Dosing in food and beverage
The food and beverage industry has strict process requirements to guarantee clean, safe, and repeatable production of a variety of products. Depending on your application, this can be fairly complicated. Consider all of the liquids required to make any given product, each having its own unique physical properties and required rate of application. This can make it quite challenging to ensure precise, accurate metering and control of the liquids used in mixing and dosing systems, especially for the very low flow rates commonly required.
In this blog, we highlight a few food and beverage dosing applications with key considerations for each and then discuss common flow measurement and control solutions.
Food and beverage product examples
Here are just a few examples of food and beverage products which rely heavily on precise dosing to ensure product quality, efficiency, and repeatability.
Modern potato chip production methods, and an increased demand for reduced oil and baked-style chips, mean that chips are exposed to less oil during the production process. As a result, dry seasonings are not able to adhere to the chips as easily. This requires application of small amounts of oil and vinegar to the chips that the dry seasoning can stick to.
Regulation of process conditions are particularly important for the microbiological production of dairy products. To optimize the efficiency of bacterial fermentation, these processes require strict regulation of temperature, pH, nutrients, and gas concentrations. Bacterial growth rates are highly sensitive to these different process conditions, so precision and accuracy of input flow become acutely important.
Breweries must accurately measure degrees Plato (the density of a solution as the percentage of sucrose by weight). The sucrose concentration corresponds to the final gravity of the beer and is therefore used to calculate the end alcohol content of the beer. This ensures your light beer doesn’t accidentally end up a Tripel – what a shame that would be!
Fruit and vegetable concentrates
A similar process is required in the production of fruit and vegetable concentrates. A high quality, minimal waste process is most guaranteed when using a flow device that can provide continuous feedback on the mass flow and density of the product to compare with the brix (sugar content).
Flow technologies for improving dosing applications
The historical way to regulate dosing systems in food and beverage is with pumps. While these get the job done, they are not very accurate. A higher accuracy alternative involves using a flow meter to continually measure output flow and compare it against a setpoint. This feedback loop allows for increased control accuracy, linearity, and repeatability in large scale production environments. Here we discuss three common flow technologies used to regulate the variety of liquids required for dosing in food and beverage processes: electromagnetic, ultrasonic, laminar, and Coriolis.
Electromagnetic flow meters can provide cost-effective solutions and are also compatible with clean-in-place (CIP) and sterilize-in-place (SIP) processes. However, these flow meters rely on the conductive properties of water and can give unreliable readings if you are flowing de-ionized water or liquids containing bubbles.
Ultrasonic flow meters using the Doppler Effect require particulate material or bubbles to reflect the signal, rendering them ineffective with pure, smooth liquids. Conversely, ultrasonic devices using transit time to measure flow can only work with pure fluids. A combination of the two can be employed, but this has additional cost implications as well as issues with reduced accuracy in low flow conditions. An additional perk of ultrasonic flow meters is their ability to measure non-invasively, although they also tend to be sensitive to process vibrations.
Laminar mass flow meters and controllers can be used for fast, accurate measurement and control of fluids with known compositions. Mass flow controllers have fast proportional control valves and quick response times, and some controllers are available with a totalizer function to make precision dosing possible for batch processing. Laminar mass flow instruments can only be used when the process liquid is unchanging and its fluid properties are known.
Coriolis flow meters and controllers offer a solution to some of these limitations. Coriolis technology enables accurate measurement and control of mass flow even when the fluid composition of dosing mixtures is changing. More compact-type Coriolis devices are ideal for low-flows and also provide density readings. Additionally, dosing solutions with Coriolis can be made with CIP/SIP compatibility. And although they are often associated with a higher initial cost, long time cost of ownership for Coriolis instruments is reduced since no annual recalibration is typically required.
While some large scale food production processes require high flow rate Coriolis instruments, many dosing applications can benefit from the precise, low-flow measurement and control offered by the CODA-Series of Coriolis mass flow meters and controllers. With flow rates ranging between 0.08 g/h to 300 kg/h, CODA devices are available in several models customizable to the exact requirements of each application. Contact Alicat to learn more about how Coriolis can maximize your dosing process.