Accreditation of in-abattoir Dual Energy X-ray Absorptiometry scanning apparatus to predict lamb carcass composition in Australia

Dual Energy X-ray Absorptiometry (DXA) scanners operating at abattoir processing speeds are currently installed in six sheep meat abattoirs around Australia, predicting carcass composition as estimates of computed tomography (CT) determined fat %, lean %, and bone %. This study tested an updated bone-detection algorithm for these DXA scanners. This algorithm improved the precision of prediction for carcass fat% and lean%, but most notably for bone % (R2 = 0.92, RMSE = 0.61 %), compared to the previous algorithm (R2 = 0.51, RMSE = 1.57 %). This was due to improved allocation of bone-containing pixels, resulting from the inclusion of tissue thickness in the bone-detection equation. In a second experiment, the predictions from this new algorithm, along with an automated phantom calibration technique, were assessed relative to their ability to meet the AUS-MEAT accreditation accuracy standards required for predicting CT determined carcass fat%, lean%, and bone%. The DXA met these standards for predicting fat % (range 10.9 % - 37.1 %), lean % (range 49.0 % - 66.2 %), and bone % (range 11.6 % - 25.0 %), across three weight bands of light carcasses (<22 kg), mid-weight carcasses (22-28 kg), and heavy carcasses (>28 kg). This work allowed for the accreditation of DXA, enabling its predictions of carcass composition to be used for trading sheep carcasses in Australia. The accuracy of these predictions far exceed those provided by the historical industry measure of GR tissue depth, and hot carcass weight.

Exploration of methods for lamb carcass yield estimation in Canada

Different approaches were evaluated to improve the accuracy of carcass yield predictions of Canadian lamb carcasses using manually obtained measurements and dual-energy X-ray absorptiometry (DEXA). Several linear carcass measurements were obtained from a population of commercial lamb carcasses representative of the variability in Canadian slaughter plants (n = 155). Carcass measures were categorized into four sets according to when each measure could be obtained in the slaughter process. Each set of carcass measurements were subjected to stepwise regression and used to develop models for the estimation of lean meat and saleable yield percentages. Tissue depth measures (at the GR site) explained 44% of variation in lean meat yield in hot carcasses and 53% in cold carcasses. When additional parameters were included with cold GR, the regression model explained 61.9% of the variability in lean meat yield. Saleable yield predictions were less accurate (R2 < 0.40); the greatest degree of variability was predicted when the model included ribeye area (R2 = 0.39). The DEXA scans obtained on carcass sides were able to predict about 78% of variability in carcass lean meat yield and 91% of fat content. This information could be used by the lamb meat industry to establish new carcass classification systems based on more accurate lean meat yield values.

Processing technology changes in the Australian sheep meat industry: an overview

Over the last 20 years the Australian sheep industry, particularly the lamb meat sector, has undergone a major change in focus such that consumer requirements are a paramount determinant for production and processing developments. As a result automatic accurate methods of measuring carcasses for traits like fatness and meat yield have been important to aid a reduction by industry in carcass fat levels in line with domestic and international consumer demand. This occurred while carcass weight increased due to a range of genetic and production factors implemented on-farm. Further to this in the last 5–7 years there has been a dramatic increase in the adoption of electrical technologies based on new methodologies with a shift in focus onto eating quality. Underlying this new approach was the electrical stimulation of individual carcasses on segmented electrodes in a dose-responsive way with electricity that has short pulse widths and low to medium voltages and is thus much safer than the original high voltage systems. This technology allowed stimulation units to be fitted into abattoirs where this was not previously possible and validation showed that the technology could reduce toughness in lamb destined for the domestic market and some export markets. More recent technology to stretch and shape cuts shows promise for improving both the quality and product range from sheep and lamb carcasses. The industry continues to focus on meat quality and has shown a significant increase in exports, while maintaining per-capita domestic consumption at record retail prices. This indicates an industry where research investment across the board has shown significant returns.

Current and future issues facing red meat quality in a competitive market and how to manage continuous improvement

This paper discusses current and future issues facing lamb and beef meat quality and proposes strategies to manage quality improvements into the future. Based on survey data of Australian consumers and whole supply chain profit drivers, it is argued that the three most important quality areas for future research are lean meat yield, eating quality and human nutritive value. These areas have complex biological interactions, both antagonistic and complimentary, which require careful management so as to produce the best outcome for industry and the consumer. It is argued that the best way forward is to undertake collaborative research that encompasses industry production, meat science and genetics simultaneously. The case study of the Australian lamb industry is used as a suggested model for future progression, whereby a large breeding program forms the central focus of numerous research and delivery activities. Another issue raised is the need for strong and cost-effective industry systems that are able to effectively utilise outcomes from genetics, lean meat yield and eating quality to deliver the research results.