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Enhancing transparency through the beef production supply chain using objective measurements is crucial for maintaining the premium price of Australian beef products. A four-class model has been developed using Raman spectroscopy for beef cattle sourced from four different production systems including long- and short-term grain-fed and grass- and grass-supplemented-fed cattle with an F1 score of 92%, 88%, 98% and 100%, respectively. A two-class model for grain- and grass-fed cattle showed 98.5% and 97.1% correct classification. Both models were developed using a dataset of 404 calibration samples and 101 test samples which resulted in a total of 6 and 2 misclassified samples in the four- and two-class models, respectively. Fatty acids were also utilised to separate samples by principal component analysis (PCA), and loadings revealed samples that could be separated by the concentration of omega-3 polyunsaturated fatty acids. A discriminant analysis of fatty acid data yielded a classification accuracy of between 88 and 100% of beef carcases according to production system. Thus, classification utilising Raman spectroscopy provided a reliable method to discriminate between cattle finished by different feeding systems. [ABSTRACT FROM AUTHOR]

The use of total volatile basic nitrogen (TVB‐N) as a quality parameter for fish is rapidly growing to include other types of meat. Investigations of meat quality have recently focused on TVB‐N as an index of freshness, but little is known on the biochemical pathways involved in its generation. Furthermore, TVB‐N and methylated amines have been reported to exert deterimental health effects, but the relationship between these compounds and human health has not been critically reviewed. Here, literature on the formative pathways of TVB‐N has been reviewed in depth. The association of methylated amines and human health has been critically evaluated. Interventions to mitigate the effects of TVB‐N on human health are discussed. TVB‐N levels in meat can be influenced by the diet of an animal, which calls for careful consideration when using TVB‐N thresholds for regulatory purposes. Bacterial contamination and temperature abuse contribute to significant levels of post‐mortem TVB‐N increases. Therefore, controlling spoilage factors through a good level of hygiene during processing and preservation techniques may contribute to a substantial reduction of TVB‐N. Trimethylamine (TMA) constitutes a significant part of TVB‐N. TMA and trimethylamine oxide (TMA‐N‐O) have been related to the pathogenesis of noncommunicable diseases, including atherosclerosis, cancers, and diabetes. Proposed methods for mitigation of TMA and TMA‐N‐O accumulation are discussed, which include a reduction in their daily dietary intake, control of internal production pathways by targeting gut microbiota, and inhibition of flavin monooxygenase 3 enzymes. The levels of TMA and TMA‐N‐O have significant health effects, and this should, therefore, be considered when evaluating meat quality and acceptability. Agreed international values for TVB‐N and TMA in meat products are required. The role of feed, gut microbiota, and translocation of methylated amines to muscles in farmed animals requires further investigation. [ABSTRACT FROM AUTHOR]

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Specific for lamb, this study aimed to test the effect of Nix Pro Color Sensor (NIX) repeat measures on the precision of L*, a*, b*, hue and Chroma (colour traits); compare colour traits captured using the NIX and HunterLab MiniScan (HUNTER) instruments; and establish the impact of NIX settings (Illuminant and standard observer) on retail colour stability. This used the longissimus lumborum muscles from the right-side of 150 Merino carcasses were sampled and then aged in vacuo for 5 days. It was found that six repeat measures were appropriate in general to achieve precise colour data for lamb meat. Observed colour trends over retail display were analogous, but not interchangeable between NIX and HUNTER instruments—except for a* data which was comparable between instruments. Only b* and hue were found to be impacted by NIX Illuminant and standard observer settings, and Illuminant A captured the greatest magnitude change in b* over retail display. These findings support the reproducible and robust assessment of lamb meat colour using the NIX. [ABSTRACT FROM AUTHOR]

Although Norway is the largest sheep meat producer in Scandinavia and Norwegian Muslims are expected to double in population in the next decade, the overall local per capita red meat consumption is still low. Meanwhile, Norwegian Muslims' purchasing preferences on lamb meat products have not been investigated. This paper presents the results of a choice-based conjoint survey which would help stakeholders to understand the niche Muslim immigrant halal meat market and potentially increase meat consumption. Post-hoc market segmentation was performed using latent class analysis, and factors affecting consumers' purchase intentions were studied within each segment. Results show that purchasing halal meat from a butcher was the top preference while there was a higher willingness to purchase from national supermarkets among younger second-generation Pakistanis. In order to benefit from niche halal meat market, Norwegian supermarkets are recommended to adapt some of the services that halal butchers are offering to their consumers. [ABSTRACT FROM AUTHOR]

This study evaluated the effects of low doses of gamma radiation (up to 2.0 kGy) on the survival and growth of Listeria monocytogenes and on technological characteristics of RTE cooked hams, formulated without and with 50 and 150 mg/kg of sodium nitrite, after 30 days of cold (4°C) storage. The radiation reduced from 0.33 kGy in uncured and RTE50 to 0.25 kGy in RTE150 and after storage, a reduction (p >.05) in the Listeria growth in the cured samples. Irradiation had no effect (p >.05) on the pH, water activity, residual nitrite, lipid oxidation, or CIELCH color indices of RTE hams, regardless of the nitrite content. Higher TBARS values, chroma, and hue angle were observed (p <.05) in uncured samples than in cured ones. The RTE50 with irradiation by 1.0 to 2.0 kGy can be used to ensure the Listeria safety. Practical applications: Meat RTE products post‐thermal manipulation, like in slicing operations, may result in an enhanced microbial risk, especially regard to Listeria postprocessing contamination. Therefore, post‐lethality treatments like gamma irradiation are of interest to the industry to ensure food safety. Combining the lower doses of irradiation with low nitrite content in RTE meats could be used to guarantee microbial safety, minimizing irradiation‐induced quality changes, and contributing to the sensory and technological characteristics of the products. [ABSTRACT FROM AUTHOR]

Objective: This study was aimed to investigate the muscle-specific beef color stability at normal and high ultimate pHs. Methods: The impact of muscle (Longissimus lumborum [LL] vs psoas major [PM]) and pH (normal ultimate pH [Np] vs high pH dark cutting beef [Hp]) on color stability, indicated by basic color traits, metmyoglobin reducing activity (MRA) and oxygen consumption (OC), as well as the lipid oxidation, were determined over 7 days of display at 4°C. Results: Hp-LL had the highest pH (6.92), followed by Hp-PM (6.01), Np-PM (5.76), and Np-LL (5.52). Hp-LL had increased (p<0.05) a*, chroma and % oxymyoglobin during display. Hp-LL also had the highest metmyoglobin (MMb) reducing activity and OC among all the samples, thus, the greatest color stability, although very dark throughout storage, with lowest values for lightness (L*) and yellowness (b*). Np-LL also exhibited relatively high color stability, as a result of its lower % MMb and OC and higher MRA than psoas muscle samples. The 0.2 unit difference of the pH between Hp and Np psoas muscle, resulted in the difference of the color intensity, not the color stability. Interestingly, high pH psoas muscle (Hp-PM) did not have better color stability than Np-PM, and in fact had lower color stability than even Np-LL. The similar level of OC and lipid oxidation cannot explain the difference in color stability between Hp-PM and Np-LL. Conclusion: The Hp does not always show better color stability compared with Np beef, which depends on the muscle type. The balance of MRA and OC is important to keep the color in great intensity and stability in the meantime. [ABSTRACT FROM AUTHOR]

The diet of cattle has been shown to alter both subcutaneous fat and muscle fatty acid composition, and these differences cause a change in the Raman spectra of the fat due to the different chemical bonds associated with these biochemical changes. Because biochemical changes only lead to subtle changes in the Raman spectra, statistical methods based upon chemometric modelling are necessary to extract indicative information on the type of feed consumed. This investigation undertook a feasibility study using a limited sample set derived from two producers in one location to ascertain the potential for Raman spectroscopy to accurately discriminate grain‐fed cattle from grass‐fed cattle and investigated the usefulness of principal component analysis (PCA) and partial least squares discriminate analysis (PLS‐DA) to best discriminate between feeding groups using the information from the Raman spectra. The first two principal components accounted for 83% of the variation in the spectra and demonstrated discrimination of samples by feed type. PLS‐DA resulted in a model that was able to accurately predict grain‐ and grass‐fed carcases with a misclassification rate of 3.5%. Changes in beef cattle diets lead to subtle changes in subcutaneous fat; using Raman spectroscopy with chemometric modelling, these changes can be identified and used to identify the production system of beef products. This study successfully uses Raman spectroscopy as an automated, nondestructive and rapid technique in the range of 600–2000 cm−1 in combination with pattern recognition of unsupervised (PCA) and supervised (PLS‐DA) techniques to classify the production system of cattle between grain and grass fed. [ABSTRACT FROM AUTHOR]

Determining the age of the cattle is important in the cattle industry especially for trading purposes. Dentition and ossification scores are currently used to estimate the age of cattle. Both these methods have limitations which can create significant differences in carcass value. In this study, a fibre-optic probe-based spatially resolved diffuse reflectance spectroscopy system was used to investigate the possibility of using visible-near-infrared spectra for predicting the chronological age of beef cattle. This investigation was carried out on hide samples taken from 80 cattle with accurate date of birth and of the same breed. Spectra of hide samples taken from the neck area were used to build partial least squares models to estimate the age of the cattle. Various empirical pre-processing methods and wavelength selection using genetic algorithm (GA) were used to investigate whether these approaches could enhance model performance. Model performance was evaluated using the repeated learning-testing (RLT) method. A model with the lowest average root mean square error of prediction (ARMSEP) of 2.0 years was obtained when reflected intensity spectra collected from a source-detector distance of 1.0 mm was used after pre-processing with automatic Whittaker filter and applying wavelength selection using GA indicating the feasibility of this method for estimating the age of cattle. Two approaches for utilising measurements from all the source-detector distances collected by the spatially resolved measurement system were also considered. Both these approaches, co-adding and data fusion through augmentation, led to poorer model performance compared to using measurements from only one source-to-detector distance. [ABSTRACT FROM AUTHOR]

In this study, the relationship between sensory evaluation and several objective metrics of beef tenderness was tested. Objective metrics included shear force, sarcomere length, collagen content, myofibrillar, and sarcoplasmic protein solubility and particle size analysis. These results were compared to consumer panel scores of tenderness for the same aged beef striploin (longissimus lumborum muscle) samples. There was found to be a significant relationship between sarcomere length, shear force, and particle size with tenderness scores. Collagen content and protein solubilities were not associated to tenderness scores (p > 0.05). Sarcomere length contributions for explaining tenderness variation were overlapped by the contributions of shear force (collinearity). Independent models demonstrated that the lower 95% confidence interval of the fitted regression line exceeded 50% acceptance of tenderness when shear force values <42.6 N and when particle size values <198 μm. We can recommend these as thresholds for consumer acceptance of beef tenderness, although considerations of sample type, analytical methodology, and consumer demographics should be made prior to their adoption. This provision was based on the variation in tenderness scores evident between individual panelists and experimental striploins. [ABSTRACT FROM AUTHOR]

The potential of spatially offset Raman spectroscopy (SORS) for distinguishing different beef cuts was investigated. Six different retail beef cuts (rump, Scotch fillet, round, chuck, tenderloin, and T‐bone) were analysed spectroscopically using SORS. This technique makes it possible to measure the Raman signal 5 mm below the surface of meat muscles, allowing non‐invasive analysis of meat samples that are not readily feasible using conventional Raman spectroscopy. This study has shown for the first time that monitoring of the changes in glycogen, fat, and protein content of muscles can be investigated directly and, most importantly, non‐invasively within various meat cuts. The spectral results reveal differences in structure‐sensitive bands from the amide I and III regions as well as from cysteine, glutamic acid, and phenylalanine vibrations. Statistical analysis confirms these observations based on strong clustering of SORS bands (this was derived from principal component analysis scores of the SORS data) measured for the different cuts. Highlights: Deep Raman spectroscopy was employed to investigate the subsurface composition of meatNon‐invasive differentiation of dissimilar meat cutsIdentification of biomarker bands for each individual meat cutsStatistical analysis clustering of each meat cut confirmed the spectroscopic results [ABSTRACT FROM AUTHOR]

Summary: The global population is becoming older, and still, this cohort considers red meat (beef and sheep meat) as an important staple in their diet. It is understood that the requirements from these red meats will vary as a person ages, often because of associated physiological changes; nutrition and health concerns; and reduced sensorial capacities. This creates an imperative to develop red meat products that appeal and satisfy the demands of elderly people. Here, we have reviewed current literature with the aim to comprehend the elderly consumer market, their demands for nutritive and quality traits, and their requirements for safe and convenient red meat (beef and sheep) products. Based on these studies, it was apparent that these specifications may be delivered using available knowledge of intrinsic and extrinsic influences on red meat if considered within the context of elderly customers, that is, to deliver upon elderly people's requirements for conventional red meat products which are inexpensive, of consistent and perceivable high quality, and quell any associated health concerns for the consumer. [ABSTRACT FROM AUTHOR]

Chilling procedures have been widely used in livestock abattoirs since the development of refrigeration systems. The major criteria when applying chilling regimes is not only complying with regulations, but economic concerns, and also meat safety and quality assurance requirements. Given recent developments, an updated review is required to guide the industry to choose the best chilling method and to inspire the development of new approaches to chilling. Thus in this paper, the quality and microbial safety of beef, lamb, pork, venison, and bison resulting from different chilling treatments has been reviewed, as well as the underlying mechanism(s) for the different impacts on meat quality traits as a result of different chilling regimes. The effect of fast chilling on the tenderness of beef and lamb is a focus, as some new findings, have recently been reported, while multistep chilling is highlighted as it incorporates the advantages of fast chilling to reduce carcass weight loss, resulting in similar quality improvements as found with slow chilling. It is, suggested, that if spray chilling can be combined with the second phase of multi‐step chilling, it will benefit the meat industry in terms of both meat quality and safety. Future studies should focus on combinations of chilling methods with new technologies, such as medium voltage electrical stimulation, muscle stretching, or ultrasound and so on, to move meat quality and safety to a new level. [ABSTRACT FROM AUTHOR]

This study compared the modified Soxhlet (Soxtec) and Folch extraction methods for determining the total lipid or intramuscular fat (IMF) content of aged beef samples. Ageing periods tested were 0, 5, 8, 10 and 12 weeks during which samples were held in vacuo and at ~ 1.0 °C. Prior to solvent extraction, all samples were freeze-dried and ground. The Folch method was found to result in higher IMF values and therefore higher extraction efficiency when compared to the Soxtec. A linear relationship was evident between the two methods that described 80.9% of the variation between IMF values. An interaction between ageing period and extraction method was identified, although ageing period did not independently impact on averaged IMF findings. Based on these observations and reagent toxicity not being a limiting factor, it is recommended that the Folch extraction method be used to determine beef IMF, although it is acknowledged that the Soxtec method IMF results were strongly aligned with those found using the Folch extraction method and tended towards comparability for beef aged < 5 weeks. [ABSTRACT FROM AUTHOR]

Spatially off-set Raman spectroscopy (SORS) offers non-invasive chemical characterisation of the sub-surface of various biological tissues as it permits the assessment of diffusely scattering samples at depths of several orders of magnitude deeper than conventional Raman spectroscopy. Chemicals such as glycogen, glucose, lactate and cortisol are predictors of meat quality, however detection of these chemicals is limited to the surface of meat using conventional Raman spectroscopy as their concentration is higher within the tissue. Here, we have used SORS to detect spectral bands for glycogen, lactate, glucose and cortisol beneath the surface of meat tissue by spiking. To our knowledge, this is the first report on this method for potential application in meat quality analysis. We further validate our SORS spectral results using chemometric analysis to determine chemical-specific spectral characteristics suitable for chemical identification. The chemometric analysis clearly shows distinction of spiked metabolites into four distinct groups, even for such chemically similar compounds as glucose, glycogen and lactate. [ABSTRACT FROM AUTHOR]

BACKGROUND: The aim of this study was to evaluate the effect of dietary lycopene powder on meat quality and the oxidative stability of lipid and protein of longissimus thoracis (LT) in lamb. A total of 30 male lambs were randomly sampled from three feeding groups (control without lycopene supplement, 200 and 400 mg kg−1 lycopene powder respectively) after 3 months of feeding. The muscle samples were taken after slaughter and stored at 4 °C for 7 days. RESULTS: Compared with the control, the results showed that supplementation with lycopene powder gave a higher a* value (redness), and increased the levels of vitamin A and vitamin E. Increasing dietary lycopene powder resulted in a lower degree of lipid and protein oxidation, as evidenced by lower contents of thiobarbituric acid‐reactive substance and carbonyl compounds, and higher levels of sulfhydryl groups. CONCLUSION: Dietary lycopene powder is an effective antioxidant that blocks the oxidation of meat proteins and lipids, and has a positive effect on increasing lamb meat quality during storage. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

This study evaluated a microwave (Mw) cooking method for determining beef toughness using the Warner–Bratzler slice shear force (WBsSF) protocol. Longissimus thoracis muscles were aged for 1, 10, 19, and 28 days at 4C. They were then either cooked on a clam‐shell grill until reaching an internal temperature of 72C, in a Mw for 100 s at maximum power (Mw100) or for 140 s at 60% of maximum power (Mw60). Cooking loss and shear force (SF) values were higher in Mw samples than in grilled ones. SF assessment by grill and Mw100 were able to discriminate tenderness by aging times in the same way as the sensory panel. The SF measured in a grilled sample had higher repeatability (R = .74) and correlation with sensory scores (r = −.79) than Mw100 (R = .61; r = −.62) and Mw60 (R = .51; r = −.53). Mw100 can be considered as an appropriate alternative for the WBsSF protocol. Practical applications: Tenderness is the most important attribute for consumers. Many studies have evaluated tenderness in meat and different protocols for cooking. This work was intended to optimize and evaluate the use of the microwave as a cooking method for shear force determination, against a standard protocol and establish the correlation to sensory tenderness. [ABSTRACT FROM AUTHOR]

Genetic correlations between 16 meat quality and nutritional value traits and live weight at various ages, live ultrasound fat and muscle depth, carcass measures, and carcass dissection traits were estimated for Merino sheep in the Information Nucleus (IN). Genetic correlations between live weight at various ages and the carcass traits are also reported. The IN comprised 8 genetically linked flocks managed across a range of Australian sheep environments. Meat quality traits included between 1,200 and 1,300 records for progeny from over 170 sires for intramuscular fat (IMF), lean meat yield (LMY), shear force (SF5), pH, meat color, and meat nutritional value traits including iron and zinc levels and long-chain omega-3 and omega-6 polyunsaturated fatty acid levels. The genetic correlations indicated that selection of Merino sheep to either reduce fat or increase muscle using ultrasound assessments will result in little change in IMF and SF5. Myoglobin levels would tend to be reduced following selection for reduced ultrasound fat depth (0.35 ± 0.21, 0.43 ± 0.14), whereas increases in myoglobin levels would occur due to selection for increased ultrasound muscle depth (0.25 ± 0.24, 0.38 ± 0.15). Selection for increased live weight will result in favorable correlated responses in hot carcass weight (0.76 to 0.97), dressing percentage (0.13 to 0.47), and carcass muscle (0.37 to 0.95), but unfavorable responses of increases in carcass fatness (0.13 to 0.65) and possible small reductions in muscle oxidative activity (−0.13 ± 0.14 to −0.73 ± 0.33) and iron content (−0.14 ± 0.15 to −0.38 ± 0.16), and a possible deterioration of shear force from selection at later ages (0.15 ± 0.26, 0.27 ± 0.24). Negligible changes are generally expected for LMY and meat color traits following selection for increased live weight (most genetic correlations less than 0.20 in size). Selection for increased LMY would tend to result in unfavorable changes in several aspects of meat quality, including reduced IMF (−0.27 ± 0.18), meat tenderness (0.53 ± 0.26), and meat redness (−0.69 ± 0.40), as well as reduced iron levels (−0.25 ± 0.22). These genetic correlations are a first step in assisting the development of breeding values for new traits to be incorporated into genetic evaluation programs to improve meat production from Merino sheep and other dual-purpose sheep breeds. [ABSTRACT FROM AUTHOR]

Dark cutting in beef and sheep meat has been the subject of extensive research with numerous associations established between it and various production practices. Despite these associations, dark cutting still occurs and causes significant financial losses globally in the fresh meat market. Consumers tend to reject dark meat as it is perceived to be from old or poorly-handled animals and is described as being tough, having an undesirable flavor, and having a short shelf-life. There is no universal system to categorize dark cutting carcasses and meat across countries, although various methods are used to determine the phenomenon. Classifying carcasses as dark cutters on the basis of ultimate pH or color using one muscle, such as the m. longissimus thoracis can lead to mis-description of other muscles within the same carcass and loss of income across the supply chain. The purpose of this review was to identify the factors predisposing animals to dark cutting and to provide recommendations and directions for future research. The review revealed no single production factor causing dark cutting, but that a range of factors or a combination of factors and interactions lead to its occurrence. Dark cutting is a complex condition that can be resolved through comprehensive management of animals, and management of human involvement, and clear guidelines to minimize the incidence of 'dark cutting' meat and to improve the profitability of all sectors in the supply chain are provided here. [ABSTRACT FROM AUTHOR]

This review aims to summarize the relevant published information about the effects of extensive feeding systems on the carcass and meat quality characteristics of lambs. Lambs finished in a feedlot or with supplementation under extensive systems exhibit faster growth rates, achieve target weights quicker, and produce heavier carcass weights when compared to grazing lambs. However, the literature also shows that finishing lambs on high-quality pasture can produce satisfactory growth rates without compromising carcass and meat quality traits. Lately, the consumer demand for products perceived as 'healthy' and that are produced where animal welfare is optimal under systems which do not impact negatively on the environment, has heightened the interest in lamb production under extensive systems. Lambs raised on pasture can meet many of these specifications. Also, lambs fed higher quality green pasture can produce meat with greater amounts of health-claimable omega-3 fatty acids such as eicosapentaenoic acid plus docosahexaenoic acid than feeding systems based on feedlot pellets, grain, or dry pasture/straw. It is apparent that in some previous published research, the number of animals allocated for each treatment, and the lack of replicates, makes it difficult to formulate a correct understanding of the effect of forages on lamb carcass and meat quality. Future research should concentrate on the effect of legume, improved pasture, and specialized forage finishing systems on growth rate, carcass traits, and nutritional value of meat using well-designed experiments with an adequate number of lambs and appropriate paddock replicates per treatment. [ABSTRACT FROM AUTHOR]

A number of studies have shown that dietary omega-6 and omega-3 long-chain fatty acids can be incorporated into muscle tissue of ruminants despite the biohydrogenation of dietary fatty acids in the rumen. The main focus of this review is on eicosapentaenoic (20:5 n-3) and docosahexaenoic (22:6 n-3) fatty acids because health authorities around the world consider the sum of these fatty acids as the basis of classifying a food as a source or good source of omega-3 polyunsaturated fatty acids (PUFAs). A high proportion of polyunsaturated fatty acids are hydrogenated in the rumen, leading to a higher concentration of 18:0, but some escapes the rumen to be absorbed intact by the small intestine. Feeding strategies for ruminants have been successfully applied to increase the absorption of PUFAs in the small intestine and therefore to increase the levels of PUFAs in muscle tissue. Protected fats and algae are strong candidates to improve the nutritional value of red meat in ruminants in terms of health-claimable omega-3 fatty acids. Efforts to understand the genetic basis of fatty acid metabolism have been underway. The knowledge of the main genes which control the output of omega-3 fatty acids is still lacking, but gene expression studies have helped to explain the deposition of these acids in muscle, liver, and subcutaneous fat. [ABSTRACT FROM AUTHOR]

This study investigated the effect of finishing diet, sire type and dam type on major saturated (C12:0, 14:0, 16 : 0 and 18:0) and monounsaturated (oleic; C18:1cis) fatty acid concentrations in meat from lambs grown at eight production locations across Australia. Sires were selected from Merino, maternal and terminal meat breeds; while the dams consisted of ~80% pure Merino and 20% crossbred (Border Leicester x Merino) types. Lambs were generally maintained under extensive pasture conditions, but were fed grain, hay or feedlot pellets when the pasture supply was limited. Lambs were slaughtered over 3 consecutive years (2008-10), with 28-30 slaughter days per year. At 24 h post-mortem, 20-g muscle samples (longissimus lumborum: LL) were taken for fatty acid determination. Lambs from Hamilton, Katanning and Kirby had a higher (P < 0.001) concentration of major saturated (palmitic and stearic) and oleic acids in meat that is proposed to be associated with those lambs being fed diets higher in cereal grain content. Saturated fatty acids, except lauric acid, were lower (P < 0.02) in lambs sired by Merino or terminal type than lambs sired by maternal type. The use of Merino as the sire or dam reduced (P < 0.001) the major saturated fatty acids in LL. Crossbred dam type increased (P < 0.01) the oleic acid concentration in the LL, but sire type had no effect. The results demonstrate that the finishing diet type or sire type or dam type can significantly influence the concentration of major saturated (palmitic, stearic) and/or oleic acids in meat from lambs produced under different production systems in Australia. The medical profession recommends consumers source meat with low levels of saturated fats and lean lamb, trimmed of all salvage fat, can provide this. This is generally applicable to lamb produced across a range of environments despite variation due to diet (grain based diets higher) and breed types. The results show that if consumers eat lean lamb and remove salvage fat, which is now common practice, the meat will have acceptable levels of saturated fat. [ABSTRACT FROM AUTHOR]

Lipid oxidation of M. longissimus lumborum in fresh or vacuum packaged (aged) lamb meat stored at 3 °C for 0 or 4 weeks, respectively and displayed under refrigerated conditions for a further 4 days was assessed by measuring the concentration of malondialdehyde (MDA) in meat using the thiobarbituric acid reactive substances procedure. The effects of vitamin E, heme iron and polyunsaturated fatty acids (n-6 and n-3) on lipid oxidation were examined. Results showed a strong positive relationship between heme iron, n-6 and n-3 fatty acids and lipid oxidation when vitamin E was below 2.95 mg/kg muscle. When lipid oxidation was related to vitamin E concentration and the other three variables, respectively, any increase in heme iron or n-6 or n-3 fatty acids concentration did not influence lipid oxidation. Management of diet to elevate muscle vitamin E concentration above 3.45 mg/kg muscle is beneficial to maintain the level of lipid oxidation below 2.4 mg MDA/kg muscle in meat stored for up to 4 weeks. This demonstrates that vitamin E concentration in muscle has a greater influence on controlling lipid oxidation in muscle tissues than do heme iron or polyunsaturated fatty acids. [ABSTRACT FROM AUTHOR]

Algae high in docosahexaenoic acid (DHA) may provide a source of long-chain omega-3 polyunsaturated fatty acids (LCn-3PUFA) for inclusion in the diet of lambs to improve the LCn-3PUFA status of meat. The effect of background LCn-3PUFA status on the metabolism of high DHA algae is, however, unknown. The aim of the current study was to determine whether the response to a high in DHA algae supplement fed to lambs for six weeks prior to slaughter was mediated by a maternal periconceptional diet. Forty Poll Dorset × Border Leicester × Merino weaner lambs were allocated to receive either a ration based on oat grain, lupin grain, and chopped lucerne (control) or the control ration with DHA-Gold™ algae included at 1.92 % DM (Algae) based on whether the dams of lambs had previously been fed a diet high in n-3 or n-6 around conception. LCn-3PUFA concentration was determined in plasma and red blood cells (RBC) prior to and following feeding. The concentrations of EPA and DHA in the plasma and RBC of lambs receiving the control ration were significantly ( p < 0.001) lower when lambs received the ration for 14 days compared with pre-feeding concentrations. The concentrations of EPA and DHA were also significantly ( p < 0.001) higher when lambs consumed the Algae ration compared with the control ration for 42 days. The increase in EPA and DHA was, however, significantly ( p < 0.05) lower if lamb dams had previously been fed a diet high in n-6 at conception. Assessing the previous nutrition and n-3 status of lambs may allow producers to more accurately predict the likely response to supplements high in LCn-3PUFA, particularly, DHA. [ABSTRACT FROM AUTHOR]

The use of exogenous proteases to improve meat tenderness has attracted much interest recently, with a view to consistent production of tender meat and added value to lower grade meat cuts. This review discusses the sources, characteristics, and use of exogenous proteases in meat tenderization to highlight the specificity of the proteases toward meat proteins and their impact on meat quality. Plant enzymes (such as papain, bromelain, and ficin) have been extensively investigated as meat tenderizers. New plant proteases (actinidin and zingibain) and microbial enzyme preparations have been of recent interest due to controlled meat tenderization and other advantages. Successful use of these enzymes in fresh meat requires their enzymatic kinetics and characteristics to be determined, together with an understanding of the impact of the surrounding environmental conditions of the meat (pH, temperature) on enzyme function. This enables the optimal conditions for tenderizing fresh meat to be established, and the elimination or reduction of any negative impacts on other quality attributes. [Supplementary materials are available for this article. Go to the publisher's online edition of Critical Reviews in Food Science and Nutrition for the following free supplemental files: Additional text, tables, and figures.] [ABSTRACT FROM PUBLISHER]

Oxidation of meat occurs under postmortem conditions and is inevitable. This oxidation includes the biochemical changes in meat leading to changes in color pigments and lipids. As a consequence, color deteriorates, and undesirable flavors and rancidity develop in meat thereby impacting on consumer appeal and satisfaction. Across carcasses, there is variation in the rate at which muscle undergoes chemical reactions under postmortem conditions that reflect inherent variation at the biochemical level. It is expected that this underlying biochemical variation will be reflected in living muscle through oxidative processes. The oxidative process of muscle tissues will vary according to an animal's immunity status, temperament, and ability to cope with stress, with all these affected by nutrition, genetics, management practices, and environmental conditions (hot and cold seasons). Identification of biomarkers that indicate the oxidative status levels of animals or muscle tissues in vivo could provide insight as to how the muscle will respond to the anoxic conditions that produce undesirable results in meat. This review outlines the potential use of 1 group of biomarkers, the isoprostanes, in the context of complex biochemical reactions relating to oxidative processes that take place in the biological systems of live animals ( in vivo) and subsequently in meat ( in vitro). [ABSTRACT FROM AUTHOR]

The hydrolytic activity of 3 commercially available protease preparations (bacterial protease G, fungal 31000, and fungal 60000) were examined using fluorescent-labeled casein, azo dye-impregnated collagen, and meat protein extracts from bovine M. semimembranosus and Achilles tendon, and compared to that of papain. Assays showed that all proteases exhibited little activity at low temperature (5 °C), and maximal activity at 45 °C. The pH, at which optimal activity was observed for each of the protease preparations, differed and ranged from pH 5.0 to 8.0. Kinetic parameters (KM and Vmax) were also different between protease preparations, with the bacterial protease G and papain exhibiting significantly higher Vmax values ( P < 0.001) and lower KM values ( P < 0.01) for the casein substrate than the 2 fungal protease preparations. Meat protein hydrolysis was displayed on SDS-PAGE and proteins analyzed with mass spectrometry. The protease preparations were shown to have varying affinity toward different meat proteins. The bacterial protease G preparation was efficient at hydrolyzing most myofibril and collagen proteins, and appeared to be more efficient than papain at hydrolyzing collagen proteins. On the other hand the 2 fungal protease preparations showed a selective specificity toward meat myofibrillar proteins, and the fungal 60000 protease preparation exhibited high affinity toward collagen γ and collagen type I chain B proteins. The results generated in this study demonstrated that these commercial proteases have good potential for use in meat tenderization applications due to their mild and complementary effects on different meat proteins. Practical Application: Bacterial and fungal protease preparations exhibited varying affinities for hydrolyzing meat proteins. This selective moderate capability of microbial proteases compared to papain is potentially an advantage in avoiding over-tenderization in meat. On the other hand, the bacterial protease G preparation, which appeared to be more efficient at hydrolyzing connective tissue proteins than papain, could be beneficial in tenderizing meat with high connective tissue content. The synergistic effect of these protease preparations could be incorporated into a meat tenderizing formula to give the tenderizer a broad activity spectrum, thus able to target different cuts of meat. [ABSTRACT FROM AUTHOR]

We evaluated the effects of full-fat black soldier fly larvae (BSFL) on broiler carcass composition, cut yield, and breast meat quality. Broilers were fed for 42 days with up to 20% dietary inclusion of BSFL (0, 5, 10, 15, and 20%). On day 42, 120 broilers were slaughtered, and images were taken using computed tomography. Breasts, drumsticks, and thighs were collected for cut yield determination. The pH, color, lipid oxidation, cooking loss, shear force, amino acid profile, and fatty acid profile of the breast meat were assessed. There was no dietary effect on carcass composition or meat quality parameters except for fatty and amino acids compositions. When 20% BSFL was included in the diet, individual fatty and amino acids, such as lauric and myristic acids, aspartic acid, glutamine, and lysine, increased by 22.0-, 5.50-, 1.08-, 1.06-, and 1.06-fold, respectively (p < 0.05). Although total polyunsaturated fatty acids decreased, eicosapentaenoic fatty acids (EPA) increased by 78% in the 20% BSFL inclusion group. In conclusion, up to 20%, dietary full-fat BSFL did not affect key meat characteristics but positively increased the levels of the health-claimable omega-3 fatty acid EPA. [ABSTRACT FROM AUTHOR]

Simple Summary: The increased incidence of heat stress in lambs has been reported in many countries, especially warmer parts of the world, compromising lamb welfare, having flow on effects for meat quality traits. While heat stress impacts can be variable depending on the severity and duration, the exposure of lambs to one week of elevated temperature increased the muscle omega-6 fatty acid concentration compared with the thermoneutral group. The one week heat stress is believed to enhance pro-inflammatory actions through induced free radical formation and oxidative stress. Somewhat independently, supplementation of the diet with vitamin E improved the growth rate and reduced oxidative stress. This suggests that under more extreme heat stress conditions, lambs fed in feedlots would benefit from enhanced levels of antioxidants such as vitamin E. The impact of antioxidant supplementation and short-term heat stress on lamb body weight gain, meat nutritional profile and functionality (storage stability of lipids and colour) of lamb meat was investigated. A total of 48 crossbred ((Merino × Border Leicester) × Dorset) lambs (42 ± 2 kg body weight, 7 mo age) were randomly allocated to three dietary treatments (n = 16) by liveweight (LW) that differed in dosage of vitamin E and selenium (Se) in the diet. Vitamin E and Se levels in the control (CON), moderate (MOD) and supranutritional (SUP) dietary treatments were 28, 130 and 228 mg/kg DM as α-tocopherol acetate and 0.16, 0.66 and 1.16 mg Se as SelPlex™/kg DM, respectively. After four weeks of feeding in individual pens, including one week of adaptation, lambs were exposed to two heat treatments. Animals were moved to metabolism cages for one week and subjected to heat treatments: thermoneutral (TN; 18–21 °C and 40–50% relative humidity) and heat stress (HS; 28–40 °C and 30–40% relative humidity) conditions, respectively. Final LW and hot carcass weight were influenced by dietary treatments with higher final live weight (FLW) (p = 0.05; 46.8 vs. 44.4 and 43.8 kg, respectively) and hot carcass weight (HCW) (p = 0.01; 22.5 vs. 21.3 and 21.0 kg, respectively) recorded in lambs fed the SUP as opposed to the CON and MOD diets. Vitamin E concentration in the longissimus lumborum (LL) muscle tended to be higher in lambs fed MOD or SUP diets than the CON group. Lipid oxidation of aged meat at 72 h of simulated retail display was reduced by antioxidant supplementation. Short-term (one week) heat stress treatment significantly increased muscle linoleic acid and total omega-6 concentrations compared with the CON group. The results demonstrate that four-week antioxidant supplementation at the SUP level improved animal productivity by increasing LW and carcass weight and the functionality of meat exhibited by reduced lipid oxidation. An increase in muscle omega-6 fatty acid concentration from short-term heat stress may induce oxidative stress via proinflammatory action. [ABSTRACT FROM AUTHOR]

Norway has vast rangeland resources (292,361 km2) with an estimated carrying capacity of nearly four million sheep and lambs, twice the current number. However, the intensive production system currently applied has led to more concentrate dependency, resulting in heavier animals in addition to poorer utilization of rangelands and homegrown feed. Intensive feeding systems indirectly influence the sustainability of ecosystems by promoting intensive cropping that can deplete soil fertility and threaten landscape preservation and biodiversity. By contrast, extensive grazing systems can produce environmentally and animal-friendly food products and contribute to regulating soil health, water and nutrient cycling, soil carbon sequestration, and recreational environments. In this paper, the economics of current sheep feeding practices in Norway, using a linear programming model, were compared with more extensive systems which allow for higher usage of on-farm feed resources. Changes in current sheep farming practices have the potential to increase lamb meat production relative to mutton production, in addition to improving the year-round supply of fresh meat. The investigated alternatives, using the Norwegian White Sheep (NWS) breed, suggest that delayed lambing is useful only on farms with abundant pastures available for autumn feeding. Lambs achieve a better market price than hoggets and mature sheep. Therefore, based on the current Norwegian meat market and price offered per kilogram of meat for lamb, an increase in NWS lamb production improves farm profits. On the other hand, when the aim is on greater use of homegrown feed and rangelands, this can be achieved through hogget production, and the quantity of concentrates required can be reduced substantially. [ABSTRACT FROM AUTHOR]

The morphological and productive aspects of Norwegian sheep have developed over time and adapted to the diverse environment of the country. Before 1900, native Norwegian sheep were crossed with UK breeds to attain higher body weight and reproductive efficiency. Subsequent selection programs eventually led to the creation of the heavier (adults often >90 kg) Norwegian White Sheep (NWS), today constituting 70% of the recorded ewes. The modern Norwegian (White) Spæl (NS) sheep, mostly <75 kg and accounting for 10% of the recorded ewe population, originated from the native short-tailed breeds that are smaller and are believed to prefer grazing at higher altitudes than NWS. Other registered breeds of the short-tailed spæl type account for another 12% of the recorded sheep. Rugged Norwegian terrain with rich summer pastures makes the NS a complementary breed to the NWS. Increasing demand for year-round fresh meat requires changes at the farm level. Efficient use of local feed resources by extensive feeding of smaller size ewes is an opportunity for attaining economic gains and for year-round fresh meat production. The NS has a lighter bodyweight, requiring less housing space, is efficient in grazing rangeland and local pastures, and is better suited to outdoor winter grazing in coastal and fjord areas. In this paper, we compare the farm profitability (gross margin) of two Norwegian sheep breeds (NS and NWS) using a linear programming model designed for the coastal and fjord areas. The impact of ewe body weight, housing capacity, and meat produced per unit of concentrate are discussed. [ABSTRACT FROM AUTHOR]

The cover image is based on the Research Article Dietary lycopene powder improves meat oxidative stability in Hu lambs by Chenchen Xu et al., DOI: 10.1002/jsfa.9282. The cover image is based on the Research Article Dietary lycopene powder improves meat oxidative stability in Hu lambs by Chenchen Xu et al., DOI: 10.1002/jsfa.9282. [ABSTRACT FROM AUTHOR]

A review of the literature was conducted on the effects of high temperature and low pH (HTLP) on meat quality, with a focus on interventions that increase the rate of cooling post slaughter. HTLP can potentially change meat tenderness, water-holding capacity and colour due primarily to protein denaturation during the first 5 h post mortem. Deep muscles in large carcasses are susceptible to HTLP when cooled conventionally. Ante mortem and post mortem solutions that increase the rate of carcass cooling are discussed. Ante mortem solutions include access to feed and water, showering with water and provision of shade. Post mortem solutions included vascular flushing, hot fat trimming, opening seams, hot boning, spray chilling, blast chilling, immersion cooling, and very fast chilling. Accelerating rigor with electrical stimulation before HTLP remains controversial. Combinations of different techniques, that suit the specific requirements of a particular processing plant, is the likely best solution to HTLP, but further development of commercial solutions is suggested. High temperature with low pH reduces the quality of deep muscles in large beef carcasses. A review of the literature was conducted with a focus on the cooling rate of beef carcasses in the first 5 hours post slaughter. This can be achieved by reducing body temperature in both the ante and post mortem periods using a range of methods. [ABSTRACT FROM AUTHOR]