Near infrared spectroscopy measurement and kinetic modeling for physiochemical properties of tabtim fish (hybrid tilapia oreochromis sp.) Fillets during chilling storage

Anotace: This research is aimed to investigate the physiochemical properties of Tabtim fish fillets [pH, moisture content, water holding capacity (WHC) and texture profile analysis] during storage at 0, 5, and 10ºC for up to 18 days. Near infrared spectroscopy (NIR) was used as a nondestructive measurement and kinetics was also applied for determining the quality changes. Results showed that the pH value increased with an increase of storage time and storage temperature (P≤0.05) while the hardness and WHC were decreased as a result of increasing time and storage temperature (P≤0.05). Change in pH, hardness, gumminess, and chewiness during storage can be described by zero- or first-order reactions. NIR spectra of fish fillets (180 samples) were collected in the reflectance mode with both the short-wavelength region (700-1000 nm) and long-wavelength region (1000-2500 nm). A partial regression model with cross validation was created. The models for pH, hardness, adhesiveness, and gumminess demonstrated that the value for the determination coefficient of validation ranged from 0.61-0.73 while the standard error of prediction was 0.14 for pH, 2.58 N for hardness, 0.21 N.mm for adhesiveness, and 1.68 N for gumminess. The model developed using NIR could predict pH, hardness, adhesiveness, and gumminess as basic for a screening test.