The present invention relates to the system (20), apparatus, and method for controllably mixing a concentrate with a dilution substance using closed-loop feedback in order to improve the resultant substance. The conductivity of a diluted substance is sensed in order to provide feedback information for adjusting dispensing of a concentrate used to produce the resultant or diluted substance. The system includes a conductivity sensor (30), a controller (38) and a conductivity sensing circuit (48) such that the dispensing of the concentrate is controllably adjusted to maintain the resultant beverage within a desired concentration range based on conductivity sensing. The present invention also includes a method for sensing the conductivity of the resultant beverage and adjusting the dispensing of concentrate in response to the conductivity of the resultant beverage.