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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

Page's equation is one of the most successful empirical equations applied to describe water migration throughout food drying processes. However, when analyzed in detail, the mathematical derivation shows a number of inconsistencies. The hypothesis is that the noteworthy success of Page's equation could be explained by its mathematical similarity with the solution of an anomalous diffusion phenomenon. In addition, the extraordinary success of Page's equation has induced other researchers to search for similar equations, but without a phenomenological comprehension. The objectives are: 1) demonstrate that Page's equation presents some inconsistences in its mathematical derivation; 2) demonstrate that the goodness of fit of Page's equation could be explained by its similarity with the mathematical solution of anomalous diffusion model. A comprehensive examination of Page's thesis was performed by analyzing its theoretical development and experimental data. Also, data reported in the literature were analyzed to test the application of Page's equation, Fick's second law and anomalous diffusion model. This study demonstrates that Page's equation was raised from a misinterpretation of Fick's second law. In addition, anomalous diffusion solution has remarkable similarities with Page's equation, mainly because of the inclusion of time exponential parameter (n). One important outcome from the apple drying data was that n must be constant and independent of temperature, given that n is related with the microstructure of the food matrix. In conclusion, the mathematical solution of anomalous diffusion model through the fractional calculus approach may, in part, explain the goodness of fit of Page's equation to drying data.

The use of technologies that modify food environment for preservation purposes has been extensively studied in the past two decades. Even though technological advances have been made, most of the modified atmosphere packaging (MAP) development has been empirical. In this short communication, a revision of general equations of mass transfer and criteria to design MAP systems was carried out. Mathematical relationships and models to evaluate the flux of CO 2 for the packaging of non-respiring foods are discussed. Data to predict CO 2 uptake for the food, such as solubility and diffusion in refrigerated MAP systems are given.

This paper presents a review of recent developments over the past 10 years that have further advanced the state of the art in improving food safety, quality and manufacturing efficiency in the canned food industry worldwide. The review focuses initially on retort control systems, and the various approaches that have been taken to help canned food processors accomplish on-line correction of unexpected process deviations, the major cause of lost productivity. Important features of each approach are discussed, along with suggested industry applications that would be appropriate for each method. The review also describes recent advances in industrial automation, including new retort systems for flexible and semi-rigid retortable packages, and automated materials handling systems for loading and unloading of batch retorts. The review concludes with a discussion of future trends to be expected in the industry.

Multiway principal component analysis (MPCA) and multiway partial least squares (MPLS) were applied to unfolded fermentation data, and compared for early recognition of problematic behavior in wine fermentations, such as late onset, slow or stuck (premature termination of fermentation). Information from 17 industrial wine fermentations (batches) were used, consisting of measured values for 32 variables, consisting of sugars, density, alcohols, organic acids and nitrogen compounds (including all amino acids). Curve smoothing and curve fitting techniques were applied as necessary pre-treatment of the data. Then, MPCA and MPLS were applied to four different data sets with different combinations of variables to identify the principal components responsible for the problematic behavior. Density, sugars, alcohols and selected organic acids were identified as the principal components. The MPCA application detected only 67% of problematic batches in the data sets after 72 h into the fermentation process. Whereas, the MPLS application was able to predict all of the problematic batches (100%) using the same variables and at the same time into the fermentation process. The ability to identify a problematic fermentation within 72 h can have significant economic impact on operating costs in a commercial winery.