UK supermarkets use ‘substitute’ ingredients in own-brand pesto

British supermarkets are selling own-brand pesto products that contain substitute ingredients which are cheaper, according to an investigation carried out by consumer watchdog “Which?”.

Pesto sauce, which has become a staple food in Britain, is traditionally made with basil, pine nuts, parmesan and olive oil.

Pesto is a sauce originating in Genoa, the capital city of Liguria, Italy.

However, according to Which?, the own-brand pesto products they examined sold by Asda, Co-op, M&S, Morrisons, Sainsbury’s, Tesco and Waitrose contained cheaper alternatives in their products.

All of the standard pesto products sold by the supermarkets were made in Italy and contained between 42% and 49% basil, but were found to contain cheaper ingredients in place of the traditional elements, such as cashew nuts instead of pine nuts, or a mix of both. Olive oil was also found to be substituted with sunflower oil while parmesan was replaced with less expensive Grana Padano and Pecorino Romano cheeses.

The consumer watchdog found that all standard pestos, apart from Waitrose, used thickeners, such as potato flakes, nut flour, vegetable or even bamboo fibres.

Standard pesto from Sainsbury’s, Tesco and the Co-op also contained sugar.

The watchdog also reviewed premium pesto sauce products, advertised as “pesto alla Genovese”. Of the five that the agency looked at all products contained between 38% and 50% basil, extra-virgin olive oil, Parmigiano Reggiano (parmesan) as well as pine nuts. However, the Morrisons, Sainsbury’s and Tesco products also contained vegetable or bamboo fibres as thickeners, in addition to added sugar.

Nikki Stopford, director of research at Which?, said: ‘Pesto has become a staple food in the UK, but our research shows that many shoppers may be getting more than they bargain for when it comes to the pesto they are buying – and not necessarily in a good way.

‘Our advice is not to assume that all pesto contains the same traditional ingredients. Check the ingredients list if authenticity is important to you, or if you are trying to avoid certain contents, such as added sugar.’