Continued development of a tool to measure intramuscular fat of Australian lamb carcases in commercial situations.

Despite the importance of intramuscular fat (IMF) to eating quality, as yet no methodology has been widely adopted by the whole of industry in Australia to measure it routinely. Thus, a study was conducted to investigate the potential for a Near Infra-Red (NIR) device to predict the IMF content of the loin from spectra collected on the topside which is externally located on a hanging carcase and therefore easily accessible. To this end, NIR spectra were collected from topsides (m.

Validation of Raman spectroscopic models to verify the origin of Australian beef grown under different production systems.

Verification of beef production systems and authentication of origin is becoming increasingly important as consumers base purchase decisions on a greater number of perceived values including the healthiness and environmental impact of products. Previously Raman spectroscopy has been explored as a tool to classify carcases from grass and grain fed cattle. Thus, the aim of the current study was to validate Partial Least Squares Discriminant Analysis (PLS-DA) models created using independent samples from carcases sampled from northern and southern Australian production systems in 2019, 2020 and 2021.

Internal endpoint temperature (level of cooking doneness) effects on the fatty acid and mineral profiles of grilled lamb m. longissimus lumborum.

This study compared the fatty acid and mineral concentrations of lamb meat that was prepared to different levels of cooking doneness. Ten m. longissimus lumborum were each sectioned into 4 slices that were randomly assigned to be uncooked or grilled to an internal end-point temperature of 60 °C (rare), 71 °C (medium), or 77 °C (well done).

Preliminary investigation into the prediction of indicators of beef spoilage using Raman and Fourier transform infrared spectroscopy.

The objective of this study was to assess the potential to predict the microbial beef spoilage indicators by Raman and Fourier transform infrared (FT-IR) spectroscopies. Vacuum skin packaged (VSP) beef steaks were stored at 0 °C, 4 °C, 8 °C and under a dynamic temperature condition (0 °C ∼ 4 °C ∼ 8 °C, for 36 d). Total viable count (TVC) and total volatile basic nitrogen (TVB-N) were obtained during the storage period along with spectroscopic data.

There is no relationship between lamb particle size and consumer scores for tenderness, flavour, juiciness, overall liking or quality rank.

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.

Assessing chemometric models developed using Raman spectroscopy and fatty acid data for Northern and Southern Australian beef production systems.

A total of 960 beef carcases from northern and southern Australian production regions were assessed by examining the subcutaneous fat. Carcases from four different production systems within each region were assessed, by Raman spectroscopy and the fatty acid composition determined to develop models that best classified the various production systems. As a result, 12 Partial Least Square Discriminant Analysis models were developed.

The effect of perennial and annual wheat forages, fed with or without lucerne, on the fatty acid profile and oxidative status of lamb meat.

The current study investigated the fatty acid profile and oxidative status of the meat from lambs that were fed a novel perennial wheat or a conventional annual wheat, either as a cereal monoculture or lucerne biculture. Twelve lambs were assigned to each of the four dietary treatments (48 lambs in total) and held within individual pens for the duration of the 28 day feeding study. Lambs were slaughtered and the (LL) and (SM) muscles analysed.

The quality and mineral composition of the longissimus lumborum and semimembranosus muscles from lambs fed perennial or annual wheat forage with or without lucerne.

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.

Partial least squares and machine learning for the prediction of intramuscular fat content of lamb loin.

Given the paucity of lamb carcase grading tools, there is a distinct need for the development of rapid, non-destructive grading tools for Australian lamb carcases, particularly fat content given its importance to meat and eating quality. The aim of the current study was to determine the potential for Near Infrared (NIR) spectroscopy to predict IMF using Partial Least Squares (PLS) and machine learning analysis methods. As such, 299 lamb loins were measured using a NIR fibre optic device, a sample was excised for Soxhlet determination of IMF content and prediction models were created using either PLS or machine learning analyses methods.

Intramuscular fat prediction of the semimembranosus muscle in hot lamb carcases using NIR.

The aim of the current study was to identify whether changes in pH or temperature during the development of rigor mortis influence spectral quality and thus the prediction of intramuscular fat (IMF) in hot lamb carcases. Semimembranosus muscles (SM) of 75 lamb carcases were measured pre-rigor 3 times (Runs 1-3) using a near infrared (NIR) spectrometer with muscle pH and temperature also recorded. Calibration models for the prediction of IMF showed that spectra measurements taken at Run 2 (R = 0.

Preliminary investigation for the prediction of intramuscular fat content of lamb in-situ using a hand- held NIR spectroscopic device.

Intramuscular fat (IMF) content is critical in the determination of eating quality. At present the Australian lamb industry has no ability to measure IMF as carcases are not split and processing speeds of up to 15 animals per minute prohibit the use of traditional methods. Consequently, the potential for a hand-held Near- Infrared (NIR) device to predict the IMF content of lamb topside in-situ was investigated.

Preliminary investigation of the use of Raman spectroscopy to predict beef spoilage in different types of packaging.

In this study, pH, meat color analysis, microbial counts and Raman spectroscopic data were obtained from beef steaks stored at 4 °C for up to 21 days using two different packaging methods: vacuum (VP) and modified atmosphere packaging (MAP). Models using partial least square regression (PLSR), indicated that Raman spectroscopy was able to predict total viable counts (TVC) and lactic acid bacteria (LAB) measured at 21d post mortem (TVC in VP: R = 0.99, RMSEP = 0.

Preliminary investigation into the use of Raman spectroscopy for the verification of Australian grass and grain fed beef.

Australian grass and grain-fed beef products attract premium prices at sale and several beef processors market beef underwritten by production system claims. This preliminary investigation assessed the feasibility of using Raman spectroscopy to detect differences in the chemical composition of subcutaneous fat from cattle raised in extensive and intensive production systems. Raman spectra, fatty acid composition, β-carotene composition and objective colour measurements were measured on 150 grass and 150 grain-fed cattle.

Assessment of a probe to measure fat depth of lamb carcases.

Despite the research to ensure Australian prime lamb carcases remain a premium meat, there are no objective carcase assessment tools which enable economic incentives to be translated to producers of high meat yielding lambs. Consequently, a probe developed in Iceland, the Icemeat probe, was investigated as a tool for measuring the tissue depth at the Greville (GR) site. To this end, 1087 lambs were measured at two abattoirs over a period of 4 months using the device and a GR knife on every lamb.

Nutritional composition of lamb retail cuts from the carcases of extensively finished lambs.

Despite the value of key nutritional components of lamb to human health, a large scale literature review recently highlighted the lack of nutritional information for value added lamb retail cuts which suit modern consumers. Consequently, the nutritional composition including proximate analysis, fatty acid and mineral composition of 5 lamb retail cuts from 25 commercially produced extensively finished lambs was investigated. Overall, this research indicated that there was variation in nutritional components between these cuts, particularly for nutritional traits which are important for human health including zinc, iron, total fat and protein as well as fatty acids including EPA, DHA, total saturated fatty acids and total polyunsaturated fatty acids.

Investigation of chemical composition of meat using spatially off-set Raman spectroscopy.

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.

Australian Lamb Meat - The Response to Societal and Ethnic Influences.

Lamb has long been considered a traditional meal within Australia; however as consumer preferences have changed since the 1950's, consumption of lamb has decreased from the 1980's. This is the result of changing societal roles, particularly for females, decreasing household sizes and increasing awareness of the impact of food choices on human health. Since the 1980's improvement of farm practices and increases in genetic gains has addressed part of this decline by increasing the amount of lean meat and decreasing fat in lamb retail cuts.

Preliminary investigation of the use of Raman spectroscopy to predict meat and eating quality traits of beef loins.

A preliminary investigation was conducted to determine the potential for a handheld Raman spectroscopic device to predict sensory traits determined by an untrained consumer panel. Measurement of 45 beef loins (M. longissimus lumborum) was conducted using a 671nm handheld Raman spectroscopic device.

The effect of lamb carcase weight and GR depth on the production of value-added cuts - A short communication.

Times for the progressive breakdown of 95 lamb carcases were recorded to determine the impact of carcase weight and GR tissue depth on the time and therefore cost to produce value added retail cuts. Further analysis also assessed the potential to use these carcase traits as predictors of fabrication times. Regression modeling demonstrated there was a limited ability to predict the difference in time to fabricate mid value-added (R=0.

A GR/Impedance probe proves unsuitable for measuring GR depth in Australian lamb carcases.

Multiple studies were conducted at 3 abattoirs to determine the potential of a dual function GR/Impedance probe to measure GR soft- tissue depth (depth at the 12th rib, 110mm from the mid line of the carcase) of typical lamb carcases processed in Australia. Lamb carcases (1016) were measured approximately 25min post slaughter with the probe and a GR knife as the most commonly used measurement. Modelling indicated that variation in the measurement using the probe compared to the measurement using the knife occurred with increasing carcase weight and fatness as well as between different abattoirs.

The effect of forage type on lamb carcass traits, meat quality and sensory traits.

The aim of this study was to evaluate the effect of different forage-types on lamb carcass, meat quality and sensory attributes. Sixty-two, White Dorper lambs finished on bladder clover, brassica, chicory+arrowleaf clover, lucerne+phalaris or lucerne, were slaughtered at a commercial abattoir. At 24h post-mortem, the m.

Are shear force methods adequately reported?

This study aimed to determine the detail to which shear force (SF) protocols and methods have been reported in the scientific literature between 2009 and 2015. Articles (n=734) published in peer-reviewed animal and food science journals and limited to only those testing the SF of unprocessed and non-fabricated mammal meats were evaluated. It was found that most of these SF articles originated in Europe (35.

Prediction of intramuscular fat content and major fatty acid groups of lamb M. longissimus lumborum using Raman spectroscopy.

A hand held Raman spectroscopic device was used to predict intramuscular fat (IMF) levels and the major fatty acid (FA) groups of fresh intact ovine M. longissimus lumborum (LL). IMF levels were determined using the Soxhlet method, while FA analysis was conducted using a rapid (KOH in water, methanol and sulphuric acid in water) extraction procedure.

Predicting meat quality traits of ovine m. semimembranosus, both fresh and following freezing and thawing, using a hand held Raman spectroscopic device.

Complementary studies were conducted to determine the potential for a Raman spectroscopic hand held device to predict meat quality traits of fresh lamb m. semimembranosus (topside) after ageing and freezing/thawing. Spectra were collected from 80 fresh muscles at 24h and 5d PM, another 80 muscles were measured at 24h, 5d and following freezing/thawing.

Raman spectroscopy compared against traditional predictors of shear force in lamb m. longissimus lumborum.

A Raman spectroscopic hand held device was used to predict shear force (SF) of 80 fresh lamb m. longissimus lumborum (LL) at 1 and 5days post mortem (PM). Traditional predictors of SF including sarcomere length (SL), particle size (PS), cooking loss (CL), percentage myofibrillar breaks and pH were also measured.