Foreign body control: Faster processes plus reliable separation

Before fruit bars reach the consumer, they should be subjected to a thorough foreign body inspection. Viba sweets has now replaced its X-ray inspection technology. An IX-EN X-ray inspection system from Ishida has been installed for more efficient and accurate detection. In addition to foreign bodies, the new machine also detects other quality defects such as breakage, deformation or double filling.

Viba sweets is primarily known as a manufacturer of nougat and chocolate specialities. As a low-fat alternative to these products, the Thuringian company developed fruit bars back in 1967 together with sports physicians and national coaches. Since then, the Dried fruit snack in convenience format as a practical companion for sports or when travelling.

Today, Viba sweets manufactures sweets on an impressive 40 metre long production line a wide variety of fruit bars from exotic fruity to coffee or cream. In total, more than 60 recipes are available in several packaging formats with filling weights of between eight and 50 grams produced. The high-performance line has a maximum output of more than 500 fruit bars per minute.

Before the final packaging, the snacks pass through an integrated production line. Foreign body inspection with X-ray inspection technology. This eliminates the IFS Food Standard „Higher Level“ certified manufacturers. As a natural product, the dry fruit mass between the wafers may contain impurities such as small stones or pieces of glass.

Replace problematic ejection

An X-ray inspection system used until recently could no longer fulfil the requirements of Viba sweets for various reasons. The process and project engineer Francisco Taberner explains: „Because the fruit bars are very light, their positions and distances on the conveyor belt were altered by contact with the curtains at the inlet of the X-ray inspection system. This jeopardised the safe ejection of contaminated products.“ There was also a need for more information to determine the type of foreign body and localise it in the product for the Root cause analysis.

„New recipes are stored in just a few minutes, and the easy accessibility speeds up cleaning measures,“ explains Francisco Taberner, Process and Project Engineer at Viba sweets.

Optimum solution for special products

Viba sweets therefore decided in favour of a Replacement of the X-ray inspection system. Before the investment was made, the machines of several suppliers were tested intensively with the company's own fruit bars, and in the end the decision was made in favour of the Model IX-EN from Ishida. Since its installation in August 2018, the system has been working at high speed in two- and three-shift operation.

Rejected packaging is reliably ejected without causing delays in operation. The delicate stainless steel curtains on the appliance's inspection chamber move so smoothly that the fruit bars are not affected by contact with them. Additional safety is provided by a Software for ejection counter-check, which stops the system immediately if packaging classified as contaminated is not detected by a sensor in the ejection container within a defined time window.

The IX-EN X-ray inspection system is very suitable for fruit bars because it was specially developed for inspecting light, thin and comparatively homogeneous products. To check for foreign bodies, the system measures the Density. The X-ray light is guided through the fruit bars and recorded by photodiodes. Depending on the level of X-rays received, a greyscale image is produced. If there are inclusions with a greater density than the product itself, these appear as dark spots on the image.

„The machine's touchscreen immediately provides information on the nature of the foreign bodies and where exactly they are hidden in the product,“ explains Francisco Taberner.

Increasing precision

The Ishida X-ray inspection system also fulfils the requirement for increased accuracy. „The software is significantly more powerful than the previous machine and also better than the other machines we have tried,“ reports Francisco Taberner.

The patented technology of the Ishida IX-EN X-ray inspection system is based on software with a learning genetic algorithm. By analysing image data over several generations, the device achieves a very high level of accuracy. As recurring contamination usually occurs in food production, a more precise protocol for the calibration can be created with each test procedure. For calibration, it is sufficient to x-ray a test object two to three times.

All detection requirements fulfilled

Viba sweets achieves very good results with the IX-EN X-ray inspection system. Detection rates for stone, glass, plastic and metal. Stones and pieces of glass, for example, are also used at high speed. from one millimetre reliably found. The system also uses a weight check function as an indicator for other quality defects that would previously have gone undetected. Deformed and broken fruit bars can be identified and accidentally double-filled packaging can be removed from circulation.

One Data logging collects all important information so that proof of flawless production processes can be provided later. The reports also help with root cause analysis and the elimination of recurring sources of error. Viba sweets monitors fulfilment of the detection specifications in each shift by carrying out several functional checks with prepared test specimens.

Time-saving X-ray inspection system

The employees at Viba sweets were quickly familiarised with the X-ray inspection system. According to Francisco Taberner, the machine is „very easy to operate“. After an automatic set-up, the system is up and running within 90 seconds ready for use, and fine adjustments can then be made during ongoing production. Up to 100 programmable presets allow product changes at the touch of a button. This is an important aspect given the variety of products. The new X-ray inspection system therefore saves a lot of time and enables more efficient processes at Viba sweets.

The confectionery manufacturer Viba sweets GmbH from Schmalkalden in Thuringia is the leader in the German nougat bar market with a market share of over 60 per cent. Founded in 1893, the traditional company has more than 30 different nougat products in its range. In addition, there are handmade pralines, marzipan, fine nut dragees, fruit snacks and chocolate items. In 2019, Viba sweets expanded its fruit snacks range to include three new flavours such as bars with a thin chocolate coating. The Viba Group has also owned the brand HEILEMANN with its high-quality products[/infotext].