Using a refractometer in the food industry, as well as in beverages and pharmaceuticals, offers real-time inline concentration measurement and is the key to continuous quality control and efficient production. With its food & beverage refractometer PIOX R721, FLEXIM offers for this purpose the most powerful measuring instrument of its kind.

Whether the degree of ° Brix needs to be monitored during soft and fruit drink production or concentration levels of ascorbic and cetogulon acid during Vitamin C manufacturing have to be supervised, PIOX R721 outputs the desired values with an accuracy of 0.1%.

Pharmaceutical refractometer PIOX R721 is highly hygienic by itself. With its stainless steel housing, the sapphire prism and completely engineered with no allowance for dead spaces, potential bacterial contamination can be ruled out at any time.

PIOX R721 can be integrated into the process via Varivent or Tri-clamp compatible flanges.


  • Highly accurate, reliable and hygienic real-time concentration measurement solution (° Brix, Oechsle, Plato, sugar content and more)
  • No measurement drift due to potential plate out as often indicated when employing conventional critical angle refractometers in food processing
  • Quality assurance due to real time product monitoring - costly laboratory testing becomes obsolete
  • Ready for Advanced Meter Verification


Technical Facts

Measuring quantities
Refractive index and refractive index at standard temperature, fluid temperature, concentration g/l, mass and vol.%, density and density at standard temperature, scale values for example °Brix and °API, additional quantities programmable
Measurement range
nD: 1.3 ...1.7, °Brix: 0 ...100
Measurement accuracy
nD: 0.0002 (corresponds to: 0.1 °Brix, 0.1 w%)
nD: 0.00002 (corresponds to: 0.01 °Brix, 0.01 w%)
Diagnostic values
-20 °C ... (+130 °C) +150 °C
Media temperature
150 psi; on request 300 psi
(depending on process connections)
Fluid pressure
Sensor: IP67, FM Class I Div. 2
Transmitter: IP65, FM Class I Div. 2
Degree of protection
Sensor R500: IP67, ATEX (IECEx) zone 0,/1
Transmitter R721: aluminium or stainless steel enclosure, IP66, ATEX (IECEx) zone 2
Wetted parts, materials
Stainless Steel 316L (1.4404)
Housing Material
Stainless Steel 304 (1.4301)
Process connection
Compatible to Varivent or Tri-clamp connection
Advanced Meter Verification (AMV)