‘Smells a bit honky’: Rachel Roddy tests the best (and worst) supermarket pesto

It is true that pesto is an incredibly useful jar to have in the cupboard. It is also true that pesto is a hard thing to preserve in a jar in a way that tastes nice. This is especially true if you are working to keep costs down – as consumers, we can all do ballpark sums for the cost of herbs, nuts, cheese and olive oil. I think one of the problems lies with the herbs’ tendency to get a bit muggy during processing, though some makers are doing quite a good job.

Just to be clear about nomenclature: pesto, from the Latin pestare, meaning to pound, is a generic word for a whole group of similar mixtures, the general guidelines being to mix any herb with any nut and with any cheese, then pour oil over the top. All the pestos I tasted fall into this general category, and they are called green pesto, Italian pesto or basil pesto. Pesto alla Genovese, on the other hand, is a specific mixture of basil, pine nuts, garlic, parmesan, pecorino and olive oil.

I am a fan of pesto both generic and specific, and make it all the time; I also like to have a jar in the cupboard. So I found this comparative tasting fascinating, not least for the ingredients lists. I tasted the pestos straight from the jar and stirred through hot pasta, because heat and a splash of the pasta cooking water play a major role: they melt the cheese, awaken the aromas (good and not so good) and change the pesto’s consistency. And remember, jarred pesto can also be spruced up with fresh herbs, more olive oil and, the saviour of so many things, an extra shower of cheese.

The best supermarket pesto

Best all-rounder
M&S green basil pesto

_{£2.20 for 190g at Ocado}
★★★★☆

Has both pine nuts and cashews, and the sweet smell of cheese gives way to grass and herbs, which is a good start. I was only let down slightly by its sweetness. Good mixed with pasta, too; the heat brings out the herbs, but also more of that sweetness, sadly. That said, it stays well-balanced and free of the muggy and metallic taste that haunts many jarred pestos. I like this.

Best splurge
Filippo Berio classic pesto

_{£2.80 for 190g at Tesco}
★★★★☆

I am always happy to see olive oil in the ingredients list, as well as a mix of grana padano and pecorino. This has a nice aspect and an appealing colour. It’s quite salty, but the basil is also very present and nicely spicy, and I like the rustic consistency. It improves when mixed with pasta, with the heat waking up the basil almost aggressively; you can also really taste the cheese. Very decent.

Best bargain
Lidl Baresa green pesto

_{99p for 190g at Lidl}
★★★★☆

The first impression is oily, but the pea-green colour, herbal smell, consistency and rounded flavour make for a well-balanced pesto. It’s even better with pasta – the balance maintained as the heat warmed the oil, including a lemon note that I quite liked.

And the rest …

Tesco green pesto

_{99p for 190g at Tesco}
★★★☆☆

When tasting this pesto with a spoon, the first flavour I get is peas, which is explained in the ingredients list: pea fibre! It actually turns out to be quite nice – vegetal and grassy – plus there’s a good balance of ingredients, especially the cheeses (pecorino and parmesan). Once mixed with pasta, the flavours stay balanced, but they’re a bit subdued: the basil emerges, but the cheese struggles to keep up – I added more.

Sacla classic basil pesto

_{£3.35 for 190g at Sacla
£3.35 for 190g at Sainsbury’s}
★★☆☆☆

Leads with cheese – pecorino and parmesan – and so much so that it smells a bit honky. Beyond that is the scent of olive oil and a faint herbal note. Cheese dominates the flavour, too, and overwhelms everything else. I did not add more when I had this on pasta.

Aldi Cucina basil pesto

_{99p for 190g at Aldi}
★★☆☆☆

I know how hard it is to conserve the colour of basil, so I tried not to be dissuaded by the muggy-green look or the slightly wet-grass smell (not unpleasant). I like cashews in pesto and also appreciated the slightly spicy note. Same observations apply when added to pasta.

Waitrose basil pesto

_{£1.90 for 190g at Waitrose}
★★☆☆☆

Just a few ingredients, a pleasing, vivid green and, with no added sugar, a startling contrast to the sweet pestos I tasted. No sign of basil, or indeed anything green or herbal, and a gritty, sandy texture. Things improve when this is mixed with pasta and heat: the herbs arrive and, although it comes out a bit milky, the flavour stays rounded. Good for kids, maybe, and would be helped along by cheese.

Sainsbury’s green pesto

_{£1.10 for 190g at Sainsbury’s}
★☆☆☆☆

Dull green and not too pleasing a smell. The taste is overwhelmed by a pappy consistency – explained, maybe, by the use of potato flakes (don’t get me wrong: potato can be great in pesto). At first, I thought the flavour was absent – neither sweet nor savoury – but then it arrived in a metallic aftertaste. Not improved by pasta or heat, but helped by loads of grated cheese.

Co-op green pesto

_{£1.40 for 190g at Co-op}
★☆☆☆☆

Despite the fat in the cashews, vegetable oil and cheese, this is a strangely fatless pesto; it’s a bit weedy, and that goes for its colour, too. But I am an optimist, so hoped that heat and pasta might help. They did not, and may have made things even worse. Maybe I should have spruced it all up with a bit of butter, extra-virgin olive oil or loads of cheese.

Rodolfi pesto alla Genovese

_{£1.75 for 190g at Iceland}
★☆☆☆☆

An oily aspect, but it at least smelled of basil, which made me hopeful. I was disappointed, however, by the sweet, slightly pappy flavour and oily aftertaste. I hoped the basil scent would come out with heat, and that cheese would wake it up, but no such luck. Mixed well with the pasta, though, and I helped it out by adding grated cheese and black pepper.

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