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Yield Improvement : Juice Drinks

To improve process understanding and control in the measurement of sugars in solution in fresh juice drinks, in order to reduce false rejects and raw material giveaway...


INDUSTRY:

Consumer goods – juice drinks

SUPPORT LEVEL:

1 consultant, part time support, 6 months

OBJECTIVE:

To improve process understanding and control in the measurement of sugars in solution in fresh juice drinks, in order to reduce false rejects and raw material giveaway.

RESULTS:

  • New test method developed with test equipment manufacturer
  • Raw material savings of over £1 million per annum

What inspired this manufacturer to pursue this project?

During a problem solving training session (Chartwell’s Fault Tree Modelling methodology for complex technical issues), a client participant asserted that the industry standard refractive test for measuring sugars in solution was neither accurate or repeatable.  The participant used Fault Tree Modelling to establish a set of controlled conditions and proved that the inherent uncertainty lead to false product rejects, along with more than £1 million of material giveaway. This loss had been entirely hidden to the business.

Results of the 6 month project

  • Raw material giveaway losses reduced by more than £1 million per annum
  • The manufacturer of the test equipment released a game-changing test method

PROJECT WORK:

What were the key technical issues that needed to be resolved in order to make a more effective test?

The main technical challenge was to understand the science of refractometry and the difference between theory and real-world observation at a microscopic level.

 

HOW WAS THE TEST SUPPOSED TO WORK?

Sugars in the juice cause the refractive index of the liquid to change by a specific amount.

 

WHAT PREVENTED IT FROM WORKING CORRECTLY?

Temperature: The temperature of the equipment and the sample caused micro convection which affects the refraction of the light.

Sediment: Any solids in the juice would settle on the prism, affecting the level of refraction.

What changes were made in developing a new piece of test equipment?

ACTION:

The team worked with the test equipment manufacturer to develop a working method that was robust for factory operations.

The new equipment filtered the sample and stabilised the temperature, prior to pumping the sample over a lens, taking continuous readings, to produce a repeatable and accurate result more than an order of magnitude better than the previous model.