Flavouring Systems

Selecting the appropriate system:

Which base product needs to be flavoured?
The unit that is to handle the product during the coating process must match the product specifications. For most extruded products - which are of small to medium size and positioned randomly - Schaaf recommends the use of horizontal drums slightly inclined towards the exit end. Drums are also suitable for small products, which are potentially difficult to handle on conveyor systems, especially those with wire mesh belts. Schaaf flavouring-drums offer the following advantages:

  • The special profile of the drum ensures a gentle yet regular movement within the product mass, ensuring uniform distribution of the flavouring material while minimizing product damage.
  • The stainless steel construction and easy access to the inside of the drum allows for easy cleaning with warm water. This also helps to ensure a hygienic processing environment.
  • The variable drum speed allows for adjustment to a wide range of flavour application requirements for a variety of products in the same system.


How is the flavouring material prepared?
A homogenous and uniform flavouring consistency is very important for ensuring a good overall product quality. The flavouring material is usually prepared as a fluid medium, either as fat or water, depending on the product design. Unlike fat-based flavourings, water-based flavourings require at least one drying step after the flavour has been applied. Flavouring is prepared by mixing together the fluid medium and the flavouring materials according to the set recipe. In order to ensure a homogenous flavouring consistency, equipment for heating and vigorous mixing should be provided in the preparation unit. Another similar unit is required to hold and feed the flavouring for the product while a fresh batch is being prepared.


The various slurry preparation systems offered by Schaaf comprise 2 vessels, both of which are jacketed and electrically heated with thermo-oil. They are fitted with suitable stirring units. A special high-power pump is provided in the preparation tank that re-circulates the slurry during preparation and also transfers the slurry to the holding vessel at a later point.

Other advantages of slurry preparation systems include:

  • Temperature control of the flavouring using PID controllers receiving temperature feedback from the slurry mass.
  • Double walled, usually thermo-oil filled, indirect heating systems for gradual and uniform heating and prevention of hot spots.
  • High speed Turbo stirrer in preparation kettle for quick mixing of components.
  • Low speed stirrer in holding kettle to avoid component separation and salt sedimentation.
  • A high capacity transfer pump in the preparation kettle can be used for recirculation and also for transferring the flavouring quickly and completely into the holding kettle.
  • Full stainless steel construction of the systems ensures easy and proper cleaning, thus guaranteeing hygienic operation.
  • Special CIP designs available for slurry preparation systems.


Simple Solutions for Complex Finished Products


Besides liquid flavouring, it is also possible to apply dry flavouring materials to the product. The use of liquid flavourings exclusively or in combination with dry flavourings depends on the product design. Schaaf offers both kinds of flavouring options. The application of the flavouring materials - slurry and dry flavour - comprises 2 stages - dosing and application.

Dosing options:
To ensure accuracy, liquid slurries can be dosed using volumetric pumping systems, while dry flavours can be dosed with the help of screw dosing units. Schaaf offers:

  • Eccentric screw pumps (with variable speed drives) for high viscous masses without suspended solids.
  • Peristaltic pumps (with variable speed drives) for low viscous masses, with special inserts capable of withstanding high slurry pressure.
  • Accurate double screw dosing systems (with variable speed) for dry flavours.


How are flavouring materials applied to the product?

The application of the flavouring material should be uniform and constant during production. Schaaf uses compressed air-based special spraying nozzles to finely distribute the liquid flavouring mass onto the maximum possible product surface, and an empirically tested flavour transport and dispersal system to apply the dry flavouring materials. Optional pressure-triggered automatic nozzle cleaning systems can be activated for online clearance of most nozzle blockages without any operator involvement.

M/c no. Unit Name Application for Nominal Capacity Remarks
319 Coating drum-800 Continuous flavouring 200-250 kg/h Low product volume
320 Coating drum-1200 Continuous flavouring 400-500 kg/h High product volume
318 Coating drum-1600 Continuous flavouring 600-750 kg/h Very high product volume
334 Dosing/Spraying sys. SN Low viscous slurry max. 150 kg/h Dos/Spray for fat coated snacks
335 Dosing/Spraying sys. SNC High viscous slurry max. 150 kg/h Dos/Spray for sweet cereals
357 Spraying unit for snacks Fat based slurries max. 60 kg/h Spraying for fat based slurries
356 Spraying unit for cereals waterbased slurries max. 60 kg/h Spray for water based slurries