Raman spectroscopy is a highly-selective and non-destructive optical spectroscopy technique which relies on the inelastic scattering of laser light to probe molecular structure. The non-destructive nature of Raman measurements along with the molecular specificity of the spectra make it an optimal technique to monitor manufacturing processes in real time. The use of Raman can facilitate process understanding and allow effective process control, thus helping minimize production errors. We present new insights into a recycled polymer extrusion process.