Dosing of sugar icing on bakery products

Company: ViscoTec

Equipment Snapshot: Sugar icing is the "icing on the cake" of many baked goods. The dosing is usually done by hand in complex production steps. Most today's gingerbread decorations, for example, are still made manually with the piping bag. But the degree of automation is also being increased in the baked goods industry. There are several reasons for this: Stricter hygienic regulations or high personnel costs, for example.

With the endless piston technology on which the dispensers and dosing pumps from ViscoTec are based, decoration tasks or filling in the confectionery industry can be carried out semi-automatically and fully automated.

Automation in the confectionery industry or in the production of baked goods cannot be compared with automation options in other industries such as the automotive industry. Instead of a standardized component with defined manufacturing tolerances, the "living product" is worked on here. As no two baked goods blanks are the same, this type of application requires advanced camera technology. In order to then be able to react in real time to deviations in the moulded part, flexibly adjustable dosing technology is required. With ViscoTec dosing technology, the necessary parameters such as discharge quantity, speed etc. can be adjusted at any time and analogously during the dosing process.

The progressive cavity pump offers excellent possibilities especially for highly viscous or difficult foods such as icing sugar. Thanks to its simple handling, the dosing pump can be used in automation solutions and integrated into all common robot systems.

A typical application is the fully automated decoration of biscuits, pastries and small cakes with sugar icing. A ViscoTec VHD dispenser has been integrated into a VARO plant, a machine and plant manufacturer for production plants in the pharmaceutical, food and non-food sectors in Denmark. The food robot automatically decorates various bakery products. The result is an efficient, continuous and flexible pastry decoration.

Varo had two special requirements:

Capturing the cake using a camera system: Most cakes differ in shape, although they are the same type of cake. Varo uses several functions of a modern Cognex camera system.
Decoration control: Varo uses a ViscoTec Hygienic Dispenser to control the flow very precisely.

The robot can dose different patterns, even freehand drawings. Specially developed robot software converts the sketches into robot paths. In conjunction with a camera system, the dosing system automatically recognizes which piece is next in line and which pattern is to be executed on it. The VARO system can apply different decorative patterns—both hot and cold—in the same process. It convinces with its absolute ease of operation. And it is compatible with all types of pumpable decorations such as glazes or chocolate and fruit sauces.

Regardless of the actual dosage, the product feed of the sometimes highly viscous masses is still a challenge in advance. Working with an ordinary pressure vessel as product supply can lead to air pockets in the material to be dosed due to uneven filling and thus to interruptions in the dosing flow. This in turn has undesirable effects on the overall result of the decoration. ViscoTec drum emptying systems ensure uninterrupted and constant product removal - and thus seamless production. The product feed of the highly viscous sugar icing is therefore also carried out in the application example by drum emptying systems, which are also based on a progressive cavity pump. Together with a follower plate, this pump empties the barrel almost residue-free in a very gentle process. Emptying is therefore mainly achieved by the suction effect of the progressive cavity pump and not by applying high pressures to the follower plate and the resulting shear and pressure stress on the sugar icing (as is the case with piston pumps, for example). Due to the gentle conveying, the sugar icing can be fed to the dosing pump without changing its properties. Subsequently, the sugar icing is dosed onto the biscuits and can be applied to the biscuits in any form, with any pattern or writing in combination with the robotics and software. There are no limits to creative design and imagination here: For example, seasonal decorations such as Christmas patterns on gingerbread or even motifs for Easter, as well as classic cake decorations can be realized with completely new motifs and even with the most difficult fonts or lines. This automated decoration offers large bakeries and confectionery manufacturers completely new possibilities and opportunities to automate their production and design it with process reliability in order to guarantee uniform quality and product standards. A considerable savings potential for today's often still very labour-intensive activities.

"A key to success is knowledge about the icing and the control of it. When using a ViscoTec pump we do not only get the precise control of the flow but also a system that is durable and easy to clean. Our direct collaboration with ViscoTec ensures the best solution for any case," says Arne Lundfold Bjerring, head of engineering at Varo.

Another possibility in which progressive cavity pumps are used in a completely new environment is filling applications in the confectionery sector: Where simple piston metering systems are still reaching their limits (e.g. due to too high viscosity), the applications are implemented either at extreme technical, and thus also cost-intensive expense. Here, the progressive cavity pump can be used as a dosing or filling pump. Difficult and highly viscous media, such as honey mixtures, can be dosed and filled without problems. In addition, confectionery manufacturers have the advantage that completely new products and blends can be developed and finally produced, because in the past the technical possibilities were simply lacking.

The highly viscous liquids, such as pastes or creams, are dosed extremely gently and their structure is not changed. Here too, chunky mixtures, e.g. fruit pieces or small biscuit pieces, can be pumped effortlessly. Depending on the application, the dosing pumps can be mounted directly on a fully automated filling station or, for example, in a stationary or semi-automatic system.

Decoration as well as filling applications are comparatively new areas of application for progressive cavity pumps in the food industry, enabling users to automate and completely restructure processes.