NIR and Raman as a PAT tool for meat industries: An attempt towards inline lactate content prediction

Lactate levels in blood serve as a key physiological indicator of stress and welfare in animals during slaughterhouse processes. Elevated lactate levels lead to an accumulation of lactic acid in the muscle tissue. This rapid lactic acid production lowers the muscle pH, potentially resulting in undesirable meat quality traits such as pale, soft and exudative (PSE) meat. Optical spectroscopic techniques offer a potential solution for measuring blood lactate levels in real-time as a process analytical technology (PAT) tool in slaughterhouses. This article demonstrates the potential of near-infrared (NIR) and Raman spectroscopy for measuring lactate levels in animal blood after exsanguination. All experiments were carried in real-world slaughterhouse conditions. Furthermore, regression modelling was performed to relate spectra with reference lactate values. The results demonstrated that both and NIR and Raman spectroscopy can predict lactate content in blood in slaughterhouse conditions. Furthermore, the relation of lactate values and final meat quality was also evaluated. The findings from the study can be used to develop PAT systems for continuous blood measurement in slaughterhouse conditions.