp. 1 ◽  
Author(s):  
AJ Hall ◽  
FL Milthorpe

Removal of the rapidly growing fruit from a Capsicum plant reduced the rate of net CO2 uptake by its leaves by up to 30% during the time period explored (0.5 - 7 days). This reduction was associated with increases in both the leaf (to about 200%) and intracellular (to about 30%) resistances, these changes having about equal effects on reducing the rate of CO2 uptake. Changes in photorespiration, dark respiration and CO2 compensation point were very small. The rate of CO2 uptake and the associated resistances were also changed by modifying the light regime and other factors affecting the source-sink balance. Changes in the leaf resistance were not attributable to variations in the internal CO2 concentration or in the water economy of the leaf; its control mechanism remains unexplained. The concentration of soluble sugars in the source leaf was completely unaffected but that of polysaccharides was changed by defruiting and by 50% defoliation. However, variations in the intracellular resistance were not closely related to these changes and there is yet no evidence of the nature of its control mechanism. Changes in both soluble sugars and polysaccharides in the stem were more pronounced than in the leaves.


2018 ◽  
Vol 84 (6) ◽  
pp. 772-775 ◽  
Author(s):  
Neal Bhutiani ◽  
Beunca Graffree ◽  
Robert C.G. Martin ◽  
Amy R. Quillo

The aim of this study was to evaluate potential factors affecting the time period in which a 50 per cent parathyroid hormone (PTH) drop is observed. Eight-seven patients undergoing focused parathyroidectomy between 2011 and 2015, whose PTH values dropped to within normal range, were grouped according to whether they required > or ≤15 minutes after gland excision to achieve a 50 per cent PTH. Groups were compared according to preoperative PTH, calcium, age, glomer-ular filtration rate, and adenoma weight. Lower preoperative and preincision PTH levels were associated with requiring >15 minutes to achieve a >50 per cent drop in ioPTH. Time to >50 per cent ioPTH drop did not affect cure rates at one year, though a >15 minutes requirement was associated with higher serum calcium levels (P = 0.015). Lower baseline PTH and preincision PTH levels are significantly associated with a >15 minutes postexcision time to achieve a >50 per cent drop in ioPTH. Future analyses are warranted to determine whether a longer postexcision time threshold before proceeding with four-gland exploration is warranted in patients with primary hyperparathyroidism and mildly elevated preoperative PTH.


1962 ◽  
Vol 21 (4) ◽  
pp. 935-942 ◽  
Author(s):  
T. N. Blumer ◽  
H. B. Craig ◽  
E. A. Pierce ◽  
W. W. G. Smart ◽  
M. B. Wise

2007 ◽  
Vol 16 (6) ◽  
pp. 741 ◽  
Author(s):  
Richard Southgate ◽  
Susan Carthew

Seed from post-fire ephemeral plants like Yakirra australiense can form an important component of the diet of the bilby, a threatened arid-dwelling bandicoot. An investigation was conducted to determine the factors affecting the production of Yakirra and fire reoccurrence in the Tanami Desert. A simple decision model was produced to assist managers decide where and when to burn and what to expect regarding Yakirra australiense growth following fire and rainfall. The information used in the model may be derived from existing spatial databases that document rainfall and fire history and could be used to map broad-scale temporal change in total vegetation cover and components of habitat suitability for the bilby. The season and magnitude of rainfall and time-since-fire were the most important variables in the production of Yakirra seed. Rainfall >300 mm within a 2-month period of intense-complete burns could result in >5% Yakirra cover, and >100 mm was required for >1% cover. Negligible Yakirra cover occurred in adjacent long-unburnt plots. Total ground cover and spinifex cover varied substantially in relation to mean annual rainfall, but not in relation to substrate type. Long-unburnt spinifex cover was mostly too sparse to carry a fire in the southern part of the Tanami and the growth of non-spinifex vegetation would be necessary to boost fuel loads sufficiently to carry a fire. Generally, more than 41% cover was required to carry a fire but this was also dependent on weather conditions. Managers should aim to burn in late spring or early summer to improve Yakirra production. Fire management to enhance habitat suitability for the bilby would be of most benefit in the northern part of the Tanami Desert where growth rate of vegetation is greater and there is little existing fire age heterogeneity.


Author(s):  
N.G. Gregory ◽  
P.J. Murray

If bovine spongiform encephalopathy were found to be transmitted vertically it might become necessary to remove the spinal cord intact from all beef carcasses. One way of achieving this would be to chine the carcass, thus avoiding contamination of the edible carcass with spinal cord during carcass splitting. In line with this possible development, this study examined whether hot chining would help to tenderise beef longissimus dorsi muscle through a tenderstretch effect. Ten beef animals were slaughtered, dressed and split in the conventional way. One side from each carcass was then chined at 50 min post slaughter and chilled overnight at 1 to 2°C.


2019 ◽  
Vol 263 ◽  
pp. 01002
Author(s):  
Andrej Bisták ◽  
Zdenka Hulínová

Ropeways usually provide access to locations inaccessible to other means of transport. Due to this fact, the construction of ropeways is extraordinarily taxing in terms of both, technology and logistics. The site location is often in terrain difficult to access, which often precludes deployment of common construction mechanisms in ropeway construction. In such case, it is advisable to deploy a transport mechanism independent of the terrain – a helicopter. Functioning as “flying cranes“, the helicopters have been used in construction industry in Slovakia for six decades now. Having amassed positive experience, even the “conventional“ construction industry of the time, especially its ropeway transport segment, started to use the benefits of helicopters, with helicopter deployment subsequently gaining ground and becoming the mainstream technological procedure. Ropeway construction can hardly be feasible without them even nowadays. Throughout the history of helicopter deployment in construction industry, a constant search of improving the efficiency of their work has been under way, necessitated by the helicopter’s sensitivitiy to weather conditions and work procedures alike. The paper presents an analysis of the factors affecting helicopter operation together with a proposed methodology of modeling their work in simulation models and the benefits of such approach.


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