The potential of laser-induced breakdown spectroscopy for industrial at-line monitoring of calcium content in comminuted poultry meat

The presence of bone particles, and hence the calcium content, is a key quality parameter for mechanically separated poultry meat (MSM). A method for fast at-line monitoring of the calcium content in MSM during production is therefore requested by the industry. Laser-induced breakdown spectroscopy (LIBS) is an interesting technique in this regard because it is fast and potentially enables direct detection of minerals in a sample with minimal sample preparation. Nine commercial MSM samples, representing the common range of calcium contents in MSM, a hand-deboned sample and minced poultry meat were measured by LIBS using sample preparation suitable for an industrial at-line monitoring setting. In the spectra obtained, emission lines from sodium, potassium and calcium were identified. Using inductively coupled plasma optical emission spectrometry (ICP-OES) as the reference method, and partial least squares regression (PLS) as calibration model, including three calcium lines adjusted by potassium, it was possible to separate samples according to three calcium levels with LIBS. Very low (<20 mg/100 g Ca), intermediate (20-90 mg/100 g Ca), and high (>90 mg/100 g Ca).