Comparison of meat quality between eland (Taurotragus oryx) and cattle (Bos taurus) raised under similar conditions

Physical, chemical and sensory characteristics of meat were compared between non-domestic eland (Taurotragus oryx) bulls (n = 6) and domestic Fleckvieh (Bos taurus) bulls (n = 6) which were finished under controlled conditions of feeding and management. Musculus longissimus lumborum from eland were darker and less yellow in colour, with a higher pH₂₄ and lower contents of intramuscular fat and total collagen, compared to cattle. Contents (mg/100 g muscle tissue) and proportions (g/100 g of FA determined) of SFA and MUFA were higher (P < 0.01) in cattle. Although the proportion of total PUFA were higher (P < 0.001) in eland, contents of PUFA were similar between species. Meat from cattle was consistently scored higher (P < 0.05) for sensory texture characteristics, juiciness, flavour, and overall acceptance. We concluded that bulls of eland provided low-fat meat with a beneficial fatty acid composition from a human nutrition perspective, but with lower sensory scores, compared to bull beef.     

Variation in bull beef quality due to ultimate muscle pH is correlated to endopeptidase and small heat shock protein levels

This study set out to determine if ultimate pH (pH_u) affected the performance of intracellular small heat shock protein and endopeptidase dynamics in muscle during beef ageing. Longissimus dorsi muscles from 39 Angus or Limousin × Angus bulls were examined to see if pH_u achieved at 22 h post mortem (rigor) affected tenderness and water holding capacity of beef. Samples were segregated into three pH_u groups termed high (pH > 6.3), intermediate (5.7 < pH < 6.3) and low (pH < 5.7) pH_u beef. More than 30% of bull beef did not achieve acceptable tenderness at 8 days post mortem with this ageing regime. No significant differences in calpain or cathepsin enzyme levels due to meat pH were observed until after 22 h post mortem, but low pH_u beef had elevated caspase 3/7 activity soon after slaughter. At 22 h post mortem, greater levels of μ-calpain enzyme were found in the high and intermediate pH_u beef and cathepsin B levels were superior in the low pH_u beef after 2 days post mortem. Different rates of desmin and troponin T protein degradation were also observed in aged bull beef. Both proteins were degraded within 6 h post mortem for high pH_u beef, but took >3 days post mortem for intermediate pH_u beef. High levels of alpha β-crystallin (aβC) at 22 h post mortem coincided with delayed muscle protein degradation for low pH_u beef. Our results support the hypothesis that aβC shields myofibrils and buffers against endopeptidase degradation of beef structure during ageing.     

Eating quality of “Vitela Tradicional do Montado”-PGI veal and Mertolenga-PDO veal and beef

Physicochemical and sensory characteristics were measured in veal and beef from the Portuguese Mertolenga breed having 3 quality labels as follows: Mertolenga-PDO beef and veal which apply to purebred animals and “Vitela Tradicional do Montado”-PGI veal which applies to crossbred animals. Measurements were made in longissimus lumborum muscle aged for 6 days. The temperature 3 h post-mortem (T₃), cooking losses and Warner–Bratzler shear force (WBSF) reflected carcass weight (CW) differences between groups. The pigment content was influenced by age, with beef having higher values than veal. WBSF correlated negatively with intramuscular fat in Mertolenga-PDO beef, but not on veal. WBSF correlated positively with cooking losses and negatively with myofibrillar fragmentation index, tenderness, juiciness and overall acceptability. Cooking losses and juiciness were the main contributors for the tenderness differences. Vitela Tradicional do Montado-PGI and Mertolenga-PDO veal had lighter colour and were considered tender. The three meat types were well discriminated based on pH_u, a* and C* parameters by canonical discriminant analysis.     

Use of serial ultrasound measures in the study of growth- and breed-related changes of ultrasonic measurements and relationship with carcass measurements in lean cattle breeds

The growth and breed-related changes of rib and rump characteristics in lean beef cattle and the ability of ultrasound to predict carcass traits were investigated. Three hundred bulls from three breeds were scanned monthly (6–7 times) using real-time ultrasound with final scans taken < 7 days prior to harvest. The rib and rump ultrasound measurements, except intramuscular fat content, increased (P < 0.05) with live weight. Breed affected most of traits. The 12th rib ultrasound measurements showed a weak to high positive correlation (0.131 to 0.976, P > 0.05 to P < 0.001) with 12th rib measurements in the carcass. Regression equations developed with the ultrasound measurements, explained 97% of the variation in longissimus muscle area, 88% of the variation in fat thickness and 57% of the variation in intramuscular fat content. When last ultrasound scan measurements were excluded from prediction equations, the R² significantly decreased. Ultrasound measures “in vivo” are viable options for assessing carcass attributes of lean cattle.     

A comparison of needle-free and needle-injection methods and solutions for enhancement of beef longissimus lumborum muscles

In Experiment 1, beef strip loins (n = 15) were halved and assigned to needle (N) or needle-free (NF) injection enhancement with a phosphate plus salt solution (PS) to determine effects on color, water-binding, and palatability. Pump yields tended (P = 0.08) to be higher for NF injection. Needle-injected steaks were darker (P < 0.05) on day 1 only. The NF treatment had greater instrumental tenderness and intensity of off-flavors but less cooking loss and beef flavor (both P < 0.05). In Experiment 2, strip loins (n = 28) were halved and assigned to one of four treatments: (1) N, or (2) NF injection with PS; (3) N, or (4) NF injection with a calcium lactate solution (CL) to determine effects on water-binding and palatability. Needle-free injection resulted in a greater incidence (P < 0.05) of off-flavors and abnormal texture. The PS solution resulted in greater (P < 0.05) instrumental, myofibrillar, and overall tenderness; greater juiciness; greater incidence of off-flavors and abnormal texture; and less (P < 0.05) connective tissue and cooking losses than CL. The PS and NF combination had the highest pumped yields and least cooking losses (both P < 0.05). Enhancing beef strip loins with PS and NF injection has potential to improve yield, tenderness, and juiciness but harm texture and flavor.     

Effect of sire breed on physico-chemical and sensory characteristics of lamb meat

Physico-chemical and sensory characteristics of lamb meat were evaluated in crossbred ram lambs from Merino ewes and Oxford Down, Texel, Charollais, Suffolk and Merinolandschaf sires. The lambs were slaughtered at average age 119.2 days, live weight 34.6 kg and carcass weight 16.3 kg. Samples of M. longissimus lumborum et thoracis were used for measurements of pH values, electrical conductivity (EC), drip loss, contents of dry matter (DM), protein, intramuscular fat (IMF), ash, and hydroxyproline and for sensory analysis. The breed of sire significantly affected pH 24 and 48 h postmortem, EC 24 h postmortem, protein content and juiciness (P < 0.05). Significant negative correlations between pH₄₈ and DM (− 0.255) and pH₄₈ and IMF (− 0.258) were found (P < 0.05). A significant positive correlation between EC₄₈ and drip loss (0.366) was observed (P < 0.05). Progeny of Charollais sires had meat of better quality than the others; the highest content of protein and IMF, the lowest drip loss and the best juiciness and texture.     

Influence of genetic type and level of concentrate in the finishing diet on carcass and meat quality traits in beef heifers

Carcass and meat quality traits of thirty-six feedlot beef heifers from different genetic groups (GG) fed at two concentrate levels (CL) were evaluated using 12 - Nellore (NE), 12 - ½Angus x ½Nellore (AN) and 12 - ½Simmental x ½Nellore (SN) animals. Six heifers of each GG were randomly assigned into one of two treatments: concentrate at 0.8% or 1.2% of body weight (BW). Heifers fed concentrate at 0.8% of BW had greater (P < 0.05) dressing percentage. None of the proximate analysis components of the beef were affected (P > 0.05) by either CL or GG. Heifers from the AN group had higher (P < 0.05) carcass weights, 12th rib fat thickness and lower dressing percentage (P < 0.05) compared to the other groups. NE heifers had greater WBSF values (P < 0.05) than the other genetic groups. Data suggest that the concentrate level can be reduced without compromising meat quality traits.     

Carcass and meat palatability breed differences and heterosis effects in an Angus-Brahman multibreed population

Additive genetic Angus-Brahman differences, heterosis effects, and least squares means for six carcass and six meat palatability traits were estimated using data from 1367 steers from the Angus-Brahman multibreed herd of the University of Florida collected from 1989 to 2009. Brahman carcasses had higher dressing percent (P < 0.0001), lower marbling (P < 0.0001), smaller ribeye area (P < 0.0001), and less fat over the ribeye (P < 0.0001) than Angus carcasses. Brahman beef was less tender (P < 0.0001), had more connective tissue (P < 0.0001), and it was less juicy (P < 0.001) than Angus beef. Heterosis increased hot carcass weight (P < 0.0001), dressing percent (P < 0.017), ribeye area (P < 0.0001), fat over the ribeye (P < 0.0001), and kidney, pelvic, and heart fat (P < 0.01) in Angus-Brahman crossbred steers. Results indicated that crossbred animals with up to 50% Brahman showed limited negative impact on meat quality while maximizing meat yield due to heterosis.     

Effect of exposure to light on physico-chemical quality attributes of sliced dry-cured Iberian ham under different packaging systems

Dry-cured Iberian ham slices were stored under vacuum and under two different atmospheres (N₂ = 70% N₂ + 30% CO₂; Ar = 70% Ar + 30% CO₂) and exposed to lightness or darkness. Physico-chemical, sensory and microbial analysis was carried out throughout 60 days storage. Vacuum samples showed the highest a*-value compared to N₂ and Ar after 30 (P < 0.05) and 60 days (P < 0.05). The influence of illumination during storage was evident after 60 days of storage, L* and a*-values being lower (P < 0.01) in hams exposed to light than those kept in darkness, which can be ascribed to the lower nitrosylmioglobin content in samples exposed to light after 60 days (P = 0.001). Ham slices stored in darkness showed the lowest TBARS values (P < 0.05) and hexanal content (P < 0.05) after 60 days. Slices of ham packed in vacuum showed lower TBARS values than N₂ and Ar batches (P = 0.001), these samples being perceived as more rancid (P < 0.05). The rest of the sensory attributes were not generally affected by gas mixture or illumination (P > 0.05).     

Color-stabilizing effect of lactate on ground beef is packaging-dependent

Previous research on lactate-induced color stability in ground beef did not address the potential influence of packaging. The objective of the present study was to examine the effects of lactate on the color stability of ground beef patties stored in different modified atmosphere packaging (MAP) systems. Ground beef patties with either 2.5% potassium lactate or no lactate were packaged in vacuum (VP), high-oxygen MAP (HIOX; 80% O₂ + 20% CO₂), carbon monoxide MAP (CO; 0.4% CO + 19.6% CO₂ + 80% N₂), or aerobic packaging (PVC) and stored for 0, 2, or 4 days at 2 °C. Lactate-treated patties were darker (P < 0.05; lower L∗ values) than control patties. Surface redness (a∗ values) was greater (P < 0.05) for lactate patties than the controls when stored in PVC, HIOX, and VP. However, lactate’s effects on a∗ values were not evident when packaged in CO (P > 0.05). The color-stabilizing effect of CO could have masked lactate’s effect on surface redness. While lactate patties in PVC and VP demonstrated lower (P < 0.05) discoloration than controls, no differences (P > 0.05) existed between controls and lactate samples in CO and HIOX. Our results indicated that the effects of lactate on ground beef color are dependent on packaging.     

Protein denaturing conditions in beef deep semimembranosus muscle results in limited μ-calpain activation and protein degradation

The objective was to determine the effect of muscle location on protein solubility and protein degradation in deep (DSM) and superficial (SSM) portion of beef semimembranosus. At 24 h postmortem, the semimembranosus was removed from beef carcasses (n = 10), packaged in high-oxygen modified atmosphere (80% O₂ + 20% CO₂), and displayed for 7 d at 1 °C. DSM had higher (P < 0.05) L*, a*, b*, and hue values than SSM throughout display. DSM had significantly higher protein denaturation and less protein concentration than SSM. Western blotting for μ-calpain autolysis revealed that DSM maintained more (P < 0.05) unautolyzed μ-calpain than SSM. This result coincided with less desmin and troponin-T degradation in samples from the DSM. These results confirm the hypothesis that increased protein denaturation in DSM results in minimal proteolysis by negatively affecting μ-calpain activation. This demonstrates a potential to alter progression of proteolysis and improvement in tenderness associated with postmortem storage.     

Effect of enriched housing on welfare,production performance and meat quality in finishing lambs: The use of feeder ramps

This study analyses the effect of environmental enrichment on the welfare, productive traits and meat quality of lambs housed in feedlots. Sixty lambs were placed in enriched (EE) or conventional (CO) pens (3 pens for each treatment, 10 lambs/pen) where EE had a wooden platform with ramps that provided access to a concentrate hopper, cereal straw as bedding and forage, and one play ramp. The CO pen was barren, similar to commercial feedlots. The physiological adaptation response of EE lambs was more efficient than CO, since the latter mobilised more body reserves (i.e., increased NEFA, P < 0.05), and had lower levels of immunity (i.e., increased N/L, P < 0.05), which indicate chronic stress, probably associated with the barren environment. The EE lambs had a higher (P < 0.05) average daily gain, with heavier carcasses and higher fattening scores, as well as lower pH_ult, higher L* and b* values, and lower values of texture (P < 0.05).     

Polymorphism and parent-of-origin effects on gene expression of CAST, leptin and DGAT1 in cattle

This study aimed to investigate differential allele expression (DAE) and polymorphism and parent-of-origin effects on expression of genes related to beef traits. CAST, related to meat tenderness, and DGAT1 and leptin, related to fat deposition, were evaluated. In bovine fetal tissues CAST was expressed twice as much (P < 0.05) in muscle of homozygous GG than in heterozygous AG. Leptin was expressed about one-tenth as much (P < 0.05) in heterozygous TpCm (allele T of paternal origin and allele C of maternal origin) than in homozygous CC. No DAE was observed. The evidence of polymorphism effect on expression of CAST and parent-of-origin effect on leptin contributes to a better understanding of events controlling the expression of genes of economic interest in cattle. Furthermore, if the parent-of-origin effects observed in fetal tissues are confirmed in adult tissues and associated to phenotypic variation, this parental origin criterion may be considered in marker-assisted selection of beef traits.     

The "sponge effect" hypothesis: an alternative explanation of the improvement in the waterholding capacity of meat with ageing

Bovine M. semimembranosus from different sexes of cattle were held at temperatures ranging from 0 to 35 °C until rigor and aged for up to 9 weeks. The waterholding capacity (WHC) of the beef increased with ageing as evidenced by the decline in drip loss measured gravimetrically, centrifugally and by pressure. Drip viscosity (P < 0.01), meat protein extractability (P < 0.05), spreadability (P < 0.01) and compressibility also increased with ageing. Evidence of structural changes was seen in SDS-PAGE confirming the physical changes. Meat spreadability under pressure and WHC were higher in samples with inherently higher pH relative to lower pH. The outcome of this study supports a hypothesis that the increase in WHC with ageing is due to the breakdown in meat structure and the creation of “sponge effect”, which disrupts the channels through which moisture is lost and physically entraps the free water in meat and reduce the amount that drips out.     

Effects of different lairage times after long distance transportation on carcass and meat quality characteristics of Hungarian Simmental bulls

The objective of this study was to determine the effects of three lairage times (24 h, 48 h and 72 h) on the meat quality of tame trained to lead Hungarian Simmental bulls subjected to long commercial transportation of approximately 1800 km. A total of 30 bulls, with an average age of 24 months, were used. During the lairage, bulls received 0.5 kg concentrate feed per animal per day and ad libitum access to the hay and water. As the lairage duration increased, the pH_ult decreased (P < 0.05). Bulls lairaged for 24 h had lower L*, b* and H* values than those lairaged for 48 h and 72 h (P < 0.05). The effect of lairage time on WHC, cooking loss and Warner–Bratzler shear force values was not significant. The b* value was considered the best predictor of muscle pH_ult. In conclusion, 72 h quiet lairage time is recommended after transportation in order to prevent the adverse effects of transportation on meat quality.     

Dietary lecithin improves dressing percentage and decreases chewiness in the longissimus muscle in finisher gilts

The influence of dietary lecithin at doses of 0, 4, 20 or 80 g/kg fed to finisher gilts for six weeks prior to slaughter on growth performance, carcass quality and pork quality was investigated. M. longissimus lumborum (loin) was removed from 36 pig carcasses at 24 h post-mortem for Warner–Bratzler shear force, compression, collagen content and colour analyses. Dietary lecithin increased dressing percentage (P = 0.009). Pork chewiness and collagen content were decreased by dietary lecithin (P < 0.05, respectively), suggesting that improved chewiness may be due to decreased collagen content. However, dietary lecithin had no effect on shear force, cohesiveness or hardness (P > 0.05, respectively). Dietary lecithin reduced loin muscle L* values and increased a* values (P < 0.05, respectively) but no changes on b* values (P = 0.56). The data showed that dietary lecithin improved dressing percentage and resulted in less chewy and less pale pork.     

Effect of varying the gas headspace to meat ratio on the quality and shelf-life of beef steaks packaged in high oxygen modified atmosphere packs

Beef steaks (M. longissimus dorsi) were stored in modified atmosphere packs (MAP) (80% O₂:20% CO₂) with gas headspace to meat ratios of 2:1, 1:1 and 0.5:1 for 14 days at 4 °C. The pH, surface colour, texture and microbiology of beef steaks were unaffected (P > 0.05) by varying the gas headspace to meat ratio. APLSR (ANOVA-partial least squares regression) and jack-knife uncertainty testing indicated that lipid oxidation (TBARS) was significantly positively correlated with days 10 (P < 0.05) and 14 (P < 0.001) of storage. Chemical and sensory detection of lipid oxidation in beef steaks were in agreement on day 14 of storage. The sensory quality and acceptability of beef steaks were similar in gas headspace to meat ratios of 2:1 or 1:1 and unacceptable in 0.5:1. Results indicate that pack size and gas volume can be reduced without negatively affecting fresh beef quality and shelf-life.     

Small heat shock protein degradation could be an indicator of the extent of myofibrillar protein degradation

The objective of the present study was to evaluate the relationship between small heat shock proteins (sHSP) degradation and tenderness development of beef loins at different ultimate pH (pH_u). A total of twelve loins (M. longissimus dorsi) from steers were obtained at 1 day post mortem. Shear force and proteolysis of each loin were analyzed at 1 and 28 days post mortem. The loins at intermediate pH_u (5.8 to 6.0) showed more variation in tenderness compared to the loins at low pH_u (< 5.8), where few samples were still tough (> 10 kgF) at 28 days. The intact sHSP20 was more pronounced (P < 0.05) in the intermediate pH_u loin compared to the low pH_u counterpart. Further, high correlations between the degradation of both sHSP and myofibrillar proteins were observed (e.g. r = 0.94; degraded sHSP27 and degraded desmin). The result of this study suggests that the extent of sHSP degradation could be an indicator of myofibrillar protein degradation and tenderness.     

Enhancing pork loin quality attributes through genotype,chilling method and ageing time

The experiment was conducted to examine opportunities for enhancing pork quality through the use of post-mortem ageing when combined with different chilling regimes. Large White (LW, n = 24) and Duroc × Large White (Duroc, n = 24) barrows were slaughtered and alternate carcass sides were either conventionally or blast-chilled. The longissimus thoracis et lumborum muscle was dissected from the carcass sides (24 h post-mortem) and trimmed of cover fat. Three sections (15 cm length) were vacuum packaged and assigned to 2, 7 or 14 days of ageing (2 °C) randomized within muscle location. Blast-chilled meat had lower purge (P = 0.009) and drip (P = 0.0009) losses and higher hue (P = 0.02) than conventionally chilled meat. However chilling by conventional or blast-chilling methods had no effect on sensory characteristics (P > 0.1). When breeds were compared, meat from Duroc barrows had lower moisture (P < 0.0001) and higher intramuscular fat content (P < 0.0001), L∗ (P = 0.0003) and hue (P = 0.007) values than LW. Overall tenderness (P = 0.005), juiciness (P = 0.0007) and palatability (P < 0.0001), as well as flavour intensity (P < 0.0001) and desirability (P < 0.0001) values were higher and undesirable flavours were lower (P < 0.0001) for meat from Duroc pigs, when compared with LW. Ageing increased purge loss (P < 0.0001), L∗ (P < 0.0001), hue (P < 0.0001), chroma (P < 0.0001) and content of protein (P = 0.002), with corresponding decreases (P < 0.0001) in drip loss and moisture content. Instrumental (P < 0.0001) and sensory (initial, P < 0.0001 and overall, P < 0.0001) tenderness increased from day 2 to 14. Therefore independent of chilling method, ageing improved quality of pork loins. Moreover ageing had greater effect on tenderness, while breed had greater effect on flavour which may be related to differences in intramuscular fat content.     

Carcass and meat quality characteristics and fatty acid composition of tissues from Pietrain-crossed barrows and gilts fed an elevated monounsaturated fat diet

Fifty-one (Landrace∗Large White)∗Pietrain barrows and gilts were used to compare the effect of a diet rich in oleic acid (HO) by feeding a by-product of the olive industry (Greedy-Grass OLIVA®: 1.4% growing, 3.8% finishing) or a grain and soy diet (CONTROL) on carcass characteristics, meat quality and fatty acid profile of intramuscular and subcutaneous fat. Gilts had leaner (P < 0.05) carcasses with lower fat percentage in major primal cuts, and less (P < 0.05) saturated fat compared with barrows with no interaction (P > 0.05) between dietary treatment and gender. Source of dietary fat had no effect (P > 0.05) on primal cut yields, composition of major primal cuts, or carcass and meat quality characteristics. Intramuscular fat from HO fed pigs had higher (P < 0.05) percentage of saturated (SFA) and monounsaturated (MUFA) fatty acids, and lower (P < 0.05) polyunsaturated fatty acids (PUFA) and n-6:n-3 ratio compared with CONTROL animals (37.4% vs. 36.8%, 44.7% vs. 40.1%, 17.9% vs. 23.2%, and 18.9 vs. 21.8 ratio, respectively). Subcutaneous fat from pigs fed HO had greater (P < 0.05) MUFA percentage, lower (P < 0.05) SFA and PUFA percentage, and lower (P < 0.05) n-6:n-3 ratio than pigs fed CONTROL diet (51.4% vs. 48.0%, 30.5% vs. 32.9%, 18.1% vs. 20.1%, and 9.83 vs. 11.3 ratio, respectively). Intramuscular fat had higher proportion of SFA and lower of MUFA showing a higher degree of tissue saturation compared with subcutaneous fat. Feeding Greedy-Grass increased MUFA and decreased PUFA proportions in fat depots reducing the risk of production of carcasses that are soft and oily which result in lower technological and processing quality.