Automated decoration with Hans Brunner moulds

The colourful decoration of chocolate products is currently very much in vogue. But how is the colour applied to the product? The company Hans Brunner knows how it works. As early in the process as the concept phase, the company works closely with customers and machine manufacturers, such as the Swiss company Knobel in order to be able to create a product that looks perfect.

Before the chocolate mould for producing the hollow figurines is spun or cold stamped, the empty mould halves are decorated with coloured chocolate. Precise dosing, clear demarcation and observance of minimal line thicknesses are the deciding factors when it comes to achieving a perfect coloured surface. This applies to relief articles such as tablets, pralines or lollies just as much as it does to hollow figurines. The area to be decorated is designed so that the chocolate can spread across it as well as possible and that defects such as air pockets are avoided. When determining which areas should be decorated, it is important to ensure that they are relatively smooth and not in close proximity to the walls of the cavity. It is also important to ensure that the chocolate cannot run out of the defined areas, and that the decorating nozzle cannot collide with the mould. Areas that should receive several different colours are determined right back in the design stage with the in-house designer, on the basis of a coloured sketch.
In many companies, the products are still painted or decorated by hand. But with decorating machines, this time-consuming work can be completely automated. The coloured mixture is dosed from the CAD moulding machine. Decorated areas can also be moulded with different colours on top of one another. It is important to ensure that the colour demarcations on the mould are set appropriately, and that the order in which the decorating nozzles apply the coloured chocolate is correctly configured. Therefore, for example, when colouring eyes on a product, the pupils are done first, then after a short cooling stage, the whites of the eyes are then poured over.

Completely new method of production

When using different moulds on one system, Brunner uses various logical mould recognition systems. The most common method is by using RFID technology. The decorating machine recognizes the code on the mould and loads the correct decorating programme.
The innovation of combining decoration with the cold stamping pro­cess opens up a completely new method of production. This procedure produces precisely defined chocolate shells for pralines, bars, tablets and also for hollow figurines. Compared with the spinning system, this process achieves a thinner, more even wall thickness. So, for hollow figures with precise wall thicknesses, e.g. surprise products, capsules can be reliably inserted into a defined hollow cavity. When using the cold stamping procedure, chocolate mixture can be saved, and process times are shorter. The product weight can be precisely calculated beforehand, exactly to the gramme. Brunner already does this during the product development phase.
For making the moulds, Brunner uses both the injection moulding and thermopress methods. Both methods have their advantages in different areas and can so be deployed according to the customer’s individual needs.  

interpack, Hall 1, Stand B 22