Search

Chilled beef is inevitably contaminated with microorganisms, starting from the very beginning of the slaughter line. A lot of studies have aimed to improve meat safety and extend the shelf life of chilled beef, of which some have focused on improving the decontamination effects using traditional decontamination interventions, and others have investigated newer technologies and methods, that offer greater energy efficiency, lower environmental impacts, and better assurances for the decontamination of beef carcasses and cuts. To inform industry, there is an urgent need to review these interventions, analyze the merits and demerits of each technology, and provide insight into 'best practice' to preserve microbial safety and beef quality. In this review, the strategies and procedures used to inhibit the growth of microorganisms on beef, from slaughter to storage, have been critiqued. Critical aspects, where there is a lack of data, have been highlighted to help guide future research. It is also acknowledge that different intervention programs for microbiological safety have different applications, dependent on the initial microbial load, the type of infrastructures, and different stages of beef processing.

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.

Background Meat is a perishable product and during storage, the actions of microorganisms and endogenous enzymes result in chemical compositional changes. Total volatile basic nitrogen (TVB-N) is often used as a biomarker of protein and amine degradation. The broad adoption of TVB-N to interpret meat freshness is somewhat restricted. This is the result of limited or inconsistent knowledge pertaining to the association between TVB-N and other freshness parameters, for beef, sheep/goat meat, pork, chicken and other types of meat, especially when compared to fish. Current meat studies have failed to address the mechanisms between TVB-N generation and production, processing and preservation strategies. Scope and approach Etiology of spoilage and freshness indicators in fresh meat are discussed and various mechanisms contributing to meat spoilage are highlighted. Further, the use and application of TVB-N for understanding the freshness of different meat types has been comprehensively reviewed with the aim of establishing its usefulness as a freshness marker. Key Findings and Conclusions TVB-N increases with meat storage and is aligned with other biomarkers of spoilage (i.e. function of duration, temperature, packaging, etc.). But these increases are not always consistent. There are different recommendations of TVB-N limits for meat freshness. These are primarily for fish and seafood products and therefore inappropriate for other meat types, are species specific, arbitrary, or have an element of ambiguity (e.g. an intermediary ‘stale’ classification between fresh and spoilt states). The selection of TVB-N limits can therefore introduce inaccuracy and subjectivity into the appraisal of meat freshness. Several destructive and non-destructive methods have been used to determine TVB-N, however, their capacity is limited to the differential between spoilt and non-spoilt samples through chemometric classification systems based on predefined TVB-N guidelines. Further reference populations and investigations of red meat types are required.

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.

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

This study evaluated the effects of different doses (0, 4, 8, 12, 16 kGy) of low-energy electron beam (LEEB; 0.2 MeV) on the quality changes of vacuum-packaged beef steaks during chilled storage for 21 days. LEEB irradiation at a low dose (4 and 8 kGy) significantly elevated the L* values of steaks, and did not deteriorate the a* values, the oxidation of lipid and protein (P 0.05) compared to non-irradiated samples. LEEB irradiation (4 and 8 kGy) also significantly reduced the bacterial loads compared with non-irradiated steak, which may be due to the inactivation effect on Acinetobacter, Brochothrix thermosphacta, Carnobacterium divergens, Leuconostoc and Serratia during storage. Albeit all doses retained more acceptable sensory characteristics compared to non-irradiated samples, LEEB irradiation with8 kGy significantly reduced the L* values and promoted protein oxidation. Overall, the LEEB irradiation with 4-8 kGy could be used as a promising innovative technology for extending the shelf-life of vacuum-packaged chilled beef steaks.

With the aim to define an objective threshold for consumer satisfaction, this study investigated the relationship between lamb particle size data and consumer scores for tenderness, juiciness, flavour and overall liking (sensorial properties). Data were sourced from the longissimus lumborum muscles of 273 Australian Merino lambs, these being aged for 5-d and then analysed for particle size and sensorial properties - the latter using untrained consumer sensory panels. Pearson's correlation and principal component analyses identified no significant relationship between particle size and consumer sensory scores. Linear regression models found the sensorial properties of lamb could not be predicted using particle size, indicating no univariate relationship. Further, a backwards stepwise regression analysis found there to be no multivariate or univariate relationship between the sensorial properties of lamb and its particle size. These findings demonstrate that there is little value in defining a particle size threshold for consumer satisfaction based on the sensorial properties of lamb.

The quality, colour, and shelf-life of wet aged grass and grain-fed beef were compared. Striploins (n = 24) were each divided into 6 portions and were assigned to different ageing periods (0, 3, 5, 8, 11, or 14 weeks). Analysis demonstrated that declines in shear force and particle size occurred within the first 3 weeks of ageing. Extended ageing resulted in increases in beef purge and pH; and decreases in total moisture, drip, and cooking loss. The initial grass-fed beef drip (3.1%) and particle sizes (201.0 μm) were higher than for grain-fed beef (1.8% and 145.2 μm, respectively). Total viable counts were 7 cfu/g after 5 weeks of ageing. Total volatile basic nitrogen was15 mg/100 g, even after 14 weeks of ageing. Product line by ageing period interactions affected vitamin E and colour parameters. In conclusion, wet aged beef maintains 'acceptable' microbial loads for 5-8 weeks, irrespective of product line and without any deterioration in its quality.

Meat quality data can only be obtained after slaughter when selection decisions about the live animal are already too late. Carcass estimated breeding values present major precision problems due to low accuracy, and by the time an informed decision on the genetic merit for meat quality is made, the animal is already dead. We report for the first time, a targeted next-generation sequencing (NGS) of single nucleotide polymorphisms (SNP) of lipid metabolism genes in Tattykeel Australian White (TAW) sheep of the MARGRA lamb brand, utilizing an innovative and minimally invasive muscle biopsy sampling technique for directly quantifying the genetic worth of live lambs for health-beneficial omega-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFA), intramuscular fat (IMF), and fat melting point (FMP). NGS of stearoyl-CoA desaturase (SCD), fatty acid binding protein-4 (FABP4), and fatty acid synthase (FASN) genes identified functional SNP with unique DNA marker signatures for TAW genetics. The SCD g.23881050T&gt, C locus was significantly associated with IMF, C22:6n-3, and C22:5n-3, FASN g.12323864A&gt, G locus with FMP, C18:3n-3, C18:1n-9, C18:0, C16:0, MUFA, and FABP4 g.62829478A&gt, T locus with IMF. These add new knowledge, precision, and reliability in directly making early and informed decisions on live sheep selection and breeding for health-beneficial n-3 LC-PUFA, FMP, IMF and superior meat-eating quality at the farmgate level. The findings provide evidence that significant associations exist between SNP of lipid metabolism genes and n-3 LC-PUFA, IMF, and FMP, thus underpinning potential marker-assisted selection for meat-eating quality traits in TAW lambs.

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.

Individually-housed lambs were used to compare the effect of a grain-based diet supplemented with moderate (MOD) or supranutritional (SUP) levels of vitamin E and selenium, and a lucerne hay-based diet (LUC) on plasma-oxidative stress biomarkers, muscle pH decline and meat quality. Lambs fed LUC had different reactive oxygen metabolite concentrations and biological antioxidant potentials to the MOD and SUP treatment groups. All plasma oxidative stress markers decreased in concentration across the four sampling time points measured over the eight week feeding study, except biological antioxidant potential (BAP). Diet did not impact on lamb muscle pH decline traits. Of the meat quality traits measured, the effect of diet was only significant for shear force which was highest for the LUC lambs. Particle size and carbonyl content in meat were influenced by ageing period. Meat cooking loss, peroxidase activity and oxidation-reduction potentials were not influenced by any experimental factors. These findings show that LUC offers a strategic feeding system that is comparable to MOD and SUP diets.

This study investigated the effects of frozen storage time on the quality and muscle structure in normal and pale, soft and exudative (PSE)-like pork. The meat quality of M. longissimus et lumborum (LL) was studied at 0, 3, 6, 9, 12, 15 and 18 weeks of storage at −18 °C, and M. Biceps femoris (BF) was studied at 0, 3 and 18 weeks of storage at −18 °C. Storage time affected all the measured parameters (pH, thaw loss, TVB-N, shear force and muscle structure). There were no differences between normal and PSE-like meat for thaw loss (%) or TVB-N (mg/100 g) values at all storage times. An initial tenderizing effect in PSE-like samples was observed at weeks 3 and 6 in LL samples, but thereafter samples became tougher during frozen storage and after 3 weeks in the BF. Storage for 6 weeks for PSE-like and 9 weeks for normal pork at −18 °C does not reduce quality.

The bolar blade, striploin and topside cuts from dark cutting (DC) and normal (nDC) beef carcasses were compared in terms of their eating quality, oxidation and colour traits. Carcass grades were assigned so that striploins assessed to have pH > 5.7 were classified DC. Cuts were aged (14 and 28 d) before their shear force, sarcomere length, ultimate pH, particle size, TBARS, drip and cooking losses, and colour stability traits were analysed. DC effects on tenderness traits were not uniform across all cuts. Only TBARS was influenced by grade and ageing period interactions. Colorimetric variation due to grade was more evident in the striploin than the other cuts, although this was independent to ageing or display. Cuts themselves differed and were impacted by ageing and display periods. It was concluded that unlike the topside and striploin, the bolar blade from DC carcasses had comparable quality to nDC and could therefore retain its value if priced independent to the entire carcasses.

Within 24 h post-mortem, loin surfaces of Australian beef carcasses (n = 436) were evaluated using the Nix Pro Color Sensor™ (NIX). The potential for colorimetrics (L*, a*, b*, hue and chroma) to discriminate between dark cutting (DC) and non-dark cutting (nDC) carcasses was compared. For this purpose, a chroma threshold of 30.5 delivered maximum total sensitivity and specificity. The bolar blade, striploin and topside from a selection of DC and nDC carcasses were also removed, aged for 14 d and tested for shear force, drip loss, cooking loss, ultimate pH, colour change over 3 d display (ΔE), and sarcomere length. Association between chroma values and these quality traits were investigated by linear models. The hypothesis of zero slope was rejected (P 0.05) for pH on striploin and topside, but the models had poor predictive ability (R

Pasture contains a lot of terpenes, able to pass throughout oral assumption and inhalation into meat. The aim of this paper was to verify if limonene accumulates in meat after oral or respiratory exposure and to assess its effects on animal oxidative status and meat quality. Thirty-six goat kids were involved and assigned for 1 week to three treatment groups: control group (CG); an oral group (OG), where limonene was administered directly into the mouth (drenched); and a respiratory group (RG), in which limonene was administered via inhalation. The meat limonene concentration for the OG was the highest (P 0.01), although RG showed the highest rate of transfer (P 0.001). Limonene gives the possibility to delay lipid oxidative processes, reducing discoloration and rancidity in meat. However, the respiration route seems to be able to guarantee a greater limonene transfer into meat compared to the oral one.

The maximisation of available resources for animal production, food security and maintenance of human–animal wellbeing is important for an economically viable, resilient and sustainable future. Pasture and forage diets are common sources of short chain omega-3 (n-3) polyunsaturated fatty acids (PUFA), while grain-based and feedlot diets are common sources of short chain omega-6 (n-6) PUFA. Animals deposit n-3 and n-6 PUFA as a result of their direct consumption, as feeds or by synthesis of longer chain PUFA from short chain FA precursors in the body via desaturation and elongation processes. Research conducted over the last three decades has determined that the consumption of n-3 PUFA can improve the health and wellbeing of humans through its biological, biochemical, pathological and pharmacological effects. n-6 PUFA also play an important role in human health, but when consumed at high levels, are potentially harmful. Research shows that current consumption of n-6 PUFA by the human population is high due to their meal choices and the supplied food types. If consumption of n-3 PUFA from land- and marine-based foods improves human health, it is likely that these same food types can improve the health and wellbeing of livestock (farm animals) by likewise enhancing the levels of the n-3 PUFA in their circulatory and tissue systems. Modern agricultural systems and advanced technologies have fostered large scale animal and crop production systems. These allow for the utilisation of plant concentrate-based diets to increase the rate of animal growth, often based on economics, and these diets are believed to contribute to unfavourable FA intakes. Knowledge of the risks associated with consuming foods that have greater concentration of n-6 PUFA may lead to health-conscious consumers avoiding or minimising their intake of animal- and plant-based foods. For this reason, there is scope to produce food from plant and animal origins that contain lesser amounts of n-6 PUFA and greater amounts of n-3 PUFA, the outcome of which could improve both animal and human health, wellbeing and resilience to disease.

Meat scientists often use objective, laboratory-based methods to understand the sensorial properties of red meat. These approaches are advantageous because of their reproducibility, low cost, rapid generation of data and technical ease – comparative to large scale consumer sensory panels. To enhance the value of these methods, effort has been applied to identify specific limits or thresholds that correspond to a consumer's acceptance or satisfaction with the quality of a meat product. From the literature, we observe there to be inconsistencies in these thresholds. This could stem from disparate laboratory methods, consumer panel procedures and demographics, the approach to statistical analysis, sample type and representativeness, and more. This paper aimed to review consumer thresholds, proposed in the literature, to provide insight into their validity and transferability to other studies. Investigations were limited to red meat (beef and sheep meat) and to non-spectroscopic methods that have been used to predict consumer acceptance of colour, tenderness, juiciness, flavour and overall liking.

Ninety-six male goslings were allocated and assigned to treatment using a completely randomized design. Dietary treatments included a basal diet consisting of corn, wheat, and soybean meal with either no additional selenium (CON), 0.3 mg/kg of inorganic selenium (I-Se, sodium selenite), or 0.3 mg/kg of organic selenium (O-Se, selenium-enriched yeast). After a 56-day feeding period, geese were slaughtered on a common ending day and two geese per pen (n = 24) were used for the analyses conducted in this study. Meat (equal portions of the breast and thigh meat) and liver were collected and evaluated for proximate composition, fatty acid profile, pH, phenolic content, thiobarbituric acid reactive substances (TBARS), and total volatile basic nitrogen (TVB-N) over a 9-day storage period at 4 &deg, C. The meat and liver samples from geese supplemented I-Se or O-Se had greater (p &lt, 0.01) lipid content compared with geese not supplemented with additional selenium. At the conclusion of the 9-day storage period, meat and liver samples from geese supplemented I-Se or O-Se had lower (p &lt, 0.05) pH values, greater (p &lt, 0.05) phenolic content, lower (p &lt, 0.05) TBARS values, and lower (p &lt, 0.05) TVB-N compared with geese not supplemented with additional selenium (CON).

Context Finishing lambs on pasture and specialist forages is a commonly used production system in southern Australia; however, there is little information properly comparing multiple pasture options for lamb production. Aim We aimed to compare growth rates of lambs when grazing traditional pastures, novel legumes, or a herb–legume mixture. Methods Six pasture and forage treatments were sown in three replicate 0.4-ha plots and with access to irrigation. Treatments were French serradella (Ornithopus sativus Brot.), bladder clover (Trifolium spumosum L.), forage brassica (Brassica napus L.), lucerne (Medicago sativa L.), lucerne + phalaris (Phalaris aquatica L.), and arrowleaf clover (Trifolium vesiculosum Savi) + chicory (Cichorium intybus L.). The last two treatments were sown in a 1 : 1 alternate sowing-row (tyne) arrangement. All plots were grazed concurrently from 15 October to 2 December 2014, each plot with a mixed-sex group of 13 weaned lambs: five White Dorper, three White Suffolk × White Dorper and five White Suffolk × Merino lambs. During the grazing period, lambs were weighed each week following an overnight curfew. Starting liveweight (mean ± s.d.) was 32.4 ± 5.5 kg. At the completion of the grazing period, lambs were slaughtered and carcass traits recorded. Key results Lambs grazing arrowleaf clover + chicory had the highest average daily growth rates (ADG) (245 g/lamb.day) and those grazing lucerne + phalaris the lowest (119 g/lamb.day). There was a lag in ADG for the forage brassica treatment over the first 14 days of grazing, and lamb growth plateaued for the bladder clover treatment toward the end of the trial. Overall, ADG for the forage brassica and bladder clover treatments was similar to that for lucerne. Lambs grazing French serradella had similar ADG to 18 November compared with those grazing other treatments, except arrowleaf clover + chicory; however, lambs grazing French serradella were withdrawn from the experiment on 26 November after losing weight. The genotype × treatment interaction was significant for final liveweights, with White Suffolk × White Dorper lambs having higher predicted final liveweight on the arrowleaf clover + chicory pasture (45.2 kg) than White Dorper (43.8 kg) and White Suffolk × Merino (44.0 kg) lambs, and higher liveweight on lucerne than White Suffolk × Merino lambs (42.6 vs 41.4 kg). White Dorper lambs had a higher overall sale value owing to their higher dressing percentage. The proportion of lambs reaching the finished weight target was higher for arrowleaf clover + chicory (0.96) than for any other treatment. Conclusions and implications Using a forage option that maintains high levels of production and quality later in spring can increase the proportion of lambs reaching target weights and the final sale weight of lambs.

This study compared longissimus lumborum (LL) and semitendinosus (ST) muscles, in 48 lamb carcasses, to determine their pH decline parameters and achievement of ideal pH criteria (hitting the window). These include the pH at temperature 18 °C (pH@18) and temperature at pH 6 (temp@pH6). No practical difference were found between muscles for pH@18 or the temp@pH6, although there were differences between the experimental carcasses evaluated. Indeed, for all but three carcasses, there were insignificant differences between the LL and ST in terms of their pH@18. This outcome suggests that the lower value and more accessible ST muscle can be measured to determine lamb carcass pH decline parameters, instead of the LL. Because of the scale of this study, additional investigation is advised prior to any adoption.

This study compared the effect of a novel perennial wheat forage and a conventional annual wheat forage, fed to lambs with or without lucerne, on the quality and mineral profile of the longissimus lumborum and semimembranosus muscles. This involved 48 Poll Dorset × Merino ewe lambs, 12 per treatment, managed for 28 days within individual pens. Consumer sensory panel scores showed ‘good eating quality’ for all samples irrespective of diet, a conclusion supported by the shear force, cooking loss, particle size, and intramuscular fat results. Drip loss was affected by a significant interaction between diet and muscle. The ultimate pH of meat from lambs fed annual wheat was highest. Comparable colour stability and purge results suggested that diet did not impact on lamb retail-potential. Sodium, sulphur and zinc concentrations were higher in the meat from lambs fed annual wheat, compared to perennial wheat. Overall, these outcomes support the use of perennial wheat as a forage for lamb production.

This study investigated the effect of feeding unsaleable carrots to lambs within a total-mixed ration (TMR) on performance, carcass characteristics, meat quality and sensory parameters. Thirty-six Australian Merino wether lambs were fed a control (barley-based) or carrot-based TMR for 11-weeks. Carrot-fed lambs had 2.7% higher cold dressing percentage (P = 0.03) while consuming less than control lambs. Subcutaneous fat of carrot-fed lambs contained less branch-chained, and more cis- and trans-monounsaturated fatty acids (FA; P ≤ 0.01) compared to control-fed lambs, which tended (P = 0.08) to have higher concentrations of polyunsaturated FA, despite the Longissimus lumborum (LL) muscle being unchanged by diet. Under retail display conditions, L* and hue values were lower (P ≤ 0.04) for 5 d aged LL samples from carrot-fed lambs. No differences were observed in other meat quality and sensory parameters between diets. Therefore, feeding unsaleable carrots at 45% DM in a TMR can improve lamb performance and carcass characteristics, while maintaining meat quality and FA composition.

This study defined the pH threshold for dark cutting beef of Asian consumers using a web-based survey and examined their preferences for beef appearance. Ninety individual images of beef steaks with different pH values were randomly selected to be scored by 4322 respondents. Gender, age and beef eating habits of respondents were found to impact on color preferences. With respondent's visual score of 4 set as the acceptance threshold, linear regression analysis between visual scores and beef instrumental colorimetrics, showed that the acceptance thresholds of instrumental color values were L* ≥ 31.4, a* ≥ 16.4, b* ≥ 6.5, chroma ≥17.4 and hue ≥22.5. These corresponded to pH threshold values of 6.11, 6.20, 6.28, 6.25 and 6.29, respectively. This pH benchmark (6.11 to 6.29) for dark cutters is higher than pH thresholds applied in most countries, indicating that Asian consumers prefer darker meat than expected, however, the likely tenderness of beef with pH's at this level merits consideration.

Meat eating quality with a healthy composition hinges on intramuscular fat (IMF), fat melting point (FMP), tenderness, juiciness, flavour and omega-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFA) content. These health-beneficial n-3 LC-PUFA play significant roles in optimal cardiovascular, retinal, maternal and childhood brain functions, and include alpha linolenic (ALA), eicosapentaenoic (EPA), docosahexaenoic (DHA) and docosapentaenoic (DPA) acids. The primary objective of this review was to access, retrieve, synthesise and critically appraise the published literature on the synthesis, metabolism and genetics of n-3 LC-PUFA and meat eating quality. Studies on IMF content, FMP and fatty acid composition were reviewed to identify knowledge gaps that can inform future research with Tattykeel Australian White (TAW) lambs. The TAW is a new sheep breed exclusive to MARGRA brand of lamb with an outstanding low fat melting point (28–39°C), high n-3 LC-PUFA EPA+DHA content (33–69mg/100g), marbling (3.4–8.2%), tenderness (20.0–38.5N) and overall consumer liking (7.9–8.5). However, correlations between n-3 LC-PUFA profile, stearoyl-CoA desaturase (SCD), fatty acid binding protein 4 (FABP4), fatty acid synthase (FASN), other lipogenic genes and meat quality traits present major knowledge gaps. The review also identified research opportunities in nutrition–genetics interactions aimed at a greater understanding of the genetics of n-3 LC-PUFA, feedlot finishing performance, carcass traits and eating quality in the TAW sheep. It was concluded that studies on IMF, FMP and n-3 LC-PUFA profiles in parental and progeny generations of TAW sheep will be foundational for the genetic selection of healthy lamb eating qualities and provide useful insights into their correlations with SCD, FASN and FABP4 genes.

Many advances have occurred in the field of smart meat packaging, and the potential for these to be used as tools that respond to challenges faced by industry is exciting. Here, we review packaging solutions to several immediate concerns, encompassing dark cutting, purge and yield losses, product traceability and provenance, packaging durability, microbial spoilage and safety, colour stability, environmental impacts, and the preservation of eating quality. Different active and intelligent packaging approaches to each of these were identified and are discussed in terms of their usefulness - to processors, retailers and/or consumers. From this, it became apparent that prior to selecting a packaging solution, industry should first define their criteria for success (e.g. How much purge is too much? What is a reasonable shelf-life to facilitate product turnover? Is the customer willing to pay for this?), and understand that packaging is not the sole solution, but acts as part of a holistic response to these issues.

Background Meat packaging once acted primarily as an inert barrier to protect its contents against contamination and this function has shifted. Discussion Packaging now includes complementary functions that improve product quality, longevity and customer/retail appeal. The devices and methods applied to achieve these functions may be categorised as smart packaging, which includes intelligent packaging, devised to monitor and communicate packaged content status, and active packaging, to provide passive adjustment of inpack conditions from its interactions with the packaged meat. Conclusion Smart packaging examples already available from recent patents include antimicrobial and antioxidant packaging coatings and inserts; sensors or indicators that identify spoilage and freshness; functional engineering customisations; improvements to packaging integrity; leak or tamper detectors; and, environmentally sustainable options. Together, these inventions respond to industry and customer demands for meat packaging and are therefore the focus of this review, in which we discuss their applications and limitations in meat packaging.

Lipid oxidation and fatty acid (FA) profiles were evaluated for beef M. longissimus lumborum (LL) stored under different chilled-then-frozen storage combinations (up to 5 and 52weeks, respectively) and two frozen holding temperatures (-12°C and -18°C). FA profile variation was observed, with increasing frozen storage periods resulting in unsaturated FA levels declining as saturated FA levels increased. Polyunsaturated and health claimable FA levels also tended to decline with increasing chilled storage period, albeit insignificant within the constraints of the experimental design. Peroxidase activity, TBARS and oxidation-reduction potential analyses reflected these FA changes. These, when compared against existing consumer thresholds, suggest a perceptible detraction from LL held under long-term frozen storage durations that are less evident earlier as dependent on the preceding chilled storage period. Negligible impact of frozen storage holding temperatures was observed on measured traits. These results suggest long-term chilled-then-frozen storage can influence beef lipid stability, healthy FA profile and therefore the healthiness of beef.

This study investigated the effects of chilled and frozen storage conditions on the fatty acid profile and lipid oxidation in lamb M. longissimus lumborum (LL). Muscle LL (n = 360) were randomly selected at 24 h post-mortem from a commercial Australian abattoir and maintained chilled for five periods (0, 2, 4, 6 and 8 weeks) followed by frozen for six periods (0, 4, 8, 12, 24 and 52 weeks) at − 12 °C or − 18 °C. Samples were analysed for fatty acid profile and lipid oxidative parameters (TBARS, oxidation-reduction potential and peroxidase activity). Health-claimable polyunsaturated fatty acids (EPA and DHA) were unaffected by neither storage period nor temperature. TBARS levels did not exceed rancidity thresholds recommended in the literature, with these and other lipid peroxidation parameters showing broad increases in concentration with more ‘long-term’ chilled and frozen storage periods. Combined, the results suggest nutritional and eating quality were maintained across the various chilled and frozen storage conditions applied in this study.

The Nix Pro Colour Sensor™ (NIX) can be potentially used to measure meat colour, but procedural guidelines that assure measurement reproducibility and repeatability (precision) must first be established. Technical replicate number (r) will minimise response variation, measureable as standard error of predicted mean (SEM), and contribute to improved precision. Consequently, we aimed to explore the effects of r on NIX precision when measuring aged beef colour (colorimetrics; L*, a*, b*, hue and chroma values). Each colorimetric SEM declined with increasing r to indicate improved precision and followed a diminishing rate of improvement that allowed us to recommend r=7 for meat colour studies using the NIX. This definition was based on practical limitations and a* variability, as additional r would be required if other colorimetrics or advanced levels of precision are necessary. Beef ageing and display period, holding temperature, loin and sampled portion were also found to contribute to colorimetric variation, but were incorporated within our definition of r.

The effects of dietary supplementation with Azolla pinnata (a macro algae) on lamb performance, blood parameters, carcass traits and meat quality were investigated. Thirty fat-tail uncastrated male Moghani lambs with an initial average body weight (BW) of 28 ± 1.4 kg were allocated to one of three dietary treatments (10 lambs/treatment) by stratified randomisation based on BW. Lambs were fed ad libitum for 90 d with a standard finishing diet containing sun-dried Azolla at 0, 10 and 20 % (DM basis) levels. Results showed that the feed intake tended to be lower (P = 0.074) in Azolla supplemented lambs, the values were 1.73 and 1.69 and 1.48 kg DM/d, for 0, 10 and 20 % Azolla, respectively. Plasma urea and creatinine concentrations were lower in Azolla supplemented lambs than control group (P 0.05) but inclusion of Azolla in the feedlot ration improved (P = 0.004) feed conversion ratio. Hot and cold carcass weights were greater (P = 0.009) for lambs fed with 10 % Azolla (24.9 and 24.4 kg), than for the control group (22.5 and 22.1 kg, respectively). Other carcass traits and longissimus muscle chemical composition were not impacted by Azolla supplementation (P > 0.05). Lambs that were supplemented with 20 % Azolla in the feedlot ration had greater odor intensity scores (P = 0.01) compared with the control group. The sensory properties of meat were not altered by 10 % Azolla diet. Azolla supplementation at 10 % and 20 % had no effect on meat quality attributes (P > 0.05). From these results, the supplementation of Azolla pinnata at 10 % level is recommended as a feed source to improve feed conversion ratio and carcass weights for Moghani lambs, without compromising meat quality and sensory properties.

Beef longissimus lumborum muscles (24) were each portioned into 6 steaks, and these were held at ~0.5 °C for up to 14 weeks. Total volatile basic nitrogen (TVB-N) data was compared against other measures of quality and freshness: total viable microbial count (TVC), ultimate pH, drip loss, purge, moisture content, cook loss, shear force, particle size, vitamin E, intramuscular fat content (IMF) and colour parameters. There was an association between TVB-N and colour parameters; and between TVB-N and several parameters for microbial load, tenderness and moisture. IMF and vitamin E were not correlated to TVB-N. TVB-N of 5.1 mg/100 g (95% confidence intervals: 4.6–5.5 mg/100 g) was estimated as equivalent to a TVC of log 7 cfu/g. When beef samples were categorised as either spoilt or fresh using this TVC recommendation, TVB-N was correct in 77.9% of its assignments. Additional investigation is necessary to confirm this result against a larger sample population with a broader range of TVB-N values.

Beef loins (LL) stored under different chilled-then-frozen storage combinations (up to 5 and 52 weeks, respectively) and two frozen holding temperatures were evaluated for microbial load and meat quality parameters. We found holding temperature effects to be negligible, which suggest − 12 °C could deliver comparable quality LL to − 18 °C across these same storage periods. Meat quality parameters varied significantly, but when compared to existing consumer thresholds these may not be perceptible, colour being the exception which proved unacceptable, earlier into retail display when either chilled and subsequent frozen storage periods were increased. There was insufficient detection of key spoilage microbes to allow for statistical analysis, potentially due to the hygienic and commercially representative LL source, although variation in water activity, glycogen content, pH and other moisture parameters conducive to microbial proliferation were influenced by chilled-then-frozen storage. These outcomes could be applied to defining storage thresholds that assure beef quality within export networks, leveraging market access, and improving product management.

Shear force (SF) is a routine measure used in meat research to define tenderness, but the procedures are not standard. As a result, many studies have failed to include SF block weight and status (frozen or thawed) prior to cooking in their methods sections—potentially due to the unknown extent to which they contribute to SF and cooking loss (CL) variation. Consequently, we investigated the effects of SF block status (frozen or thawed) and weight prior to cooking (pre-cook wt) on SF and CL determination of beef. A split-plot experimental design was applied to 80 SF blocks removed from several beef Musculus longissimus lumborum to represent a range of weights (33.8–120.5 g) balanced by status. These were then cooked using a water bath, and assessed for SF and CL. It was found that pre-cook wt acted as a source of variation for SF and CL measurement (P

This paper reviews current literature relating to the effects of chilled and frozen storage on the quality characteristics of red meat (lamb and beef). These characteristics include tenderness (shear force), juiciness (fluid losses), flavour (lipid oxidation), colour and microbial loading. Research suggests that chilled storage of red meat can improve certain properties, such as shear force and species-specific flavour, to threshold levels before the effects on flavour and colour become deleterious, and key microbial species proliferate to spoilage levels. For frozen red meat, the negative effects upon quality traits are prevented when stored for shorter durations, although chilled storage conditions prior to freezing and retail display post-thawing can both positively and negatively affect these traits. Here, we review the effects of different chilled, frozen and combined chilled and frozen storage practices (particularly the chilled-then-frozen combination) on meat quality and spoilage traits, in order to contribute to superior management of these traits during product distribution.

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

The effect of muscle fibre orientation and measurement interval on lamb meat drip losses was tested using the EZ-DripLoss (EZ) method. Sample cores were removed from 100 semimembranosus (SM) and longissimus lumborum (LL) muscles, sourced from different Merino lamb carcasses. Two cores with either horizontal or vertical fibre orientation, relative to the core diameter, were removed from each SM. One core with vertical fibre orientation was removed from each LL. The drip loss (%) of these cores was then monitored across four 24 h measurement intervals. It was found that fibre orientation did not impact on SM drip losses. Both SM and LL drip losses increased, linear to measurement interval. SM drip loss increased more than LL over the four measurement intervals and consequently, SM drip losses were higher than LL. Longer measurement intervals which are defined in the methods section are recommended when testing lamb meat drip losses using the EZ method.

We investigated the fatty acid (FA) composition, oxidative biomarkers and quality traits of chilled beef. Specifically, striploin portions were held in vacuo and chilled (~ 1.5 °C) for up to 12 weeks, and analysed dependent on their assigned chilled storage period (0, 2, 5, 8, 10 and 12 weeks). There were no practical effects observed on beef FA composition as a result of chilled storage – including several polyunsaturated FA (PUFA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Intramuscular fat content was found to have a covariate effect, but only for saturated FA and monounsaturated FA. Vitamin E and thiobarbituric acid reactive substances were unchanged. Furthermore, improvements to shear force and particle size were evident at 2 weeks and thereafter, no further variation was evident. These findings suggest that beef produced to be healthier based on the EPA, DHA and PUFA content will remain so, for up to 12 weeks. Likewise, beef quality will be preserved across this same period.

The objective was to evaluate the effect of packaging conditions on bacteriological and biochemical changes in beef steaks classified here, as normal ultimate pH (pHu; 5.40–5.79), intermediate pHu (5.80–6.09) or high pHu (≥ 6.10). Steaks were packaged in vacuum packaging (VP) and modified atmosphere packaging with high oxygen (HiO2-MAP) or carbon monoxide (CO-MAP). Headspace, bacterial counts, total volatile basic nitrogen, pH, purge loss, surface color, lipid oxidation, and sensory attributes were monitored over a 14-day storage period at 2 °C. HiO2-MAP and CO-MAP of high pHu steaks resulted in a bright red color even when observed to be spoilt. Reduced purge loss and lipid oxidation, as well as increased sensory acceptability were observed for steaks with elevated pHu. Higher pHu was also accompanied by an acceleration of microbial proliferation. Of all packaging types investigated, CO-MAP exerted the best preservation, regardless of pHu and based on its antibacterial and antioxidant properties.

A small angle X-ray scattering (SAXS) synchrotron was used to evaluate 100 ovine m. longissimus lumborum, representing lamb (n=50) and sheep (n=50). The diffraction of X-rays gives information on muscle myofibril structure and fat content. The linear relationships between SAXS measures with measures such as, shear force, intramuscular fat content (IMF) and collagen content/solubility, were investigated. A relationship was found between the d-spacing of the actin/myosin fibril spacing (SAX1 and SAX2) and the cross sectional area of the rhombohedral unit cell (Cell area) and shear force after 1 and 5day ageing. There was a positive relationship between IMF and a SAXS Fat area measure. There was a muscle site effect on SAX1, SAX2 and Cell area, with the cranial site having a larger distance between myofibrils. The potential of SAXS as a powerful research tool to determine not only the structural components of ovine tenderness, but also the fat content related to IMF is evident.

A pen feeding study was conducted using 10 month old Poll Dorset × Merino ewe lambs to test the effect of perennial wheat forage on growth rates and carcass characteristics in comparison to annual wheat forage. Individual lambs (n = 48) were fed one of four diets, namely perennial wheat (PW), annual wheat (W), perennial wheat + lucerne (alfalfa) (PW + L) or annual wheat + lucerne (W + L). Lambs were monitored for 28 days during which daily forage quality, forage mineral content, feed intake and weekly liveweight change were recorded. At the completion of the feeding period all lambs were slaughtered in a commercial abattoir. At 24 h post-slaughter the left hand side longissimus lumborum muscle (LL) was removed and assessed for quality attributes. Feed intake increased over the 28 days with W fed lambs eating a greater amount compared to PW fed lambs. The addition of lucerne to the cereal forage (PW + L and W + L) increased feed intake (P

Beef ageing (in vacuo) for tenderisation and flavour development may be accelerated by favourable temperature-time combinations (TTCs), however the effect of such manipulations on volatile organic compounds (VOCs) that are generated during cooking, is unknown. We compared VOCs from grilled beef longissimus lumborum muscle samples which had been subjected to different TTCs. The TTCs consisted of combinations of temperatures (~ 3, 5, or 7 °C) and ageing time periods (6, 8, 10 or 12 d); as well as control samples, which were held at 0-2 °C for a total of 14 d. Sensory quality attributes of these same samples were measured by untrained consumer panellists. Generally, it was found that TTCs had negligible effects on grilled beef VOCs and were comparable to controls. Furthermore, many VOCs were significantly related to flavour intensity, flavour liking and overall liking. These findings support the use of TTCs as a viable means to accelerate the rate of beef ageing without compromising quality.