Process technologies for tomorrow.


Many food products require heat treatment to make them suitable for human consumption. Steam is a well accepted medium to be used, because of its properties. Steam kills pathogenic bacteria easily, has good thermal properties, is inert (no oxygen) and clean. If steam is superheated, it becomes a gas and can be used for drying purposes as well. Hosokawa Micron offers process equipment for the steam sterilization of food products.

HSSP batch sterilization process

Nauta vacuum dryer Nauta vacuum dryer

HSSP is a flexible batch sterilization process based on the Nauta® conical dryer design. It is especially suitable for the heat treatment of products like herbs, spices and teas.

The working principle of HSSP involves six steps before a product is sterilized. Raw material in big bags or sacs is unloaded manually in the Nauta sterilizer (step 1). All next steps of the HSSP process are fully automated. A recipe is selected on the control cabinet and soon after the treatment process is started. The sterilizer is put under vacuum, heat is added to the product via the wall of the sterilizer and the mixture is homogenized. Steam is injected for a very short moment to minimize the quality losses.

Next step is the post-drying step, in which the condensed water is evaporated at vacuum conditions. A cooling water condenser is trapping the evaporated water vapours and ethereal oil losses. The moisture level of the sterilized product sets the duration of the post drying step. In step 5, the product is cooled under atmospheric conditions. During this phase it is possible to reintroduce some oils to the product. The product is ready for discharge from the Nauta sterilizer. During discharge any lumps in powdery products are removed before bagging or loading in a container.

Automated process

HSSP is a completely automated process in which each product has its own specific heat treatment. Cleaning in between batches is not necessary as the amount left in the sterilizer is minimal. It is easy to integrate with a batch traceability system such as SCADA.


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

Our test and process development centre in the Netherlands offers unique possibilities for testing your product to determine the most efficient process, system or plant prior to final design. We can provide laboratory-level as well as production-sized trials.

Whether you wish to test a single machine or a complete powder processing system, the same skilled and experienced staff are here to help ensure that your requirements are met, and that you are entirely satisfied with the results.

We offer process equipment and technologies from individual units to large scale bespoke system solutions. Our principle is to deliver high performance yet affordable solutions that meet our customers' demands and long term challenges.


To learn more about our powder process equipment and systems for steam sterilization of food products, 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 7% of companies rated by EcoVadis in the special machinery industry.

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