Liquorice or starch gels begin with a pre-mixed slurry of wheat flour, sugar, glucose syrup, water and other minor ingredients, such as flavours or colours. This slurry is then pumped through a viscotator which is a steam jacketed heat exchanger that cooks the slurry. The cooked mass passes into the extruder, which has two functions; firstly to remove moisture via a vacuum system and secondly to develop pressure for the extrusion control system.
The extrusion control system is where the final product is really formed. On multicoloured lines, flavours and colours can be added before the shape of the product is formed by the extrusion dies. This is also the time that the liquorice or starch gel can be combined with sugar paste to form a co-extrusion. Sugar paste is the most common co-extrusion, but chocolate, pectin gels and fruit gels are other alternatives. The next stage is cooling the product, typically using a multi-tier tunnel. If the product is to be sugar dusted this is done before cutting by the automatic guillotine.
Manufacturers working with liquorice products face many technical challenges. According to Neil Brown, Technical sales at BCH Limited, based in Lancashire, UK, the past few years have seen many customers expressing a preference for softer texture liquorice, which has reduced the difference between liquorice and gelatine-based gummy products. “The addition of multiple colours, especially natural colours, has further blurred the differences,” he added. “At our company, we now refer to liquorice lines for traditional black products and starch gel extrusion lines for everything else.”
It is well known in the confectionery industry that the market for manufacturing equipment is becoming increasingly competitive given that many companies now offer similar high-quality systems. However, as Lee Fish, Technical Sales at BCH, points out, technology does not stop and is continually advancing, so it is very important for companies to have a programme in place for improving their machines. At BCH, the company uses an Innovation Centre to test out new ideas before they go into production. The centre, measuring 1022m2, features a complete extrusion line that can be used for trials and for developing new products.
As well as keeping up with new technology, it is also crucial for companies to differentiate themselves, such as by offering a whole process rather than just the engineering. “For instance, at BCH, we start by asking the customer which products and how much of each product they need,” said Guenter Lang, International Sales Manager at BCH. “Then, in our Innovation Centre, we develop recipes with our food technologist Jancie Ng to make samples to the right specification.”
It is important to produce a line that can be installed and used for production very quickly. “We have the advantage that we have already developed these recipes in our Innovation Centre,” added Guenter. “These recipes are tested before commissioning so that the line goes into production immediately.”
When it comes to choosing and investing new liquorice equipment, Lee says that there are a number of considerations that should be taken into account. “The first thoughts a customer should have is simply what products do they wish to make? And how much of each product do they need? A machine that makes sugar dusted single colour products is much simpler that a machine that makes multi coloured sugar filled products. A second consideration would be the size that they have available in their factory, even with a three tier tunnel a liquorice or starch gel line can be 40 metres long – or more!”