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.