Crystallisation at an ideal temperature gives melt-in-your-mouth sensation:

Special chocolate pump enables tempering across whole conveying area

Look behind the scenes

Statistics tell us that every German citizen eats around 9.5 kg of chocolate a year, in the form of bars, hollow figures, pralines and such like. The sweet may be very popular, but it is extremely complicated to make. In particular, the temperature has to be precisely controlled at all times to achieve the later melt-in-your-mouth effect. To avoid there being any gap in the processing chain here, NETZSCH Pumpen & Systeme GmbH has developed a special tempering positive displacement pump and also a rotary lobe pump with similar features.

Challenge accepted

The secret of high-quality chocolate is ensuring that the fat crystals contained are configured in the best possible way. This is directly dependent on tempering. If the temperature is too high or too low, chocolate will no longer melt in your mouth or will not have an attractive, shiny finish, but a milky, lacklustre look instead. The viscosity also changes along with the crystal content, and this may lead to problems further on in processing or when filling. Tempering is therefore crucial in terms of quality: Good chocolate needs smooth conveyance at a constant temperature.

 Excellently solved

To ensure a constant temperature an adjustable heating jacket has been added to the NEMO® progressing cavity pump for tempering. It allows the required heat to be kept constant through the various stages of the process. In order to meet the high hygiene requirements in the food industry the materials used, especially the elastomers, are approved by the FDA and the pumps meet the requirements of the Federal Institute for Risk Assessment (BfR), along with those of the Russian GOST-R.

The TORNADO® rotary lobe pump was equipped with appropriate features to fulfil the same requirements for product protection, residue-free conveying and hygiene. All components used in the T.Sano® rotary lobe pump that come into contact with the medium are made of stainless steel to comply with food safety guidelines. A unique feature that sets the pump apart from every competitor is its lubricant oil free design which eliminates any risk of contamination.


Chocolate is one of the most popular sweets all over the world. However, its production is extremely demanding, with correct tempering being particularly crucial as far as product quality is concerned

NETZSCH chocolate pump

In order to be able to maintain the required temperature at every stage, the NETZSCH chocolate pump is fitted with a complete heating jacket which can also be controlled segment by segment if need be.


Hygiene was the top priority in designing the pump. The coupling rod was therefore incorporated using flushed open pin joints which inhibit product adhesion.

T.Sano rotary lobe pump

The T.Sano rotary lobe pump is not only EHEDG certified, it is also certified by the American 3-A-Certificate.