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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.

This study evaluated a range of diffuse reflectance spectroscopic (Vis-NIR spectrophotometers) and imaging (Hyperspectral imaging cameras) instruments for predicting pH, IMF and shear force values of beef in a meat processing pilot plant. A total of 364 beef striploin samples were evaluated and prediction models were developed using PLSR. Models for pH and IMF (except Vis snapshot camera) showed good fit with high Rcv2 (0.29–0.92) and low SECV values. Good prediction accuracy with high Rp2 (0.44–0.90), RPD and low SEP values was also observed. While low values of Rp2 for shear force was observed, the expected curvilinear relationship between predicted values of shear force and predicted values of pH was observed suggesting that spectroscopic measurements were able detect biophysical factors associated to these two attributes. Overall, it can be concluded that diffuse reflectance spectroscopy combined with chemometrics has a great potential to be used as an on/in-line quality monitoring system for the meat processing industry.

Bloodmeal is a protein-rich coproduct of the meat industry and can be converted into a thermoplastic. A solution of peracetic acid can be used to degrade colored compounds in bloodmeal, yielding a light yellow material. This causes an increase in β-sheets in the protein's secondary structure, but the addition of sodium dodecyl sulfate (SDS) and triethylene glycol (TEG) reduced α-helical and β-sheet content, thereby increasing random coils. Without SDS, chains were less capable of folding into these structures, preventing sufficient intermolecular interactions and chain entanglement, leading to low specific mechanical energy input (SME) during extrusion, and poor consolidation. The whiteness of molded samples showed no correlation with SME during extrusion or the degree of consolidation after extrusion; however, they were observed to have a higher level of whiteness with increasing TEG content and should be considered as a secondary process not directly linked to extrusion. Increasing the amount of water during extrusion increased the Young's modulus (E) by facilitating formation of new interactions, while increasing TEG decreased E as a result of plasticization. The action of SDS on destabilizing electrostatic and hydrophobic interactions was beneficial to extrusion, although it had no further effect during injection molding. TEG had virtually no effect on tensile strength, although it was required for flow and facilitated the formation of strong interactions after water had been evaporated during conditioning.

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.

Although not always labeled as such, flexitarianism is the default lifestyle for much of the world, whereby meals based on plant materials provide the bulk of people's calories. The rich nutrition of meat and animal products is often the lynchpin of these diets, even when only consumed occasionally. It provides forms and concentrations of essential proteins, lipids, and micronutrients that are otherwise scarce. However, the production of this meat is resource intensive. It requires large quantities of arable land and water, and typically has lower conversion efficiency of farm inputs to edible outputs compared with crops, poultry, aquaculture, dairy, and eggs. An additional complication is that the quantity of ancillary products produced during slaughterhouse operations is large and underutilized. Each year, approximately 190 million metric tons (MMT) of red meat, including pork, lamb, sheep, veal, beef, and goats are produced globally, half of which will be consumed by less than 25% of the population living in developed countries. With demand for meat expected to exceed 376 MMT by 2030, an increase in the adoption of plant-based diets presents an opportunity for the world to re-evaluate how meat can be sustainably produced, with greater emphasis on animal welfare, nutritional value, product safety, better utilization, and distribution channels. In this article we consider the role meat plays in the modern diet, its production and consumption, opportunities to improve utilization of the animal, the benefits of incorporating a diverse range of red meat into diets, and the strategies that the meat industry should consider in response to flexitarianism.

The effect of sodium dodecyl sulfate (SDS) and triethylene glycol (TEG) on secondary structure of decolored bloodmeal (DBM) during heating was examined via synchrotron-based Fourier transform infra-red spectroscopy (FT-IR) and wide angle X-ray scattering (WAXS). Both additives homogenize secondary structure distribution; SDS increases α-helices and decreases β-sheets and β-turns, while SDS–TEG reduces α-helices and β-sheets and increase random coils. Short heat cycles only change the composition of SDS-TEG treated DBM, implying TEG is responsible for chain mobility. Prolonged heating slowly increases β-sheets and suddenly increases α-helices at 55–75 °C in SDS-TEG treated DBM and 100 °C in SDS-treated DBM. Finally, WAXS shows that structural change due to heating is reversible for SDS-TEG treated DBM.

Thermal analysis can generally be applied to protein-based thermoplastics although standard protein analysis techniques are not always possible to assess chain architecture. Blood (17% protein) from the meat industry can be fractionated or dried to blood meal, which can be converted to a thermoplastic called Novatein. The objective of this paper was to use a consistent methodology to compare different protein fractions from blood to that of blood meal, as well as the plastic produced from it, and how these changes relate to processing. Thermal properties were similar between protein fractions, but there were differences in chain conformation between blood meal, the haem containing fractions (red blood cells and spray dried haemoglobin) and the non-haem fractions (plasma and serum albumin). Blood meal is therefore best considered a single polymer, rather than the sum of its individual fractions. Thermoplastic processing reduces protein aggregation, and this phenomenon is more important than the behaviour of any of the individual proteins.

Bloodmeal can be decoloured using peracetic acid resulting in a material with a pale-yellow colour which only needs sodium dodecyl sulphate, water and triethylene glycol to extrude into a semi-transparent bioplastic. Fourier-transform infrared (FTIR) spectroscopy using Synchrotron light was used to investigate the effect of peracetic acid treatment at various concentrations on the spatial distribution of secondary structures within particles of bloodmeal. Oxidation caused aggregation of helical structures into sheets and acetic acid suppressed sheet formation. Decolouring with peracetic acid led to particles with a higher degree of disorder at the outer edges and higher proportions of ordered structures at the core, consistent with the expected diffusion controlled heterogeneous phase decolouring reaction. The degradation of stabilizing intra- and intermolecular interactions and the presence of acetate ions results in increased chain mobility and greater amorphous content in the material, as evidenced by reduction in Tg and greater enthalpy of relaxation with increasing PAA concentration.

Hydrogen peroxide (HP) can degrade soluble heme, forming yellow or colorless degradation products. Thermal treatment during bloodmeal production changes the conformation of oxyhemoglobin trapping heme in hydrophobic protein regions or forms methemoglobin (metHb) heme which catalytically removes HP. As a result, HP can only degrade a portion of the heme present in bloodmeal leading to poor decoloring. Equilibrium peracetic acid (PAA) solutions can effectively decolor bloodmeal. This work assessed the ability of PAA to decolor bloodmeal and the mechanism by which it occurs. The inability of HP to decolor bloodmeal is determined by the fact that it is unable to permanently degrade metHb heme, or hydrophobically trapped heme. Addition of organic acids to HP led to significant swelling of the protein chains but also to poorer decoloring and lower HP consumption compared to PAA. This suggested that in the case of PAA solutions, where bleaching was facile, the reason PAA solutions are capable of decoloring bloodmeal was due to the action of the PAA molecule against heme, whereas HP and acetic (ethanoic) acid played only minor roles in total bleaching. The decolored protein powder has reduced odor and whiter color, and is suitable for applications such as bioplastics.

Polymers that are compostable and manufactured from renewable resources have gained significant importance in recent years. The objective of this work was to assess the biodegradability of bloodmeal-based thermoplastics in a commercial green-waste composting situation. Materials plasticised with tri-ethylene–glycol lost about 45% of their original mass after 12 weeks composting while unplasticised samples lost 35%. Degradation appeared to have been in two phases; an initial loss of soluble, low molecular compounds in the mesophilic phase followed by degradation of high molecular compounds as the temperature exceeded about 40 °C in the thermophilic phase. It was found that as degradation proceeded materials became more soluble. In addition, plasticised and unplasticized samples contained about 60 wt% moisture after 4 weeks of composting conditioning at 50% relative humidity resulted in approximately 8–10 wt% moisture, unaffected by the extent of degradation. FTIR revealed that proteins underwent hydrolytic cleavage resulting in the formation of primary amines. A significant reduction in combustion temperature was observed, indicative of a reduction in covalent bonding, likely due to shorter chains lengths or less cross-linking.

During the processing of bloodmeal-based thermoplastics (BMT), volatile compounds are released which are odorous and unpleasant. Literature searches revealed that blood components are thermally unstable under oxidising conditions and the presence of iron in bloodmeal (BM) may catalyse the formation of various odorous compounds. The objective of this work was to establish an odour profile for BM as well as BMT prior to extrusion and to determine the effect of oxidative treatment on the resulting odour profile. A comparison of the volatile compounds arising from using BM with those arising from using red blood cells (RB) was carried out using headspace-solid phase micro-extraction–gas chromatography–mass spectrometry (HS-SPME–GC/MS). A total of 23 compounds were identified, 4 of which were products of putrefaction also identified in RB subjected to putrefactive degradation; these were phenol, 4-methyl phenol, indole and methyl indole. In addition, several aldehydes and ketones were identified in BM and RB and may result from thermal, microbiological or auto-oxidative deterioration of the lipids and proteins present in blood during BM manufacture. Oxidative treatment of BM removed some of the compounds that were generated by putrefaction and thermal degradation. Treatment led to an improvement in the perceived odour type and intensity of BM, however, upon conversion to BMT the perceived odour became significantly worse. This malodour was able to be mitigated by the addition of 10–20 wt% activated carbon or greater than 20 wt% natural zeolite, however some malodour reoccurred after storage.

Polymers are known for their susceptibility to degradation as a result of ultra-violet (UV) radiation. In this study, the UV stability of bloodmeal-based thermoplastics (BMT) was evaluated over a period of 12 weeks. Formulations with and without plasticiser were tested and moisture was excluded during accelerated weathering to isolate the effect of UV because of the material’s known sensitivity to moisture. It was found that embrittlement due to loss of water overshadowed the effect of UV degradation. Embrittlement caused the material’s toughness to be reduced by an order of magnitude after only two weeks of exposure, for either plasticised or unplasticised samples. An initial increase in tensile strength was observed after two weeks followed by a steady decline in strength. The elastic modulus reached a plateau after about two weeks of exposure. FTIR did not confirm any chemical changes after 12 weeks exposure and TGA suggested that low molecular mass species were quickly lost during the course of the test. The absence of chemical changes does not suggest resistance to environmental degradation, although the dark pigmentation of bloodmeal may have contributed to the lack of UV degradation. Embrittlement remains a greater concern and requires further attention.

Global consumption of meat products established an enormous and constantly growing industry. By-products generated from this industry have a high biological oxygen demand, and if they are not treated properly, then they can have serious implications for the environment. Meat products, such as fish, chicken, beef, sheep, and pork all result in similar waste products. These include carcasses, intestines, feathers, fish bones and scales, as well as blood. Although these can be seen as waste from the meat producer, they become much more valuable after rendering. A variety of products exist, such as gelatin from hooves, meat-and-bone meal from carcasses and intestines as well blood, feather, and fish meal. These are mainly used as animal feed supplements because of their high protein content, but the nutritional properties vary dramatically, and in some cases, further processing is required. In this chapter the sources and properties of animal-based proteins are discussed of their biological composition as well as their physicochemical properties.

Congruent to a rapidly growing population is the generation of horticultural and agricultural by-products and waste. The modern-day food cycle includes agricultural production, postharvest handling and storage, food processing and packaging, and distribution and retail, ending with consumption and waste disposal. Of these, agricultural production and postharvest handling and storage result in unintended losses and by-products whereas the other steps generally result in food waste. Approximately one-third of the worldwide food production is wasted each year. Although it is most desirable to prevent waste and by-product formation, followed by reuse or recycling, the formation of by-products and waste is inevitable, and management options must be innovative and also meet legislative requirements. However, management options are mostly a compromise between what is viewed acceptable based on legal requirements and local perceptions, and what is deemed technologically and financially feasible.

Bloodmeal decolored with 4 wt % peracetic acid can be extruded into a semi-transparent bio-plastic through the addition of sodium dodecyl sulfate (SDS), water, and triethylene glycol (TEG). TEG is often used to plasticize protein thermoplastic materials because of its ability to form both hydrophobic and hydrogen bonds. Synchrotron-based FT-IR was used to monitor changes in the types of hydrogen bonding occurring in TEG plasticized protein during heating. Heating was found to overcome a portion of the weaker hydrogen bonds found within and between proteins, observed as a blue-shift in the N-H and O-H stretching vibrations occurring at ∼3280 cm−1. TEG was shown to be involved in a larger array of hydrogen bonding environments after heating, evidenced by the broadening of the C-OH stretch around 1076 cm−1, suggesting improved plasticizer-protein interactions. Additionally, these bonds were found to be as strong as the original interactions, observed as a shift in the C-OH peak back to its original wavenumber (∼1076 cm−1) during cooling. Initially, TEG was spatially distributed into distinct plasticizer-rich and plasticizer-poor domains, giving rise to two glass transitions. Heating allowed the migration and uniform dispersion of TEG throughout the material, and merged the two glass transitions into one broader glass transition region. Heating during DSC removed the peak around 60°C corresponding to the enthalpy of relaxation, which is associated with physical aging of amorphous and semi-crystalline polymers. While physical aging occurred during the storage of DBM, in the presence of TEG it occurred to a lesser extent. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42166.