An international food scandal that involves mixing horsemeat with processed beef and then labelling the meat products such as hamburgers and lasagnas as containing 100% beef. Although eating horsemeat itself is not a food safety issue, it's considered a cultural taboo in countries like the UK and the United States. Horsemeat can also contain phenylbutazone or bute, a veterinary drug commonly used for treating horses. Phenylbutazone is not allowed to enter the food chain as it may pose a risk to human health.

One of the reasons that meat suppliers use horsemeat to substitute for beef is that horsemeat is much cheaper compared to beef due to low consumer demand.