Authors : Olafur H Jonsson & Hennie Pieterse
Everyone involved in Food & Feed Processing knows and understands the importance of processing at the correct moisture content. Moisture impacts processing in at least the following ways :
In some processing steps, moisture at a certain level is required just to make that specific processing step works (for example, getting feedstock through a specific die size during Pellet Pressing).
Moisture is vital in the Food-Chemical changes that take place and interaction between ingredients during processing, and therefore has a determining effect on Quality and Nutritional Value of the final product.
Feed and Food Products are sold by weight. Producing food and feed products with moisture content too high may negatively effect quality and nutrition and even lead to Mould Growth and other moisture related problems. At the same time, selling food and feed products at moisture content lower than what is necessary means the Processor looses income as a result of unnecessary weight loss.
I asked my Industry Colleague at Intelscan, Olafur Jonsson, to explain the technical importance of Moisture Control in Food & Feed Processing in a bit more detail. This is what Olafur had to say:
Optimizing moisture content in feed and food processing is very important, especially from an economic point of view. Two factors make this optimization process even more important:
- Raw Materials (water included) have to be used efficiently during processing in order to minimize the cost of ingredients while maximizing income from sales of the final product.
- Energy prices continue to rise. This means the operational conditions of all equipment in the process need to be optimized to keep Drying Cost (if applicable) and other Operational Costs at a minimum.
Pellet Pressing is a good example. Correct Moisture Content of feed before pellet pressing will reduce the energy usage of the press. However, the added bonus of energy savings is that quality of pellets in terms of hardness and durability has been found to be improved when pressed at the correct moisture level. If the moisture content before the Pellet Press is too low, the following could result:
- Nutrients are lost as a result of the increased temperature in the Pellet Press.
- Moisture Content (and hence final product weight) is reduced as a result of elevated temperatures inside the Pellet Press.
It is therefore important to compensate for moisture loss during Grinding, Cooling and other processing steps in order to maximise output in terms of
- Utilization Efficiency of Raw Materials
- Energy Savings
- Better Physical and Nutritional Quality of final product
An Innovative Solution
New Technology makes it easier for the Food or Feed Processor to control moisture during processing. It involves an Online Moisture Sensor that “scans” the moisture content of feedstock instantly and continuously as it flows past the point of measurement.
The solution provided by Intelscan is based on Microwave Technology. The advantage of Microwave Technology compared to the NIR (Near Infrared) system is that microwave technology is not affected by other constituents such as Fat or Protein. This means that many different foods or feeds with various recipes or formulations could be measured and controlled without complicated calibration work.
The Intelscan Online Moisture Sensor monitors moisture, temperature and in some cases density on a continuous basis. These signals are interpreted by Tovalia Software installed on a computer in process control room of the feed mill or food processing plant. The interpreted values are then used to control one or multiple Moisture Dosing System(s). The Moisture Dosing Systems introduce water back into the process at a point where it is of
– Nutritional and
The Target Moisture Content at any point during the Process is set and controlled by the Feedmill Operator(s).
Moisture Sensing and Control Systems are designed with specific process requirements in mind.