Supermarkets have always moved with the times. After the recession we wanted affordable luxury, so we got M&S’s ‘Dine in for two’ and its various imitators. These promised us a restaurant-quality meal and a nice bottle of sauvignon blanc for a tenner.

Well, now the times they are a-Brexit, and retail giants are adapting accordingly. Last week Tesco opened Jack’s. Partly it’s a response to the explosive growth of German rivals Aldi and Lidl. Partly it’s an attempt to create a new, patriotic shopping experience for a nation trying to go its own way.

Tesco bosses swear Jack’s is ‘nothing to do with Brexit’. But the clue’s in the name. It’s supposedly an homage to Tesco’s founder, Jack Cohen — but it’s no accident that in-store, you’ll find Union Jacks everywhere, as well as signs telling you that ‘every drop of fresh milk is British’ and ‘eight out of ten products are British’.

How true that is remains debatable; Tesco has found itself in trouble before over its ‘fake farm’ brands, with bucolic names such as Woodside Farms pasted on the shop’s cheap ranges of fresh produce. These farms don’t actually exist, and the meat and vegetables are sourced from all over Europe. Apart from the fact that Britishness isn’t — whisper it — a guarantee of quality, I’m sure I can’t be the only one raising an eyebrow at a few of their claims.

Posters in Jack’s declare ‘All our tea is blended in Britain’ — but so is almost all of the tea you can buy in our supermarkets. Cheap British milk is only available thanks to lashings of EU subsidy. What’s more, a study by the National Farmers’ Union showed Britain cannot produce more than 60 per cent of its own food, down from 80 per cent in the 1980s, and predicted to fall further after Brexit. In other words, there’s only so much British food a supermarket can stock.

Almost as if anticipating this retail apocalypse after Brexit, Jack’s has ruthlessly trimmed the range of products, from Tesco’s 25,000 to a meagre 2,600. Seventy per cent of them are own-brand. According to Dave Lewis, Tesco’s CEO: ‘People want a simple shop.’ The packaging and store interiors feel deliberately nostalgic. It’s as if Tesco were trying to return us to a pre-EU time when we ate more corned beef, less avocado. I’m not sure that’s a recipe for success, particularly in an age when Britons are more food-obsessed than ever.

The products in the first Jack’s stores, in Cambridgeshire and Lincolnshire, are closely price-matched to those of the German budget supermarkets. As in Aldi and Lidl, the central aisle of Jack’s is reserved for non-food bargains, on a ‘WIGIG’ (when it’s gone, it’s gone) basis. The aisles are wide enough that staff can stack shelves continuously. The similarities don’t end there. Where Aldi offers a ‘super six’ of keenly priced fruit and veg, Jack’s has a ‘fresh five’.

Price wars between supermarkets are nothing new. Who can forget the Bean Wars of the 1990s? In response to pressure from Aldi, Kwik Save dropped its baked beans to 7p, a price not seen since 1971. Other supermarkets swiftly responded. Tesco set its at a seemingly unbeatable 3p — only to be beaten by Sanders, a supermarket in Somerset, which paid customers 2p a time to take a tin of beans home with them. Sanders has since gone into voluntary liquidation.

Headline-grabbing bean prices aside, big supermarkets have often struggled when they’ve tried to go cheap. In 2006, Asda opened a new range of Asda Essentials stores, which stocked almost exclusively own-brand products and explicitly aimed to be ‘the cheapest store in town’. It didn’t last long. In 2014, Sainsbury’s joined forces with Netto to open a range of budget stores, only to close them within two years, unable to make the numbers balance.

And what about quality? Aldi and Lidl frequently win prizes for their produce, much of which comes from the EU. Aldi’s £9.99 gin has been voted the best in the world, and both chains were praised for their cheese, cereal, bread, coffee, biscuits and more at last year’s The Grocer awards. They frequently claim victory in blind taste tests. The verdict on Jack’s is mostly still out — although food campaigner and writer Jack Monroe described their cheese as ‘absolutely awful’ in the Guardian.

Which leaves the question: should supermarkets try to be patriotic at the expense of variety? Tesco’s story is an immigrant one: Jack Cohen, born Jacob Kohen, was the son of Polish Jewish immigrants, but changed his name to John Edward Cohen at his bank manager’s suggestion. Once he entered the grocery business, he was known as ‘Slasher Jack’ for his ‘pile it high, sell it cheap’ approach. But the later triumph of supermarkets was predicated not just on cost but on the fact they replaced simple stores and offered more choice. With Jack’s, Tesco seems to be saying that less is more. Is that what Brexit Britain really wants?

It's as if Tesco were trying to return us to a pre-EU time when we ate more corned beef, less avocado

Olivia Potts writes the Vintage Chef column for Spectator Life. Next week, she launches Table Talk, a new Spectator podcast.