Evaluation of the quality of frozen minced red hake: use of fourier transform near-infrared spectroscopy.

The quality of frozen minced red hake was assessed by FTNIR spectroscopy in transmission mode. The region 1530-1866 nm was best correlated to dimethylamine (DMA) concentration, which is an accepted quality index for frozen gadoid fish. Partial least-squares (PLS) analysis showed that this technique predicts the DMA content sufficiently well for quality assurance (SD/SEP > 3). The PLS calibration was equally successful when five narrow spectral regions were chosen instead of the continuous spectrum, indicating that a cheap filter instrument may be developed for industrial use.