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The main limitation of salting is its extended processing time, mainly caused by the slow diffusion of salt into the muscle tissue. The diffusion process can be accelerated by different technologies such as moderate electric fields (MEF) and CO2-laser microperforations. The main objective of this research was to evaluate the implementation of a combined MEF-CO2-laser-microperforation treatment on the acceleration of the salting process in Atlantic salmon (Salmo salar) and its influence on the effective diffusion coefficient (Deff). Salmon fillets were cut in cylinders. Microperforations at 50 and 100% depth into salmon tissue were produced axially with a 100 W CO2 laser. For MEF treatment an electric field strength of 1 V/cm was used. Salt concentrations along time were analyzed through Fick’s second law and anomalous diffusion models, considering a finite cylindrical geometry. As a result, treatment with micropores-MEF achieved a salt concentration of 3.5% after 4 h, while the control required 12 h to reach the same salt concentration. When both technologies were simultaneously applied, both Deff and final equilibrium salt concentration were increased, thus resulting in a significant reduction in salting time. The mathematical analysis showed good fit through the anomalous, presenting a sub-diffusive (α

A simple method to study the diffusion of a probe molecule into muscle tissue, which considers real composite architecture and anisotropy, was proposed. An anisotropic diffusion study of methylene blue (MB) as a probe molecule into the composite muscle tissue of salmon (Salmo salar) was performed using an image-processing technique. The concentration profile was determined in the middle sagittal plane by considering the muscle fiber orientation angle (θ). The mean value of the angle was θ = 31 ± 1.2°, and the fractional anisotropy values showed an anisotropic behavior for all samples tested. The presence of the discontinuity between muscle and connective tissue was characterized by the distribution coefficient. The simulation using the generalized minimum residual method iterative solver in COMSOL Multiphysics™ software described the anisotropic condition of the tissue with root mean square values of less than 27%. Significant differences were found in effective diffusion coefficient values between the muscle and connective tissue at 2 °C (p-value

Free fatty acid (FFA) release from the in vitro digestion of an emulsion-filled gel using three different particle size distributions and its modeling using the Weibull function and Gallagher–Corrigan model were investigated. To produce the emulsion-filled gel, an oil/water mix was prepared and blended with sodium alginate to finally produce small calcium alginate gel cubes. Three different particle size area distributions were generated by comminuting the cubes applying 5, 10, and 15 cycles of compression/shearing. The particles were intestinally in vitro digested, and the fraction of FFA released was calculated and analyzed using the Weibull function and Gallagher–Corrigan model. The FFA release showed a sigmoidal behavior for the three particle distributions; the Weibull function did not show a good fit. The Gallagher–Corrigan model presented a good fit to the FFA data, reinforced with a random error distribution. The model parameters were able to explain the kinetic processes related to both surface emulsion release and emulsion release by matrix dissolution. In addition, some parameters were linearly correlated (R2 > 0.99) with particle size, which established a relationship between particle size and the kinetics of release attained during the first stage of the digestion curve.