Moisture Control in Animal Feed Production
One of the big challenges in the animal feed industry is the number of different formulations that can be produced by a single plant. For each batch, it is essential to ensure that the quality of the product is correct so that the animals are fed a balanced nutritional diet optimised for their type and stage of development.
For this reason, moisture sensors are often used in conjunction with a control system that manages the formulation parameters. Controlling and measuring the moisture enables the correct calibration for each of the different formulations.
Moisture control is a key factor in ensuring the final feed is palatable, retains its nutrients, and is consistent.
Benefits of Moisture Control
- Improve nutritional consistency
- Reduce spoilage and waste
- Improve shelf life
- Optimise pellet durability
- Increase plant efficiency
- Reduce process downtime
Where to Measure Moisture
Effective moisture control of the entire process requires the installation of online moisture measurement sensors in several different positions.
In Figure 1, the green arrows show suggested sensor locations. The numbers within the arrows relate to each point below:
- Measurement between raw intake and storage silos allows unsuitable incoming materials to be managed.
- Ensures raw materials are correctly proportioned, compensating for varying moisture levels in stored material.
- Drying or Conditioning may be necessary in hot and/or wet climates to increase the moisture of materials for milling, as dry material increases breakage and dust.
- Measurement in the mixer allows the addition of water to ensure material is sent for conditioning and extrusion/pelleting.
- The measurement at the input of a dryer can be used as a process variable for feed-forward control.
- Measuring at the output of a dryer enables feedback control from the setpoint error.
- Measuring at output of cooler prior to packing/storage allows control of cooler parameters and a final quality control check prior to storage.

Recommended Installation
The Hydro-Mix XT sensor is installed in the mixer end wall to ensure the mix has the correct moisture, is mixed homogeneously, and is ready for the next process stage.


Industry Expert Opinion on Moisture Control
“…if we maintain the correct moisture on a real-time basis throughout the process, we see there is a positive impact on energy consumption as well inside the feed mill. We have seen, generally, there is a 10% reduction in the energy consumption of a pelletizer if a feed mill uses moisture optimization. The benefits are multi-faceted in my view.”
Dr Prince Nanda, Global Product Manager at Trouw Nutrition1
Conclusion
Animal feed comes in all shapes and sizes and has many different formulations. Moisture measurement is a vital element of the plant to ensure the efficiency of the process and provides precise process variables to the control system that can use stored calibration data for different formulations.
Moisture measurement is also important for a quality controller to ensure the feed is palatable, retains its nutritional value and has a suitable shelf life.
- Dr Prince Nanda (April 2019, updated March 2022). Moisture control in feed mills could result in real savings.
https://www.feednavigator.com/Article/2019/04/05/Moisture-control-in-feed-mills-could-result-in-real-savings/ ↩︎