Non-Alcoholic Beer Production Using Ohmic Heating-Assisted Vacuum Distillation Method

In this study, non-alcoholic beer was produced with an ohmic heating-assisted vacuum distillation system (ODVD) and vacuum rotary distillation (VDD). The processes were conducted at three vacuum pressure levels (100, 150, and 200 mbar). Corresponding operating temperatures were 50, 58, and 67°C for the VDD system, while the ODVD system operated at in-situ-ohmic heating without an external heating medium. In ODVD, three voltage gradients (15, 20, and 25 V/cm) were applied. The two systems were compared in terms of processing time, energy efficiency, aroma profile, antioxidant capacity (ABTS, DPPH, TAC, FRAP), total phenolic (TPC) and total flavonoid content (TFC), vicinal diketone (VDK), pH, color, and bitterness value. The ODVD system showed significantly shorter processing times and energy efficiency than VDD. While the pH values of dealcoholized beer increased slightly compared to the original beer, color and bitterness values were higher in VDD samples. Aroma compounds such as ethyl acetate, isoamyl acetate, and ethyl caproate were lost during both processes. Overall, the findings demonstrate that ODVD is a promising and energy-efficient alternative for the production of non-alcoholic beer, with comparable product quality to VDD.