Processing of Carbonated Beer by Pulsed Electric Fields

The microbiological shelf life of carbonated beer can be extended after being processed by pulsed electric fields (PEFs). Being a nonthermal preservation method, the freshlike taste and the original nutritional value are better retained than with conventional thermal pasteurization (TP). Brewery regulations in Canada do not necessitate the TP of carbonated beer; hence, PEF processing finds a potential application in the beer industry. This paper investigates the applicability of the PEF processing to carbonated beer, particularly through a sealed and pressurized processing chamber. However, due to the inevitable flow of current during the PEF processing, metal ions will be released from the electrodes. The presence of these ions in PEF-processed beer accelerates its aging and may affect the organoleptic stability. Hence, we further evaluate the metal ions released during the PEF processing and their consequent effect, if any, on the taste and the shelf life. It has been found that the released amounts of iron ions are observed to be within the acceptable levels for consumable liquid foods. Untrained participants from the public preferred the PEF-processed beer when compared with thermally pasteurized beer. Trained panelists reported a metallic feeling in the PEF-processed beer corresponding to the presence of metal ions that was detected analytically.