Concentration (°Brix) Measurement of Sugar and Sugar Substitutes call_made


A globally well known Swiss producer of beverages was one of the first Swiss companies subject to the stringent quality and safety requirements of the International Food Standard (since 2004) and has been certified according to FSSC 22000:2011 since 2012. Since the end of 2005, the company has been operating one of the most modern, cold aseptic bottling plants in the beverage industry. The beverages do not contain any preservatives nor are they subject to prolonged heating – the drinks are only heated gently for a short time in order to conserve the valuable ingredients.

A key factor for product quality is to ensure that the required concentration of sugar or sugar substitutes in the carbonated soft drinks is maintained exactly.

Thus, the concentration is monitored by two PIOX R Process Refractometers which are installed directly in the production stream before and after the flash pasteurisation. The refractometers that had priorly been installed for this purpose worked according to the critical angle principle. They quickly showed a measurement drift due to deposit formation on the prism and could not cope with the high accuracy requirements. Further, in order to ensure the required °Brix value, which is also to be maintained in the low-calorie soft drinks, the reproducibility of the measurement results must be better than 0.01 °Brix - a precision that was difficult to reach with the previously used critical angle refractometers.

FLEXIM’s PIOX R transmitted light Process Refractometer was the only process analyser that could achieve the required measurement precision in the process.
In addition, PIOX R reliably detects the media change during the insertion and extraction process, in other words when switching between beverage production and the cleaning cycle (CIP).


  • Continuous concentration measurement directly in the process, ensuring permanent quality control
  • Reliable determination of the separation layer between product and water or cleaning media when switching between production and flushing phase (CIP)
  • Reliable, drift-free and long-term stable measurement using the transmitted light method
  • High measuring accuracy, exceptionally high reproducibility
  • Installation possible directly in main current, no bypass necessary
  • Detection of deposit formation by monitoring the signal amplitude and thus automatic triggering of cleaning intervalls