A system for detecting a hydrogen peroxide (H2O2) concentration in a cold aseptic filling system that uses a peracetic acid (PAA)-based cleaning solution is shown and described. The system includes a conductivity sensor configured to receive the PAA-based cleaning solution and to provide a signal representative of the electrical conductivity of the PAA-based cleaning solution. The system further includes a controller configured to receive the signal representative of the electrical conductivity of the PAA-based cleaning solution and to compare the signal to a threshold value associated with a setpoint H2O2 concentration.
