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The application of individual spectroscopic techniques for meat analysis has been widely explored. Attempts to fuse data from multiple spectroscopic instruments for meat analysis are still lacking. Comparative assessment of the performance of mid infrared (MIR), near infrared (NIR) and Raman spectroscopy to estimate fatty acid (FA) composition in processed lamb was investigated. The acquired data from these individual techniques were then utilised in estimating similar parameters using a multi-block partial least square data fusion approach. Model performance was assessed with respect to the determination coefficient and ratio of predictive deviation upon cross-validation of the model. The fused data had slight improvements for the prediction of four FA parameters including MUFA, C18:0, C18:1 c9 and C9, t11- CLA), suggesting possible information enhancement with use of multiple instruments. However, MIR offered better predictability (RPD values) across the FA parameters considered.

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The implementation of Raman and infrared spectroscopy with three data fusion strategies to predict pH and % IMF content of red meat was investigated. Raman and FTIR systems were utilized to assess quality parameters of intact red meat. Quantitative models were built using PLS, with model performances assessed with respect to the determination coefficient (R2), root mean square error and normalized root mean square error (NRMSEP). Results obtained on validation against an independent test set show that the high-level fusion strategy had the best performance in predicting the observed pH; with RP2 and NRMSEP values of 0.73 and 12.9% respectively, whereas low-level fusion strategy showed promise in predicting % IMF (NRMSEP = 8.5%). The fusion of data from more than one technique at low and high level resulted in improvement in the model performances; highlighting the possibility of information enhancement.

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With increasing demand for fast and reliable techniques for intact meat discrimination, we explore the potential of Raman spectroscopy in combination with three chemometric techniques to discriminate beef, lamb and venison meat samples. Ninety (90) intact red meat samples were measured using Raman spectroscopy, with the acquired spectral data preprocessed using a combination of rubber-band baseline correction, Savitzky-Golay smoothing and standard normal variate transformation. PLSDA and SVM classification were utilized in building classification models for the meat discrimination, whereas PCA was used for exploratory studies. Results obtained using linear and non-linear kernel SVM models yielded sensitivities of over 87 and 90 % respectively, with the corresponding specificities above 88 % on validation against a test set. The PLSDA model yielded over 80 % accuracy in classifying each of the meat specie. PLSDA and SVM classification models in combination with Raman spectroscopy posit an effective technique for red meat discrimination.

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OBJECTIVE: The aim of this study is to characterize the impact of additional electrical stimulation (AES) and various pre-rigor holding temperatures (for 3 h) on the ageing-potential of hot boned bovine M. longissimus lumborum (LL). METHODS: Paired LL loins from 12 bulls were hot-boned within 40 min of slaughter, immediate AES applied and subjected to various holding temperatures (5°C, 15°C, 25°C, and 35°C) for 3 h. RESULTS: AES did not accelerate the rate of rigor attainment, but the 3 h pre-rigor holding temperature did. Shear force values decreased as the pre-rigor holding temperatures increased. AES and holding for 3 h (at 25°C) resulted in higher water-holding capacity. CONCLUSION: Data confirmed that AES did not influence the various meat quality parameters in the present study, but pre-rigor holding temperature (25°C) alone or in combination with AES resulted in superior meat quality.

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Despite various direct transmethylation methods having been published and applied to analysis of meat fatty acid (FA) composition, there are still conflicting ideas about the best method for overcoming all the difficulties posed by analysis of complex mixtures of FA in meat. This study performed a systematic investigation of factors affecting a one-step method for quantitative analysis of fatty acids in freeze-dried animal tissue. Approximately 280 reactions, selected using factorial design, were performed to investigate the effect of temperature, reaction time, acid concentration, solvent volume, sample weight and sample moisture. The reaction yield for different types of fatty acids, including saturated, unsaturated (cis, trans and conjugated) and long-chain polyunsaturated fatty acids was determined. The optimised condition for one-step transmethylation was attained with four millilitres 5% sulfuric acid in methanol (as acid catalyst), four millilitres toluene (as co-solvent), 300 mg of freeze-dried meat and incubation at 70 °C for 2 h, with interim mixing by inversion at 30, 60 and 90 min for 15 s. The optimised condition was applied to meat samples from different species, covering a broad range of fat content and offers a simplified and reliable method for analysis of fatty acids from meat samples.

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The objective of this study was to determine the effect of two different freezing rate then thaw-aging regimens on the quality attributes of lamb loins. The loins were randomly allocated to one of five different freezing/thawing/aging regimes: fast-(FF1A0) and slow-(SF1A0) frozen only; fast-(FF1A2) and slow-(SF1A2) frozen then thaw-aged for 14 days; aged for 14 days never frozen (A2). FF1A2 samples had a significantly higher water-holding capacity compared to the slow frozen regardless of further aging periods. FF1A2 samples had lower (p < 0.05) shear force values than A2 and higher (p < 0.05) water-holding capacity compared to the SF1A2. Fast freezing resulted in more intracellular cryo-damage, whereas slow freezing resulted in extracellular cryo-damage. FF1A0 and SF1A0 samples had lower (p < 0.05) myofibrillar proteins degradation. This study demonstrated that fast freezing then thaw-aging can result in an improved water-holding capacity and tenderness through the minimization of extracellular ice crystal formation, reduction in purge and drip losses, and improved proteolysis in thawed lamb.

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Spectroscopy in the visible near-infrared spectral (Vis-NIRS) range combined with imaging techniques (hyperspectral imaging, HSI) allows assessment of chemical composition, texture, and meat structure. The use of HSI in the meat and food industry has observed a significant growth in the last decade, yet its use for assessment of meat it is not optimal yet. The application of HSI for assessment of meat is reviewed with focus on its ability to capture meat unique chemical and structural characteristics. While HSI is widely used for assessment of chemical composition, a limited number of evidences on its ability to handle the effect of different sources of variation on the assessment is found. The use of spatially resolved spectroscopy has been able to detect structural information related to animal background, muscle type, rigor process and ageing. Similarly the use of texture features seem to capture unique characteristics of meat.

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Wagyu beef products are marketed as luxury goods to discerning consumers and the lipid content and composition are important drivers of wagyu product value. Wagyu beef is an extensively marbled meat product, well characterised for its tenderness and flavour. In New Zealand, pasture-fed Wagyu-dairy beef production is increasing to meet demand for ultra-premium meat products. Important for these characteristics is the composition of lipid species and their distribution across the carcass. The aim of this study was to analyse the distribution of fatty acids and phospholipids in 26 table cuts, nine co-products and three fat deposits of carcasses from New Zealand pasture-fed Wagyu-dairy cross beef carcasses (n = 5). Phospholipid and fatty acid levels varied across different cuts of the carcass, but typically cuts with high levels of phospholipids also had high levels of omega-3 fatty acids and low levels of saturated fatty acids. This work will be used in the future to examine the potential health aspects of pasture-fed Wagyu beef.

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