Desalting of dried salt-cured cod (Gadus morhua L.) without water renewal - 3D imaging of volume change

Summary

Desalting of dried salt-cured cod without water renewal with stirring every 12 h, and in stagnant water, was explored. Products of about 450 g were desalted for 96 h, followed by refrigerated storage in 120 h. During the desalting and subsequent storage, the change in weight, volume, salt-, and water content was calculated. Two different methods for calculation were applied, namely calculating the changes time by time, and by calculating the kinetic constants, k1 and k2, which express the total mass variation by pressure gradients, and the overall pseudo-diffusional and hydrodynamic mechanisms, respectively. A positive correlation between the change in weight, volume, and water content was observed, and these variables correlated negatively with the change in salt content. By calculating changes time by time, a significant difference in weight and salt content of the surface between the two desalting regimens was observed only after 96 h. The kinetic constants did, however, show a significant difference between the two desalting regimens for weight, salt, and water. A positive correlation between the volume and weight was observed irrespective of the desalting regimens. This indicates a future potential in applying an improved 3D imaging as an indicator of the weight changes during the desalting process.