Oliver Cahn, technical architect at Tesco, said the supermarket gives each of its products an electronic "emergency product withdrawal" flag, set at the mainframe level.
In the event of a safety alert, these flags can be "raised" by Tesco's product buyers, resulting in a report automatically being sent over the company's wide area network. This report is printed at the stores as a high-priority print job, alerting staff to remove products from shelves and warehouses.
Cahn said, "Should any such products not get removed by that process, the same flag gets checked when the product is scanned at the till, and the till operator receives a large red message box saying that the product cannot be sold."
Wal-Mart-owned Asda used a product tracking system it co-developed with IT services firm Ramesys in 2001 to speedily withdraw products.
The system, Webtraqs, is an interactive web-based product that can be accessed by all of Asda's suppliers across the world. It uses a database of hundreds of thousands of Asda-branded products, detailing elements including ingredients, suppliers and nutritional information.
Asda said Sudan 1 caused the biggest ever product recall for supermarkets in the UK and IT systems were key in helping the store remove 74 products within 24 hours of the supplier alert.
Although the major retailers coped well with the Sudan 1 scare, it presented a challenge for smaller retailers and suppliers with less sophisticated IT systems. These firms could struggle to meet future legislation on food safety, according to Elsa Lion, an analyst at Ovum.
Forthcoming European Union legislation will enforce the tracking of every ingredient in a product. "The burden will be on every one in the chain," said Lion.
She advised small retailers to implement some sort of supply chain system, and at the minimum, to introduce barcodes. "At least then you have the possibility of tracking products," she said.