Tobias Zehnder, Technologist at FRITSCH World of Bakery, explains how MULTITWIST can deliver perfectly twisted baked goods at scale
Since the late 1990s, FRITSCH has been at the forefront of automating one of the most intricate and time-consuming processes in bakery production – the twisting of pretzels. What began as a response to a German baker’s vision to automate pretzel shaping has evolved into decades of innovation, culminating in the MULTITWIST system. In this interview, Tobias Zehnder, Technologist at FRITSCH World of Bakery, explains the origins of the first automatic pretzel twister, the challenges overcome along the way, and how FRITSCH’s technology continues to blend traditional craftsmanship with industrial-scale precision for the delivery of perfectly twisted baked products.
Could you start by telling us what inspired the development of the first automatic pretzel twisting machine?
Forming twisted products is one of the most demanding and, at the same time, labor-intensive and time-intensive manufacturing processes in the production of any baked goods. The driving force behind the development of an automatic twisting system in the late 1990s was a well-known German pretzel manufacturer who suggested automating this process. The first fully automated pretzel twister went into serial production for the first time in 1998, used commercially by the first customer the very next year, and presented at iba in 2000. This was an essential milestone which allowed the automatic production of pretzels for the first time.
The first twister, named “ASB,” was designed so that the ends of the pretzel dough strands were picked up from below and folded over. The first system sold produced 12,000 pretzels per hour and consisted of eight pretzel twisters.
What were some of the main challenges the team faced during the development process, and how were these overcome?
The complex design of the first pretzel twister required a lot of space, which was often unavailable in small bakeries. That’s why FRITSCH developed a pneumatic twisting system (PSB) in the second generation, which brought significant simplifications and improvements. A head machine for dough portioning was placed upstream of the PSB. The dough pieces ran along a conveyor belt, and a strand machine alternately supplied two PSBs with dough strands.
The key difference from the ASB was that the PSB used two grippers that grabbed the product from above and twisted it. This allowed production on continuous, sequential transport systems. The PSB also introduced new technical developments, such as stretching the strands while twisting the pretzel under tension to tighten the knot.
Another challenge was to produce as many different products as possible from a single dough strand. Therefore, the next step was the development of the servo-driven pretzel twisting system (SSB). Thanks to its tool change mechanism, it allowed the use of various customer-specific tools. With this system, it was possible to produce not only pretzels of different sizes but also rings and sticks.
With the development of the SSB featuring servo lift – which is still in use today – reliability, precision, and the range of usable tools were significantly improved. The small servo motors allow the gripping arms to be positioned with millimeter accuracy. This is essential for producing single-strand braids and other twisted baked goods.
In what ways does the MULTIWIST replicate or enhance the traditional pretzel-twisting method?
Products that look hand-twisted – that’s the quality benchmark of the MULTITWIST. The current generation of the MULTITWIST (SSB) achieves a performance of 2,000 pretzels per hour. In this setup, each twister is supplied by its own strand machine.
For industrial pretzel production, multiple twisting sections can be connected in parallel to form a “battery.” Modern large-scale systems can reach outputs of up to 20,000 pieces per hour.
The system is known for its versatility. What kinds of twisted products can it produce beyond pretzels?
The pretzels can vary in size, shape, weight and the placement of the twisted ‘arms’. A pretzel is never just a pretzel. There are also regional differences to consider; for example, whether a pretzel has a thicker section, a ‘belly’, or not. We also see a higher demand for pretzels made of sweeter doughs, such as brioche.” The FRITSCH system can even customise the positioning of the pretzel’s ‘arms
With a growing trend for greater variety in terms of shapes and sizes, in addition to the classic pretzels, customised twisting tools are designed, depending on the intended product ranges. Solutions for rings, single-strand braids, knots, and pretzel buns – these are only some of the frequently-asked custom solutions for the FRITSCH twisting machine.
The heart of the MULTITWIST is the twisting unit. Using two gripping arms, the machine not only twists pretzels in various shapes and sizes – it also handles sticks, rings, and labour-intensive products like single-strand braids and knots with ease.
Read the full interview in our latest issue here
