Horsemeat has been detected in two samples of ground meat in the US by researchers at Chapman University.

The research, which was published in the journal Food Control, focused on identification of species in ground meat products sold on the US commercial market using DNA-based methods and found horsemen in two samples.

Of 48 samples that were analysed for the study, it found that 10 were found to be mislabelled and of those 10, nine were found to have additional meat species and one sample was mislabeled in its entirety.

Horsemeat – which is illegal to sell in the US, was detected by researchers in two of the samples.

Rosalee Hellberg, Ph.D., Assistant Professor at Chapman University and Co-author on both studies, said that although extensive meat species testing has been carried out in Europe in light of the 2013 horsemeat scandal, there has been limited research carried out on this topic in the US.

“To our knowledge, the most recent US meat survey was published in 1995,” she said.

According to the study, a total of 48 fresh and frozen ground meat products representing a variety of species were collected for the research.

The researchers then tested using a combination of DNA barcoding and real-time polymerase chain reaction (PCR).

The study suggests that the presence of multiple species commonly found in ground meats suggests the possibility of cross-contamination at the processing facility.

Unintentional mislabelling may occur when several species are ground on the same manufacturing equipment, without proper cleaning in between samples, the study found.

The study also indicates the possibility of lower-cost species being intentionally mixed in with higher-cost species for economic gain.

Overall, mislabelling was found to be most common in products purchased from online specialty meat distributors, which showed a 35% rate of mislabelling and included products labelled as black bear and yak burgers, it found.