International FoodTec Award 2024 Gold: Trajectory Mixer Replaces Agitator
The trajectory mixers from hs-tumbler take a completely new approach, as they completely dispense with stirring and kneading instruments. Instead, a high-speed curved path is created for the process container with the contents to be mixed. This convinced the expert jury of the International FoodTec Awards 2024, which honoured the process with a gold medal. We wanted to find out what's behind the "stirring revolution" from Quakenbrück, Germany and spoke to the two managing directors Bernhard Hukelmann and Peter Stellbrink.
Mr Hukelmann, how did the development of the gold medal-winning agitatorless mixing system come about?
Hukelmann: Firstly, thank you for the opportunity to report on our global innovation in the Anuga FoodTec Magazine. Trajectory mixing was developed several years before the company was founded. The starting point was corresponding research at the German Institute of Food Technologies in Quakenbrück ...
You were head of the automation technology division there for many years ...
Hukelmann: ... and I worked on the process part-time during this time. Thanks to an investor, Peter Stellbrink and I were able to found hs-tumbler GmbH two years ago. We found the perfect premises for launching our company in the BIQ Business and Innovation Park in the immediate vicinity of the DIL.
The initial idea grew into a market-ready machine that makes meat more tender and ensures better absorption of marinades ...
Hukelmann: Our intention was to replace the lengthy tumbling process with an almost continuous process, thereby increasing flexibility and quality. In the end, it was "only" necessary to introduce shearing forces into the meat. As with conventional tumbling, this causes protein breakdown, an increase in tenderness, a widening of the spaces between the fibres and consequently the absorption of marinades.
Peter Stellbrink: In this respect, the hs-tumbler is not a tumbler in the true sense of the word, but rather a system that carries out the tumbling process in an optimised manner. The servo-controlled cam track - the trajectory - of the process container is the equivalent of a mixing tool and is freely programmable.
The K1 "Handwerk" (Handicraft) is an agitator-free mixing and kneading system with a single container. The system is used for processing food in butcher shops and bakeries as well as in commercial kitchens and canteens. © hs-tumbler GmbH
What is the requirement profile of a modern mixer for food processing? And what are the advantages of the trajectory process?
Stellbrink: There are many system manufacturers who have been on the market for decades with tried-and-tested solutions. The challenge for their mixers is the variety of products demanded by consumers. Nutritional trends, intolerances or allergies must be taken into account on demand. This is hardly possible with today's mixing systems, which rotate on their own axis or have a motorised stirrer.
Hukelmann: This is where the hs-tumbler comes into play, as its process container doesn't rotate. Instead, it travels on a programmable curved track. The highlight of this "stirring revolution": The product in the container gently processes itself. The shearing forces process not only a small part of the process volume - as with the previous systems - but the entire contents. This reduces processes that would otherwise take several hours to, for example, 20 seconds. Of course, the batch is smaller, but the total output is extremely high due to the high production frequency. With a batch size of 60 kilograms, we use a J4 line to continuously produce over seven tonnes of cooked ham per hour.
That's a multiple of the tumblers currently available on the market ...
Stellbrink: In addition, the containers are easy to clean, require no additional cooling and no vacuum. The footprint for the system is also quite small at two by two metres. But the list of advantages is even longer....
Did resource conservation and energy efficiency play a role in the development?
Hukelmann: Yes, both aspects were a driving force behind the idea. The hs-tumbler makes it possible to switch from a batch process to a much shorter flow process in which production starts without any run-up time. The energy savings associated with this often amount to more than 50 percent.
Stellbrink: And the principle can be taken to the meat counter with one of our compact K1 systems, for example for marinated grilled meat. Customers can put together their own personalised meal from the counter and take it home with them straight away. With a footprint of 80 by 80 centimetres, the K1 is available with four, five or seven-litre containers.
Can you name a customer that uses this kind of on-demand concept?
Stellbrink: The K1 is designed for commercial kitchens and can produce an incredible range of foods, from vinaigrette and coleslaw to pizza dough. We're delighted with the cooperation with the caterer "Berlin Cuisine", which uses the system.
Hukelmann: The top chefs of "Berlin Cuisine" create a wealth of their own recipes on the K1. They can serve beef with "four times the flavour", as they say, and an abundance of freshly prepared dishes. These include vegan products that were previously purchased as finished products. This is of course appreciated by the customers of the catering company.
How versatile is the system?
Hukelmann: Each product class with its own viscosity range has so far required an agitator matched to it. To illustrate this point: Nobody would think of kneading pasta dough with a whisk. Our hs-tumblers are different. They can process products across the entire viscosity range, from cream and meat preparations to pasta dough - and everything in between. Because the path curve can be specified, the process container follows the viscosity of the product to a certain extent during operation.
Viscosity is an important keyword here. Are there any limitations with regard to rheological parameters?
Hukelmann: That's a good question. The uniqueness of the system can be emphasised once again here. With the hs-tumbler, substances can be processed over a wide viscosity range, from below one millipascal second to around ten to the power of six millipascal seconds. Although this is a very gentle process, as the product only processes itself, it is capable of introducing massive amounts of energy.
Stellbrink: In addition, almost all homogeneous, heterogeneous and colloidal substance mixtures can be processed. Many prospective customers don't trust the system to do this at first because the process looks like shaking from the outside.
Does this mean that dry powders for baking mixes or beverage preparations can also be processed in order to package them ready for filling?
Hukelmann: Actually, yes. The trick is that we can determine at the end of the path curve how "sharply" it is run. This enables the degree of shearing forces introduced to be determined. The result is intensive mixing of all components.
Heating and subsequent cooling are typical requirements in many mixing processes. Can this kind of heat transfer be realised with trajectory mixers?
Hukelmann: The product in the process container is subjected to specific centrifugal forces. As a result, the contact between the process product and the container wall is excellent. So we don't have to wait for convection. In addition, there's usually a turbulent flow on the surface, which promotes heat transport in both directions. We can bring the food to a homogeneous temperature level in a short time - faster than in a microwave.
You've already mentioned it: With the J4, you offer a variant for industrial use. What characterises the machine and how can it be integrated into the processes on site?
Stellbrink: With the J4, we utilise the principle of counter-rotating accelerations through the four symmetrically arranged process containers and work extremely energy-efficiently, as the vibrations of the individual containers cancel each other out. Our industrial systems find their way into production via optimally equipped system integrators. In the food industry, the first commissioning should be completed by the end of 2024 at the latest. We see integration in the non-food industry as early as mid-2024.
Hukelmann: For customers, the J4's enormous performance is not even the decisive factor. Our driving forces are flexibility, quality, ease of cleaning and a high degree of automation. An additional advantage is its usability for highly viscous and vegan products. This makes the hs-tumbler a secure investment for the future that is ideally equipped for coming requirements.
What are the biggest challenges for you as a system manufacturer?
Hukelmann: The main challenge is that, on the surface, our process looks like shaking. Food manufacturers often underestimate the potential and conclude from their experience with traditional mixers that the hs-tumbler is not suitable for their applications. Our product requires a great deal of explanation and demonstration. But I always enjoy it when customers are initially sceptical when they come to us in Quakenbrück and we see their eyes light up after successful tests.
Food Tec Award
With this in mind: How important is the Anuga FoodTec Award for you?
Hukelmann: The award is recognised as a prestigious prize for technological innovations in food processing and is very important for our start-up, as is Anuga FoodTec as a trade fair platform. Thanks to the gold medal, we can hope for a good response, gain further recognition and expand our customer base.
Two who want in on the action: Bernhard Hukelmann (left) and Peter Stellbrink see great potential for their trajectory system, which was honoured with the International FoodTec Award. © hs-tumbler GmbH