“Dozens” of Tesco products the supermarket has price-matched to Aldi are not like-for-like, according to an investigation by BBC Panorama.

Items including chicken nuggets, blackcurrant squash and chicken kievs were found to contain less of their main ingredient compared to their Aldi equivalents, according to the study carried out last month.

Panorama’s research found that Tesco’s chicken nuggets contained 39% chicken compared to 60% in the Aldi version, while its chicken kievs had 44% chicken compared to Aldi’s 57%.

Tesco’s chilli con carne had 15% beef compared to Aldi’s 27%, according to the programme.

Twelve Tesco products were found to have more of the main ingredient.

Tesco told the BBC that it constantly reviewed the quality of its products and had clear processes in place to ensure its price-match products were comparable to Aldi.

It also said a higher proportion of any one ingredient did not necessarily mean it was better quality.

The five Aldi price-matched products found to have the largest difference in the proportion of their main ingredient were chicken nuggets (chicken), chicken kievs (chicken), chilli con carne (beef), cottage pies (beef), and apple and blackcurrant squash (fruit juices).

While Sainsbury’s, Asda and Morrisons also offer Aldi price-matched products, BBC Panorama did not find clear evidence of a pattern of consistent differences in the amounts of main ingredients in their items compared with the discounter’s equivalents.

A Tesco spokesman said: “Since we launched our Aldi Price Match four years ago it has proved very popular with customers.

“We constantly review the quality of our products, and we have clear processes in place to ensure that the hundreds of products that are included are comparable with those sold at Aldi.”