Process technologies for tomorrow.


Food processing companies are becoming increasingly aware that products they currently regard as 'waste' from their production process can be upgraded to high-quality products rather than being disposed of or used for low-value applications. The process to recover valuable nutrients such as animal-based proteins from such side streams often involves drying. Hosokawa's DMR flash drying system can be a feasible and more economical alternative to spray drying thanks to its energy-saving design. This enables you to maximize both the cost benefits and the sustainability benefits when valorizing your residual streams.

Fish/seafood side streams (head, bones, skins & guts)

Many residual products from the processing of meat, fish, vegetables or fruit, as well as side streams from bakeries, breweries and biorefining plants, can contain proteins or have other functional properties which are interesting from a nutritional point of view. The processing of fish and seafood such as shrimps is a good example of an industry that produces 'waste' (e.g. heads, bones, skins, guts) which can be valorized and converted into high-quality and nutritious animal-based protein for use in the Food & Feed industry.

Valorization of residual streams - Whey protein powder

A typical system to valorize residual streams:

Grinder > Cooker > Screw press > Decanter > DMR flash mill dryer

  • Grinder: The grinder is used to reduce the size of the residual products, e.g. by crushing fish bones.
  • Cooker: Heat is applied for better shifting and to prevent bacteriological problems further on in the process.
  • Screw press: Most of the free fluid (water & fat) is pressed out.
  • Decanter (3-phase): Liquid phase is separated into 3 streams: water-phase, oil-phase and wet press cake (pulp).
  • Evaporator (if necessary): This can be used to increase the dry matter content in the water-phase and achieve evaporated stick water.
  • DMR flash mill dryer: The wet press cake (mixed with evaporated stick water if necessary) is flash dried to obtain a high-value, nutritious powder.

Step-by-step process

In the case of fish bones, the grinder is used to reduce the size and prepare the products for further processing. The resulting material is then cooked and strained, and the liquid phase is decanted into the water phase, the oil phase and the wet press cake or 'pulp'. The oil phase can be further processed and purified for into fish oil, which can be used as a flavouring ingredient. The water phase (stick water) can be thickened in an evaporator and mixed with the pulp as feed material for the dryer system in order to produce protein powder.

Efficient drying of temperature-sensitive products

DMR flash mill dryer DMR flash mill dryer

The right drying system plays a key role in converting the goodness inside the residual material into a profitable powder product. Hosokawa Micron's unique flash drying technology leaves the temperature-sensitive components such as aromas, flavours and proteins intact and prevents oxidation. Thanks to its unique design, the DMR flash mill dryer enables the precise adjustment of a wide range of parameters – including the RPM of the mill disc, the classifier, the suction fan, the feed rate and the inlet and outlet temperature – to carefully manage the exposure time inside the drying chamber. This maintains the optimal product temperature as the particles pass upwards from the mill disc at the bottom to the rotating classifying wheel at the top of the chamber.

The DMR is also available with various mill discs and liners to adjust the particle size and amount of shear. The Hosokawa Micron R&D team will help you to identify the right parameters for your specific application. Besides ensuring that the residual streams retain their beneficial properties, this all-in-one process step can give you an important edge in terms of efficiency, return on investment (ROI) and sustainability. The result is a high-quality fish powder with a high protein content for use in fish-flavoured end-products such as fish burgers and shrimp croquettes.

Closing the loop by valorizing residual streams

The process to valorize organic waste streams from fish and seafood is extremely efficient and sustainable because it leaves no waste material behind. The inputs are converted into high-value fish oil and high-value fish powder, with the remaining water simply being evaporated into the air. Moreover, Hosokawa's DMR flash drying system is not only a feasible alternative to spray drying, but is also more economical. It has been specially designed to reduce energy consumption while also maximizing throughput speeds and minimizing downtime due to maintenance and cleaning. As a result, Hosokawa Micron's DMR flash drying technology supports the shift to more sustainable production methods, in addition to helping you tap into opportunities for producing high-quality and commercially interesting added-value products from your residual streams.

Need help setting up your process?

Test Centre in Doetinchem, the Netherlands Test Centre in Doetinchem, the Netherlands

Hosokawa Micron's experts in powder processing, drying and milling technology, can provide suggestions and advice to help you take full advantage of the opportunities in the valorization of residual streams.

Our development and engineering team is always on hand to help you explore new and innovative processes and applications. Testing is the foundation for a successful product or process. Our test facilities in the Netherlands offer outstanding opportunities to test ingredients, machinery, parameters and process flows, whether in the laboratory, as a pilot set-up or on an industrial scale, to ensure you achieve the necessary product quality and operating efficiency to generate the maximum return on investment for your business.

We also have rental equipment available for batch drying.

Common challenges associated with valorizing residual streams

If you're interested to discuss your interest in or production challenges in terms of valorizing residual streams, please feel free to contact us at Hosokawa Micron. We can help you on a range of questions about this value-adding activity, including:

  • How to achieve the highest quality powders, for better flavour intensity and nutritional values;
  • The best drying and milling techniques for residual streams;
  • The advantages of the unique DMR flash drying technology over traditional drying and milling methods;
  • How to plan, test and improve your protein powder processing system.


To learn more about our powder process equipment and systems for valorizing residual streams, contact us:



Hosokawa Micron B.V. is certified according to ISO 14001. Our certification covers all environmental themes of ISO 14001: air, soil, energy, waste, water, noise and hazardous substances. In addition, Hosawa Micron was awarded an EcoVadis Silver Medal for its sustainability achievements. EcoVadis determined that the company was among the top 15% of companies rated by EcoVadis in the special machinery industry.

Learn more