What is the role of flow meters in candy manufacturing?

July 19, 2022 Erwin Broekman (Br-NL)
Flow control in candy manufacturing

What role does Bronkhorst play in candy manufacturing? Well… there is a huge variation in candy available on the market, each brand with its own taste, texture and appearance. These features are often part of the branding of the major confectionery manufacturers. And therefore, it is important that all candy has the right taste, but also the right colouring and texture. This is the part where flow meters come in the picture…

These confectionery manufacturers buy their machines at machine builders (OEMs). One of these machine builders who is specialised in equipment for the food industry, especially in aerating, depositing, forming and mixing of fat creams, chocolate and other masses, is Haas-Mondomix B.V. (part of the Bühler group). I had the opportunity to work with them on a solution, containing ultrasonic volume flow meters, for adding additives (such as flavourings and colourings) into the main stream of the production process of candy.

Application at Haas Mondomix B.V. (part of the Bühler group)
Application at Haas Mondomix B.V. (part of the Bühler group)

What is important when dosing additives?

The equipment Haas-Mondomix B.V. designs for the confectionery industry has to meet strict requirements. Important topics here are:

  • High-quality confectionery products; As confectionery products, such as candy, represent a specific brand it is important that the colour, texture and taste are always the same. So reproducibility in this process is essential. Good reproducibility will result in high-quality confectionery products. 
  • Efficient use of raw materials (colourings, acid and flavourings); Coulouring and flavourings are very costly agents, especially the natural variant. Therefore, a controlled and efficient use of these substances is very much desired. You will save on raw materials and it will also add to a better quality as well.
  • Sanitary design, suitable for food applications; for devices in food applications it is important that they have hygienic design meaning a surface roughness ≤ 0.8 µm and no dead volume.

Ultrasonic flow meter for low flow rates

Ultrasonic flow meters for liquid additives dosing

In the old days, if something went wrong in the candy manufacturing process, poor quality was observed by looking at the candy at a rather late stage, resulting in entire batches of candy that had to be defined as 'second choice'.

Together with Haas-Mondomix B.V., we succeeded in finding a solution to design even more efficient equipment for aerating, depositing, forming and mixing of fat creams, chocolate and other masses.
During a test we used multiple ultrasonic flow meters (Bronkhorst’s ES-FLOW series) to measure the amount of additives - flavourings, colourings and acids - that were added to the main stream of the production process. As these fluids are highly concentrated, only small amounts have to be added. This can be measured with the ultrasonic flow meter, with a flow range up to 1500 ml/min with a precision of +/- 1% Rd.

Depending on the type of candy to be produced, the colourings, flavourings and acids will vary. For one type of candy - a red wine gum, for example - these amounts have to be constant for the entire batch. However, the setup with the ultrasonic flow meter is sufficiently flexible to be used for another type of candy - take a green wine gum - after rinsing in between. In the current process, the ultrasonic flow meter is used for measuring purposes, and sends the measurement values to the PLC.

Read more about the Haas Mondomix B.V. solution in the application note.

Ultrasonic wave technology
Principle of 'ultrasonic wave technology'

How does this ultrasonic flow meter work?

The ES-FLOW flow meter is based on ultrasonic wave technology. Measuring is done in a straight stainless steel tube with a very small internal diameter, without any obstructions or dead spaces. Numerous transducer discs located at the outer surface of the sensor tube create ultrasonic waves by radially oscillation. The flow velocity and speed of sound are calculated by measuring the time difference between the recordings. Knowing these parameters and the exact tube crosssection, the flow meter is able to measure liquid volume flows. It is liquid independent and calibration per fluid is not necessary.

For more information about this ‘ultrasonic wave technology’ check our knowledge base.

Would you like more information on ultrasonic flow meters?

Ask advice ES-FLOW flow meter series