Measuring massflow and density in milk loading

Application Note | Food & Beverage

  • Loading excess milk onto milk lorries
  • Determining the milk quantity and the separation point between water and milk
  • Precise and cost-effective alternative to weigh bridges


A French Cheese dairy periodically adapts their milk stocks to demand changes. If production has to be reduced, the cheese producer clears their stock quantity of milk by selling it to the market. For this purpose, the milk is directly loaded onto milk lorries (tank trucks) for delivery. During the loading procedure the milk is pushed through the line using water.

Measurement requirements

In order to measure the milk quantity as accurately as possible, the cheese dairy was looking for a suitable measurement solution that was also able to precisely determine the density of the milk loaded (1025…1040 kg/m3 / 64…65 lb/ft3). In this way, the separation point between water and milk couldbe identified so as to ensure only milk was loaded onto the trucks. The cheese dairy considered using either a weigh bridge or a flowmeter complying with their hygienic requirements.

KROHNE Solution

The customer decided in favor of the OPTIMASS 7300 C Coriolis mass flowmeter. The meter allows for continuous measurement of mass flow and density. Once the specified quantity of milk has been reached, the filling process stops automatically. The switchoff point between milk and water is determined by the integrated density measurement. The OPTIMASS 7300 is a single straight tube meter and is manufactured in accordance with the requirements of the food and beverage industry. It is easily drained and cleaned using CIP/SIP.

Customer benefits

Using the OPTIMASS  7300 the cheese dairy benefits form significantly more accurate and reliable measurement of the milk quantities. The integrated density measurement enables the customer to control the milk loading process automatically and without water entering the trucks. The maintenancefree mass flowmeter from KROHNE also offers the customer substantial financial advantages when compared to a weigh bridge which would have caused much higher installation and operating costs.

Products used


Coriolis mass flowmeter for advanced process and custody transfer (CT) applications

  • High accuracy flow measurement of gases and viscous, aggressive or shear-sensitive liquids
  • OIML R117, MI-005; also certified for hygienic use
  • Flange: DN10…100 / ½…4", max. PN100 / ASME Cl 600; various other connections
  • 3 x 4…20 mA, HART®, Modbus, FF, Profibus-PA/DP