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[EN] Dielectric spectroscopy in microwave and radiofrequency region is an emerging control technique used to obtain information about the transformation of biological systems. In microwave region, the main interaction is produced with different food constituents and water molecule. In this context, the dielectric properties were analyzed during beer production in order to improve beer quality. There were also analyzed the most important physical and chemical properties of beer through the process. Good correlations were found between loss tangent at 10 GHz and the ethanol and sugars concentration. Therefore, this technique can be used as a fast, accurate and non-destructive control method of beer production. (C) 2013 Elsevier Ltd. All rights reserved., The authors acknowledge the financial support from the Spanish Ministerio de Ciencia e Innovacion throughout the project AGL2011-30096. Author M. Castro-Giraldez thanks the Campus de Excelencia Internacional VLC/CAMPUS for their support. Author J. Velazquez-Varela thanks the Consejo Nacional de Ciencia y Tecnologia (CONACyT) of Mexico for their support.

Salting treatment is a common operation in high quality meat production, which main objectives are to conserve the product by water activity depression and to transform the sensorial properties of fresh meat to the final meat products (like salted, cured, dried or cooked meat products). One of its main problems is the difficulty to control the simultaneous water and salt fluxes into the product and the protein fibers transformation throughout process. Water and salt transport during osmotic treatment of pork meat (Longissimus dorsi) immersed in saturated salt solution, were investigated by using a thermodynamic approach. In this work the effect of rigor mortis state in the salting treatment has been demonstrated. A thermodynamic model in non-equilibrium has been developed for describing the different behaviors involved in salting process.

Salting treatment is a common operation in the production of high quality meat products, one of its main problems is the difficulty to control the simultaneous water and salt fluxes into the product and control the protein fibers transformation throughout process. Dielectric properties of salted porcine meat are strongly related to its structure and composition. Thus, dielectric properties measurement appears as a promising method for controlling on-line the salting process in meat industry. Dielectric spectroscopy studies have been performed on raw and salted Longissimus dorsi pork samples. Dielectric spectra were measured in the frequency range from 500 MHz to 20 GHz by an Agilent 85070E open-ended coaxial probe connected to an Agilent E8362B Vector Network Analyzer immediately after salting process and also 16 h. Salt content, moisture, water activity and volume were also measured. It has been demonstrated that the dielectric properties are a good tool to analyze the share of the added sodium chloride molecules in the muscle tissue during the salting treatment (bounded and solved ions).