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Background Carcass evaluation is a key process to ascertain the value and the quality characteristics of the animal at slaughter. In addition to being the base for monetary transactions between livestock producers and meat processors, in some countries, this evaluation also helps to determine the market allocation of cuts. Recent advances in non-invasive techniques are being tested for their potential to improve classification and grading systems in the meat industry. Scope and approach In this review, global grading and classification practices for pig, sheep and beef carcasses are discussed along with the latest technological developments in objective carcass measurement. We discuss a number of studies predicting marketable attributes such as yield (lean and saleable meat yield), eating quality attributes (inter- and intra-muscular fat, meat and fat colour) and carcass dimensions (skeletal structure, ribeye area). Technologies based on x-ray, nuclear magnetic resonance, video image analysis, ultrasound, bioelectric impedance and spectroscopy are discussed, along with recent developments and their possible future adoption. Key findings and conclusions Dual-energy x-ray absorptiometry and magnetic induction technologies have been commercialised for the sheep and pig industries, respectively. X-ray technologies and updates in video image analysis could go beyond grading to improve yield and cut dimension predictions. Some technologies could improve process efficiencies through cut sorting and enabling robotic cutting, while also enabling improved value-based payment systems. However, there are challenges associated with their implementation in meat processing plants and further research and development is required in some areas.

Meat consumption internationally is driven by many common factors. While this broadly results in similar temporal trends, diversity in how these factors play out locally is evident. Drawing on secondary data sources, this paper illustrates this by comparing Irish meat consumption with other geographies. It illuminates the differential impact of significant shocks, e.g. the BSE crises, and socio-cultural factors on consumption. With increased attention on sustainability, how motivations relating to health, the environment and animal welfare will influence consumption is likely to vary across countries. Questions arise as to how strategies such as "less but better" will evolve, with available options including changing production parameters, producing meat-blended products, premiumisation and meat reduction. Given that the demand for meat stems as much from its traditional role in cultural practices as it does from satisfying individual needs, the extent to which consumer needs are being met by current offerings will change as the position held by meat in society changes.

New and emerging robust technologies can play an important role in ensuring a more resilient meat value chain and satisfying consumer demands and needs. This paper outlines various novel thermal and non-thermal technologies which have shown potential for meat processing applications. A number of process analytical techniques which have shown potential for rapid, real-time assessment of meat quality are also discussed. The commercial uptake and consumer acceptance of novel technologies in meat processing have been subjects of great interest over the past decade. Consumer focus group studies have shown that consumer expectations and liking for novel technologies, applicable to meat processing applications, vary significantly. This overview also highlights the necessity for meat processors to address consumer risk-benefit perceptions, knowledge and trust in order to be commercially successful in the application of novel technologies within the meat sector.

This study evaluated the contributions of sensory traits to overall liking in Europe. Perceptions by untrained consumers of tenderness, juiciness, flavor liking and overall liking were determined using the Meat Standards Australia protocols. According to European consumer testing with European beef samples, flavor liking was the most important contributor (39%) to beef overall liking, followed by tenderness (31%) and juiciness (24%) (P0.94). The improvement in tenderness over the last decades may explain the highest contribution of flavor liking nowadays. Flavor liking is therefore the main driver of variability in overall liking. Juiciness is the least robust trait which could be influenced by other traits during consumer perception. For outstanding steaks, each sensory trait should have excellent scores and high contributions to overall liking. For medium cuts, one sensory trait with a low score has the potential to be compensated by other traits with higher scores and more emphasis will be placed on the trait with the lowest perception.

The ability of brown seaweed extracts, Ascophyllum nodosum, Laminaria hyperborea, Pelvetia canaliculata, Fucus vesiculosus and Fucus serratus to protect against tert-butyl hydroperoxide (tert-BOOH) induced stress in Caco-2 cells was investigated. Oxidative stress was determined by measuring alteration in the enzymatic activity of catalase (CAT) and superoxide dismutases (SOD) and cellular levels of glutathione (GSH). L. hyperborea, P. canaliculata and F. serratus significantly protected against tert-BOOH induced SOD reduction but did not protect against the reduction in CAT activity or the increased cellular levels of GSH. The ability of F. serratus and F. vesiculosus to protect against H(2)O(2) and tert-BOOH induced DNA damage was also assessed. The DNA protective effects of the two seaweed extracts was compared to those of three metal chelators; deferoxamine mesylate (DFO), 1,10-phenanthroline (o-phen) and 1,2-Bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid tetrakis (BAPTA-AM). F. serratus and F. vesiculosus significantly protected (P

To examine the effect of a modification of a typically Irish dairy calf-to-beef production system, Charolais × Friesian steers were offered a finishing ration of grass silage ad libitum and 5.6 kg concentrates daily for 174 days prior to slaughter at 25 months of age or grass silage ad libitum for 174 days, followed by pasture for 167 days and slaughter at 30 months of age. Finishing at pasture increased carcass weight (376 vs. 342 kg) but did not affect intra-muscular lipid concentration (28 vs. 24 g/kg). Finishing at pasture decreased Longissimus thoracis et lumborum lightness (35.6 vs. 36.9) and increased shear force of muscle at 2 (8.54 vs 4.32) and 7 days (5.21 vs 3.64 kg) post-mortem but not at 14 days post-mortem (4.45 vs. 3.42 kg). Finishing at pasture did not affect the sensory characteristics of tenderness, juiciness, firmness or chewiness and tended (P

The antioxidant potential of methanolic extracts of brown seaweeds was assessed by Total Phenol Content, Ferric Reducing Antioxidant Power (FRAP), β-carotene bleaching and the DPPH scavenging assays. Ascophyllum nodosum, Pelvetia canaliculata, and Fucus serratus contained the highest phenol concentrations while Fucus vesiculosus and F. serratus exhibited the highest FRAP activities. F. vesiculosus and A. nodosum were the most effective extracts at scavenging DPPH radicals and preventing β-carotene bleaching. The antioxidant activity of the seaweed extracts was also evaluated in Caco-2 cells. All extracts significantly (P

The effectiveness of increasing CLA in pork products through animal dietary supplementation or direct addition in the product formulation has been studied, and the effect of grilling on dry matter and fat contents and fatty acid composition has been analysed. Sausages made with meat and back fat from pigs with CLA dietary supplementation had the highest saturated fatty acid content. Sausages from dietary supplementation and direct addition had CLA levels between 6% and 7% of total fatty acids. Moisture and fat contents decreased and increased respectively after cooking for the three sausage types (control, dietary supplementation, direct addition). Grilling had little effect on fatty acid levels, especially for sausages with direct addition in the product formulation. In general, saturated fatty acids increased and poly-unsaturated fatty acids decreased due to the increase of C16:0 and to the decrease of C18:2 n 6c and C18:3 n 3 fatty acids. Added CLA, both from animal dietary supplementation or direct addition, remained at similar levels in cooked sausages to those found in raw sausages.

Approaches for improving the profile of functional unsaturated fatty acids in pork products include dietary supplementation of pigs with functional oils. Little information is available to indicate the benefit of this approach in a processed and cooked pork product such as breakfast sausages. Therefore, the aim of the present study is to examine the fatty acid profile and oxidation level in cooked pork sausages, produced following dietary supplementation with CLA compared to sunflower oil (SFO). Fat and moisture percentages, total fatty acid profiles and TBARS were analysed. Fatty acid profiles were altered in the sausages following all treatments. While a stronger effect was seen for CLA treatments, addition of SFO in the diet also resulted in linear increases of CLA in the sausages. CLA supplementation resulted in increased saturated fatty acid content; however, all treatments were within the recommended polyunsaturated/ saturated fatty acid ratio of above 0.4. Improved oxidative stability was observed in sausages from CLA supplemented diets.

Longissimus dorsi (LD) muscle from 60 Charolais crossbred heifers, aged for 14 days was used to investigate the effect of cooking on the content of PUFA and CLA fatty acids. Animals were offered a control diet of grass silage and concentrates (CO) or rations designed to enhance the concentration of CLA in tissue, i.e. unsupplemented grazed pasture (G), sunflower-oil supplemented grazing (SFG) or linseed-oil oil supplemented grazing (LSG). The SFG diet was the most effective for increasing the concentration of CLA but also caused the highest n −6/ n −3 fatty acid ratio. There were no changes in the relative distribution of fatty acids upon cooking (140 °C for 30 min) and this procedure can be recommended because it preserves the nutritional value of the meat. It is concluded that irrespective of the change in the fatty acid composition of LD due to alteration in the diet of the cattle, cooking did not cause thermal degradation of PUFA, or thermal degradation or oxidative synthesis of CLA.

Connective tissue of three porcine muscles (M. infraspinatus, IS; M. longissimus dorsi, LD; M. semimembranosus, SM) from 27 animals [populations A (n = 13, reared in Ireland) and B (n = 14, reared in Finland)] was studied by measuring the collagen content, collagen solubility and thermal shrinkage temperature of the connective tissue. Colour and pH were also determined. Collagen solubility was highest in IS (p < 0.05) and lowest in SM (p < 0.05) although no difference between LD and SM was found in population B. The onset and peak temperatures of thermal shrinkage (To and Tp) were highest in IS (p < 0.05). The lowest To and Tp were found in SM from population B whereas no differences were seen between LD and SM muscles in population A. It was concluded that the thermal stability of the connective tissue in the three porcine muscles differ. IS, as a dark muscle has high thermal shrinkage temperatures and high collagen solubilities in comparison to the lighter LD and SM muscles which have lower thermal shrinkage temperatures and collagen solubilities. Collagen contents were highest in IS and lowest in LD.

The objective of this study was to evaluate the importance of proteolysis and sarcomere length in determining the tenderness of bovine M. longissimus dorsi (LD) muscle over a 21-day period. This was done by altering the pre-rigor glycolytic behaviour of hot-boned LD muscles using different early post-mortem temperature regimes. Hot-boned LD muscles (n=8) were cut in two, randomised, placed in polythene bags and submerged in a water bath set at 5°C (rapidly chilled) and 15°C (slowly chilled) for 8h post-mortem. All muscles were then stored at 2°C for up to 21 days post-mortem. The temperature regimes altered the glycolytic behaviour of the muscles in the pre-rigor period. The slowly chilled muscles exhibited a faster (P0.01) pH fall than rapidly chilled muscles. Cold shortening was induced in rapidly chilled muscles as they had shorter (P0.01) sarcomere lengths than slowly chilled muscles up to day 21 post-mortem. Warner Bratzler shear force values (WBSF) deemed cold-shortened muscles as tougher than noncold shortened up to day 14 post-mortem. Both cold-shortened and noncold-shortened muscles tenderised over time to an extent where there was no significant difference in WBSF values by day 21 post-mortem. SDS-PAGE protein profiles indicated that the rate of proteolysis was faster in slowly chilled muscles when compared to rapidly chilled muscles. However by day 21 post-mortem it appeared that rapidly and slowly chilled muscles underwent proteolysis to the same extent.

The effect of supplementation of beef cattle diets with tea catechins (TC) (1000mg/animal/day) and rosemary extract (RE) (1000mg/animal/day), for 103 days preceding slaughter, on the oxidative stability of M. longissimus dorsi (LD) steaks was evaluated. Dietary supplementation with TC and RE did not increase plasma total antioxidant status (TAS), LD α-tocopherol concentrations or pH. In LD steaks stored aerobically or in modified atmosphere packs (80% O(2):20% CO(2)) (MAP) for up to 8 days at 4°C, surface redness (CIE 'a' redness value) and lipid stability (TBARS, mg MDA (malondialdehyde)/kg muscle) were not significantly improved as a result of supplementation with TC and RE. Similarly no improvement in the sensory properties and lipid stability of cooked LD slices, stored aerobically or in 30% CO(2):70% N(2) for up to 11 days at 4°C, was observed. An in vitro fermentation study demonstrated that TC and RE were not fermented to any great extent under simulated rumen conditions. Direct addition of TC (1000ppm) and RE (1000ppm) significantly (P

The influence of breed and mh -genotype on carcass conformation, meat physico-chemical characteristics and the fatty acid profile of muscle were studied. Samples from 16 yearling bulls from “Asturiana de los Valles” (AV, n = 12) and “Asturiana de la Montana” (AM, n = 4) were collected. AV animals were classified into three groups according to the presence of the gene causing double-muscling (AV double-muscled ( mh/mh ), n = 4; AV heterozygous ( mh /+), n = 4; AV normal (+/+), n = 4). Double-muscled animals displayed better carcass traits, lower total fat (comprised of subcutaneous (SC), intermuscular (IT) and intramuscular (IM) deposits), higher lean, moisture and drip loss, and lighter meat than AV normal animals. Heterozygous animals showed intermediate characteristics. AM animals, being a more rustic and smaller breed, showed lower conformation, higher total fat (SC, IT and IM), lower moisture and darker meat. According to the intramuscular fatty acid profile, mh / mh animals showed a lower proportion of SFA and MUFA, and a higher proportion of PUFA with an equal proportion of CLA in total fatty acid content. The P/S ratio increased with increasing number of mh alleles (or double-muscling character), while no differences between animal groups were found for the n − 6/ n − 3 ratio.

Pork loins were pumped to 110% of original weight with solutions containing 5.5% salt and 3.3% sodium tripolyphosphate, 5.5% salt and 3.3% β-lactoglobulin (β-lg) enriched fraction or 5.5% salt and 3.3% whey protein concentrate 80% (WPC80) for comparison with non-enhanced control loins. The enhancement of pork loins significantly increased (p

This study characterised the lipid classes of Longissimus dorsi (LD) muscle and the fatty acid profiles of the LD intramuscular fat and subcutaneous (SC) adipose tissue of male and female foal mixed populations. Two animal groups were studied based on slaughter ages of 16 and 24 months. The sex of the animals had no statistical significance in the lipid fractions of the LD muscle or in the intramuscular fatty acids (p⩾0.05). In contrast, there was a significant effect of sex on the fatty acid profile of the SC adipose tissue. Furthermore, the livestock production system showed difference in both lipid class and fatty acid profiles from the LD and SC adipose tissues. The LD of 24-month old foals had lower phospholipids content (p⩽0.001), displayed little difference in saturated fatty acids (SFA) (p⩽0.1), exhibited higher levels of monounsaturated fatty acids (MUFA) (p⩽0.05) and lower levels of polyunsaturated fatty acids (PUFA) (p⩽0.05) compared with that of the 16-month old foals. Furthermore, the fatty acid profile of the SC adipose tissue of the 24-month old foals had higher SFA (p⩽0.05) and PUFA (p⩽0.01) with lower amounts of MUFA (p⩽0.001) relative to the 16-month old foals.

The darker coloured meat sometimes reported when cattle finished at pasture are compared to cattle finished indoors may reflect breed, diet, age at slaughter, exercise and/or environment. To determine the contribution of exercise/environment to beef colour, 24, 24-week-old Holstein/Friesian bulls were either housed (H, 2.5 m 2 /animal) or maintained at pasture (P, 133 m 2 /animal) for 180 days prior to slaughter. The bulls were offered a barley-based concentrate ad libitum and minimum roughage (straw for H and grass for P) to maintain rumen function. Changes in fat deposition were used as an index of exercise. Concentrate intake (group basis) was 7.0 and 6.5 kg dry matter for H and P, respectively. Mean carcass weight was 234 and 246 (sed 4.63) kg for H and P, respectively. Corresponding values for carcass fat score, kidney fat weight and longissimus thoracis (LT) muscle lipid concentration were 3.13 and 2.67 (sed 0.165), 17.9 and 13.9 (sed 2.08) g/kg carcass and 6.7 and 5.4 (sed 0.172) g/kg. Neither LT lightness (Hunter L value) at 2 (mean 35.5) or 7 days (mean 35.7) post-mortem, redness (Hunter a value) at 2 (mean 11.1) or 7 days (mean 13.8) post-mortem nor the pattern of pH fall post-mortem, differed between H and P. It is concluded that exercise/environment sufficient to alter body composition did not affect LT muscle colour in bulls.

Meat quality comparisons were carried out on hams produced from pork legs showing evidence of PSE and normal pork legs. Quality measurements included drip loss, sliceability, cooking loss, TBARS analysis and colour evaluation (Hunter L, a, b). A total of 40 pork legs were selected from a commercial slaughtering plant, 20 from carcasses showing PSE and 20 from normal carcasses based on L, a, b, and pH values. Carcass pH taken between the third/fourth rib was measured 45 min, 90 min, and 24 h after slaughter. Using a Minolta colorimeter (Hunter L, a, b,), colour of the Longissimus dorsi muscle was measured 24 h after slaughter. PSE had an adverse effect on cooked hams in comparison to normal cooked hams with respect to driploss (P

Heifers (n=10) were randomly selected from the slaughter line of a local factory each month for a period of 21 months. Rib steak (sampled at the 10th rib) from the left side of each carcass was taken for analysis. The cattle breeds selected during this study were Friesian, Hereford and Charolais. The mean weight of the left side for all carcasses was 146.6 (S.E.M.= 1.0kg). Graded carcasses selected for sampling during this trial were classified using the EUROP scale and the specific heifer grades chosen were factory grades EO4L and EO4H. Initial Hunter 'a' values (on the day of arrival in the laboratory) of rib steak from heifers finished between November and March (overwintered) were significantly (P0.001) higher than Hunter 'a' values from heifers finished between April and October (pastured). After storage at 4 °C under simulated retail display conditions for 6 days, the Hunter 'a' values for overwintered samples were also significantly (P0.001) greater than those for pastured samples. Breed also had an effect on the colour of the meat. After storage for 6 days, Hunter 'a' values of rib steak from Charolais were significantly (P0.05) higher than either Friesian or Hereford. Pastured heifers had significantly (P0.05) higher levels of the monounsaturated fatty acid C16.1 in the total lipid fraction of rib steak (neutral and polar) than samples taken from overwintered heifers. Pastured heifers had significantly (P0.01) higher levels of the polyunsaturated fatty acid (PUFA) C18.3 in the phospholipid fraction than those from overwintered cattle. However, Hereford had significantly (P0.05) higher levels of C14.0, C16.1 and C18.0 in the phospholipid fraction than those found in Friesian and Charolais. The level of α-tocopherol in the muscle was not affected by either pasturing/overwintering or breed. However, Continental breeds had significantly (P0.05) higher levels of α-tocopherol in adipose tissue than Friesian.

Meat products manufactured from low-value cuts may be unacceptably tough because of the high connective tissue content of meats used in their manufacture. The effects of shin beef treated with lactic acid at two concentrations (0.5 mol/L and 0.05 mol/L) and citric acid (0.05 mol/L) on cook loss, colour, textural and sensory characteristics of frankfurters were investigated. The results were compared to two controls containing high and low-value beef. Results indicate that the acids had little or no effect on cook loss and at the low concentrations had no apparent tenderising effect in comparison to the control shin beef. However, a significant effect on tenderness (P

A semi-quantitative SDS-PAGE method was standardised for the routine analysis of myofibrillar protein fragments, 30 and 110 kDa, associated with the meat tenderisation process. Bovine serum albumin was used as an internal standard. Standard curves for purified proteins demonstrated a linear response using this method. Mean analytical recoveries were 95.5 and 102.8% for separation on 7.5 and 15% acrylamide gels, respectively. The ability of the test to measure 30 kDa and 110 kDa fragments independently of sample volumes was demonstrated. Quality control studies showed that levels of 110 kDa protein fragment quantified on 7.5% gels varied by 23.1% within gels and 36.4% between gels. Quantification of 30 kDa protein fragment on 15% gels varied by 7.3% within gels and 7.0% between gels. This thoroughly standardised SDS-PAGE method may be used to measure 30 and 110 kDa bands in extracts of bovine M. longissimus dorsi over the post-mortem ageing period and to evaluate other quantitative methods developed in the future for measurement of the same protein fragments.

Hereford cross heifers ( n =3) were slaughtered and hung conventionally. At 1 h post-mortem the M. longissimus dorsi (LD) was excised, vacuum packaged in plastic bags and stored at 4°C. Samples were taken from each of eight different locations along the length of the LD muscle at 1 h, 1, 3 and 15 days post-mortem for extraction using 5% TCA. Supernatants were stored at −20°C until analysis by HPLC. Peptides produced during the storage of beef were isolated by high performance liquid chromatography (HPLC). Results show that these components increase in quantity from 1 h to 15 days post-mortem. Five fractions were collected which correspond to various peaks of interest. These fractions were subsequently analysed by mass spectrometry and amino acid sequencing to reveal their identity. Fractions 1 and 2 were found to be mixtures of low molecular components. Fractions 3, 4 and 5 were found to be proteolytic fragmentation products of glyceraldehyde-3-phosphate dehydrogenase, troponin T and creatine kinase, respectively. Enhanced appearance of proteolytic fragments from these parent proteins with muscle ageing suggest that they may be useful indicators of meat quality. Further work incorporating sensory and/or texture evaluation of muscle tissue is required to investigate this issue

Proteolysis of myofibrillar proteins results in an increase in substrate made available for the release of free amino acids. Levels of these amino acids have previously been determined in different muscles over the post mortem ageing period in beef. However, there is a shortage of information available regarding variations within a muscle over this ageing period. The objective of this study was to carry out preliminary investigations into the free amino acid levels in eight locations along the M. longissimus dorsi (LD) over the post mortem ageing period. Free amino acids were analysed in the LD of three Hereford cross heifers at 1 h, 1, 3 and 15 day post mortem. In general most amino acids increased in all locations over the ageing period while a 100% increase was observed in total amino acids averaged over the eight locations. More variations occurred between locations in the earlier post mortem period, however, there were no consistent differences during ageing which might suggest variations in proteolytic activity along the LD. As these analyses were carried out on three animals a larger number of animals would need to be sampled to verify these results.

The optimising of the composition of ingredients has a major effect on the properties of low-fat products. The purpose of this research was to assess the effects of added tapioca starch (ranging from 0–30 g/kg), oat fibre (ranging from 0–20 g/kg) and whey protein (ranging from 0–20 g/kg) on the physical and organoleptic characteristics of low-fat beef burgers. Response surface methodology (RSM) was used to study the simultaneous effects of these three ingredients. Significant models of regression were ascertained for cooking properties (yield and water holding capacity), the sensory attributes of tenderness and juiciness, and all mechanical texture attributes. The level of tapioca starch (TS) influenced the models to the greatest extent. Its effect on the cooking properties was highly significant, positive and linear. The presence of TS had a large negative linear effect on Warner-Bratzler and Kramer shear forces. For each significant regression model, TS exerted a linear effect, and in some cases a quadratic effect. Both oat fibre and whey protein had a limited influence. There was no evidence of interactions among the variables. The results indicate that as the TS in low-fat beef burgers increases a succulent and tender low-fat product is obtained.

Heifers (n = 70) were slaughtered and hung conventionally in an industrial meat plant. Near infrared (NIR) spectroscopy was studied for its ability to predict selected meat quality attributes, i.e. Warner-Bratzler shear force (WBSF), sensory tenderness, texture, flavour and acceptability. Freshly cut steaks (2.5 cm thick) were taken from the longissimus dorsi (LD) muscle at 1, 2, 7 and 14 days post mortem for NIR analysis. Other samples (also 2.5 cm thick) were taken at 2, 7 and 14 days post mortem, vacuum-packaged in plastic bags and stored at -20 °C for WBSF measurement and sensory analysis. Heifers were slaughtered in two groups; between slaughterings, replacement of the spectrophotometer lamp and lamp assembly was necessitated by a bulb failure. Using principal component regression (PCR), correlation coefficients of 0.82 and 0.73 were obtained for the prediction of WBSF in sample sets 1 and 2, respectively. On merging both sample sets, this value was lowered slightly (r = 0.61). Correlation coefficients obtained for the prediction of tenderness, texture, flavour and acceptability were 0.67, 0.53, 0.51 and 0.46 respectively (set 1); 0.72, 0.71, 0.45 and 0.67 (set 2); 0.53, 0.54, 0.24 and 0.42 (combined sets).

The effects of fat level (5% and 12%), tapioca starch and whey protein on the hydration/ binding properties, colour, textural and sensory characteristics of frankfurters were investigated. Decreasing the fat content increased cook loss and decreased emulsion stability and product lightness. Fat reduction increased smoke, spice and salt intensities and increased overall flavour intensity and juiciness. Texture profile analysis (TPA) indicated that fat reduction decreased gumminess and cohesiveness but the other parameters measured were unaffected. Addition of tapioca starch or whey protein reduced cook loss and increased emulsion stability. Whey protein did not effect the sensory characteristics but tapioca starch increased overall flavour intensity. Both ingredients increased hardness, adhesiveness, gumminess and chewiness as measured by TPA. Two-factor interactions between fat level and ingredient were observed for several parameters. The results indicate that both ingredients can partially offset some of the changes which occur in low-fat frankfurters when fat is replaced with added water and protein level is constant.