Identification solutions for reliable data acquisition

As well as being used in the food industry to trace foodstuffs reliably, RFID technology, laser-based barcode scanners and image-based code readers can also be used to optimise production and packaging processes. Flexibility is a must in the food industry as one form of technology may be more suitable than others for certain processes. This is facilitated by uniform connectivity, an identical user interface and a uniform accessory concept.

Laser-based barcode scanning

Identifying products by barcode

The barcode is the oldest of the product identification data carriers, and it has been widely used in industry and trade since the 1970s. Nearly every consumer good is labelled with the EAN-13 barcode, which is valid all over the world and which encodes the GTIN (Global Trade Item Number), a globally standardised part number.

Thanks to barcodes, food is now labelled uniquely, reduced process errors have led to a higher degree of safety, warehousing can be automated, it is easier to move goods and, most importantly, products can be read incredibly quickly using laser scanners. If a product is recalled, the automated identification of the products involved and their distribution channels makes it possible to speed up all of the necessary measures. Giving each product a unique mark also has an impact on production, as the items have to be marked, read, verified and saved in the production line.

The Australian distribution centre of a large food company takes in 10,000 pallets each day, each of which is about 2 m high and loaded with different products, which are all provided with their own barcode. If a product is labelled incorrectly, this could mean that the wrong item is delivered and could make it extremely difficult to trace. Similarly, food that is not labelled correctly can trigger foodborne illness. An error rate of 2% would mean that 73,000 pallets would have to be taken apart, manually processed and inspected each year.

Checking codes on cheese labels at Arla Foods

In the Arla dairy in the Swedish town of Götene, up to 3000 cheese packets are weighed and labelled correctly every hour. No cheese can be made available on the market without a complete and clearly readable label. The print-and-apply machine manufacturer Autolabel AB developed a labelling system for Arla which works with photoelectric sensors, 2D vision sensors and barcode scanners from SICK. The CLV622 barcode scanner checks whether the label is in the right place and whether it is readable. Cheese packets with non-compliant barcodes are rejected automatically.

Waterproof reading performance

In the wet areas of dairies, slaughterhouses, meat-cutting plants, filling lines or food-processing facilities, barcode scanners must deliver impressive reading performance, even under the harshest of conditions. As the systems are cleaned frequently and intensively, the machines and their components are constantly exposed to water jets and aggressive cleaning agents.

The stainless steel housing of SICK’s CLV62x to CLV64x barcode scanners provide chemical material and corrosion resistance, ensuring reliable code reading, even in harsh conditions. Maier Packaging GmbH from Germany has developed a component for identifying barcodes on aluminium yoghurt pot lids. This component was designed to be used in the packaging system of the European market leader for dairy products. The company chose to integrate a SICK CLV scanner solution for wet areas as the pots and lids are cleaned in PSDI mode before the yoghurt is added and the lid is affixed. Once the lid has been affixed, the barcodes are read while the machine is at a standstill. The scanners are protected by IP69K housings with a plastic disc that can be cleaned using high-pressure cleaners and are resistant to acids and cleaning agents. The CLV6xx barcode scanner can also cope with the cold, and is suitable for use in freezers down to -35°C.

Image-based code reading

Identification in the second dimension

Alongside the traditional barcode, the food industry also uses 2D codes to ensure traceability and process reliability. While barcodes only code data in a single dimension, 2D codes map data in symbols, in a two-dimensional area that provides higher information density.

The data from a 2D code can be read using image-based code readers and processed further electronically. In the food industry, the use of data matrix codes is most common in intralogistical and packaging processes. QR (quick response) codes, are used on food packaging for mobile tagging so that consumers can trace a product with ease.

In the European Union, foodstuffs must be marked with a best-before date. In Germany, the Batch Marking Regulation also applies, requiring all foodstuffs to be provided with a batch number assigning the product to a production run. Both the best-before date and the batch number are marked on the product in plain text. Image-based code readers read barcodes, 2D codes and plain text automatically, shorten the processing times and therefore increase productivity.

Flexible, compact and well connected

The Lector62x image-based code reader from SICK is highly flexible. Using various image processing algorithms, it reliably identifies all types of codes used in the food industry, including barcodes (1D), Data Matrix and QR codes (2D), as well as plain text. The Lector620 High Speed variant reads codes at speeds of up to 6 m/s. Live images make it possible to analyse the code quality and reading performance, and images can also be saved for data archiving purposes.

Tracing fish specialties with mobile tagging

German frozen fish processor Femeg uses QR codes on its frozen-food packaging to provide the retail customer with extensive information about the origin and catching conditions of the fish via a smartphone app. In order to ensure that the QR code is also readable on the manufacturer’s fish packaging, the Lector620 Professional image-based code reader from SICK checks it during the packing process.

Traceability and intralogistical process reliability at Goedegebuur

In the packaging line of the meat processor Goedegebuur, based in the Dutch city of Rotterdam, code readers from SICK identify small 2D codes measuring 18 x 18 mm. As part of the intralogistical reorganisation of the packaging line, these codes were added to the labels in addition to the previous barcodes. Despite being mounted at a tricky angle, the Lector620 ECO still produces excellent reading results, providing an interface between the machines, transport components and the PLC on the one hand, and the warehouse management software and the order processing system on the other.

Sleeve identification with A+F machines

A+F, from Kirchlengern in Germany, is a leading supplier of end-of-line packaging machines and systems. Seeking flexibility when switching between codes, reliable omnidirectional reading characteristics and a compact design, A+F opted for the Lector620 Professional image-based code reader when equipping its SetLine sleeving systems.

As yoghurt manufacturers, for example, switch between different products and container sizes, the corresponding sleeves which end up on the yoghurt pots are identified by eight code readers and confirmed as correct before being unfolded in the sleeve application station. This means that a raspberry yoghurt will not end up with a sleeve for a lemon yoghurt.

Although the position and orientation of the barcodes and 2D codes vary, the Lector620 Professional can identify them with very little trouble. Furthermore, it monitors the print and contrast quality of the codes on the sleeves. If the code readers catch several incorrect sleeve types, the system stops and the machine operator checks the infeed of the carton magazine. This enables A+F to achieve a high degree of packaging reliability and avoid waste.

Quick reading rates are the bottom line

Laser-based barcode scanners from the CLV6 series feature an extensive depth of field and reading field width. The wide aperture angle enables one device to cover the majority of conveyor belt widths. With excellent reading properties and reading rate of 99.98%, the barcode scanners ensure that data is gathered reliably — even with poor quality or damaged barcodes.

Reliable reading is guaranteed with foil-protected codes and other reflective surfaces, collecting relevant product data in a time-efficient and cost-efficient way. With 4Dpro compatibility and a high level of user-friendliness, the barcode scanners enable flexible product changes without disrupting the process flow significantly. The high scanning frequency allows fast process speeds when identifying containers, for example, and the scanner can handle large reading distances and low-contrast codes — which may occur when identifying pallets, for example.