Horse meat eaten without the knowledge of the consumer, due to accidental or fraudulent introduction of horse meat into human food. A 2003 Food Standards Agency (FSA) investigation revealed that certain sausages, salami and similar products such as chorizo and pastrami sometimes contain horse meat without it being listed, although listing is legally required. The 2013 horse meat scandal involved multiple products being recalled from shelves due to unlabelled horse meat in amounts up to 100% of the meat content. The issue came to light on 15 January 2013, when it was reported that horse DNA had been discovered in frozen beefburgers
Tesco site as part of a precautionary security measure. This coincided with several other retailers, including CVS and Walmart Canada, shutting down similar services regarding a security breach at PNI Digital Media. The UK Groceries Code Adjudicator found in a 2015–16 investigation into Tesco that some suppliers paid "large sums of money in exchange for category captaincy or participation in a price review". She found some evidence of benefits which suppliers derive from these arrangements, but also recorded a concern—to be investigated further—as to whether the purpose of the Groceries Code was being circumvented by these payments. Tesco Tesco plc, trading