The freezing duration and the number of freeze-thaw cycles influence the near infrared spectra of ageing beef muscles

The aim of this study was to investigate the effect of the freezing duration and the number of freeze-thaw cycles on the near infrared (NIR) spectra of ageing beef. Freezing duration was tested on the Serratus ventralis muscle with durations of 3, 6, and 12 months. The effect of four freeze-thaw cycles was tested on the Infraspinatus and Rhomboïdeus muscles. Our results obtained by the Analysis of Variance Simultaneous Component Analysis (ASCA) show that the NIR spectra of muscle were impacted by the freezing duration and the number of freeze-thaw cycles. However, these effects were non-linear and varied slightly according to the muscle studied. ASCA analyses showed that the freezing duration and the number of freeze-thaw cycles affect NIR wavelengths mainly related to C-H, O-H, and N-H bonds, which are known to be associated with proteins, lipids, and water. This study showed that the NIR spectra of ageing beef were sensitive to the freezing duration and the number of freeze-thaw cycles. • NIR spectra of ageing beef were sensitive to the freezing duration • The number of freeze-thaw cycles of ageing beef influences NIR spectra • The effect of freezing duration and freeze-thaw cycles number was not linear • Freezing impact on NIR spectral region is mainly related to C-H, O-H, and N-H bonds