Predicting sodium chloride content in commercial king (Oncorhynchus tshawytscha) and chum (O. keta) hot smoked salmon fillet portions by short-wavelength near-infrared (SW-NIR) spectroscopy

Partial least square (PLS) based short-wavelength near-infrared (SW-NIR) prediction models for salt content in commercial hot smoked fillet portions of king or Chinook (Oncorhynchus tshawytscha) (N=140; 212–468 g) and chum (O. keta) salmon (N=120; 137–356 g) were developed. Spectra were collected in the diffuse reflectance mode (600–1100 nm). The total salt content ranged from 1.66 to 5.95% w/w for king and 2.15 to 5.69% w/w for chum salmon. The moisture ranged from 50.7 to 71.6% w/w for king and 55.5 to 69.7% w/w for chum salmon. An optimal PLS model for salt required eight latent variables for king salmon (R²=0.83, SEP=0.32% w/w) and eight latent variables for chum salmon (R²=0.82, SEP=0.25% w/w).