Use of Fourier transform-infrared spectroscopy to predict spoilage bacteria on aerobically stored chicken breast fillets

In this research work we explored the potential of mid infrared (MIR) spectroscopy to determine spoilage microorganism on the surface of chicken breast fillets that were kept aerobically at 5 °C for 0, 1, 2, 3, 5 and 8 days, and at 15 °C for 0, 0.5, 1, 2, 3 and 5 days. It is shown that MIR spectroscopy (4000 – 1000 cm⁻¹ range) coupled with attenuated total reflectance (ATR) accessory can be used directly on the surface of meat samples to produce fingerprints. Culture dependent methods were used to determine total viable count (TVC), Pseudomonas, Enterobacteriaceae and Brochothrix thermosphacta on chicken breast fillets at each step of the 2 kinetics. In parallel, MIR spectra were recorded. For each kinetic, partial least square discriminant analysis (PLSDA) results showed 100% of good classifications for the six investigated storage times using 4 PLS factors. PLS regression was carried out to predict the microbial counts from the MIR spectral data. Using PLS model with four factors, good correlation (R² = 0.99) and very small root mean squares error of validation (between 0.01 and 0.97 log cfu/cm²) showed a strong correlation between MIR spectral data sets and the results obtained using traditional methods.