India, 1870. Struggling to cope with the relentless heat, a group of British Army officers take refuge in a tea house. To help them cool down, they order a quintessential English dish: crustless, dainty sandwiches containing paper-thin slices of cucumber. To drink, a steaming pot of freshly brewed Darjeeling tea.
It’s not what most of us associate with refreshment on a hot day. But when the British colonised the Indian subcontinent in the late 19th century, they brought cucumber sandwiches – popular among the upper classes back home – to the Raj. They found that the combination of succulent cucumber and buttery bread was more than just a taste of home: it helped them keep cool in the sweltering heat.
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So it’s no surprise that the cucumber sandwich has been named the world’s coolest food. According to scientists from the American Chemical Society, it is the best thing to eat to regulate our body temperature and avoid dehydration during a heatwave. And it works even better washed down with a cup of tea.
Foods we might expect to quench our thirst – such as ice cream or chilled water – are less effective, says Sara Risch, a researcher for the society. This is because cold foods send parts of our body into shock, causing them to shut down and our temperatures to shoot up. Juicy fruit and vegetables, by contrast – like cucumber, watermelon and celery – have a high water content and natural cooling properties.
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So what makes the cucumber sandwich so special? Although cucumbers originated in India more than 3,000 years ago, putting them in a sandwich is very much a British invention. The crops arrived in England in the late 14th century, but they weren’t put in sandwiches until the Victorian era, when they were served during afternoon tea. Because of its low nutritional value (cucumbers are 95 per cent water), the dish was popular among the upper classes as a pre-dinner snack; the lower classes preferred not to waste energy on something with so little protein.
In Edwardian times, plentiful coal and cheap labour meant that cucumbers, grown under glass covers, could be produced in England all year round, not just during the summer. For the past 200 years, the Lea Valley in Hertfordshire, home to Sicilian farmers producing 80 million cucumbers a year, has been the cucumber-growing capital of the UK. As the domestic industry grew, the sandwiches became a staple of high tea, and news of their refreshing qualities reached colonialists in India, Africa and Australia.
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Cucumber sandwiches soon became associated with the opulent way of life in the Raj. They were served to royal guests at Queen Victoria’s Golden Jubilee in 1887 and as lunch to first-class passengers on Indian Airlines flights. In Oscar Wilde’s play The Importance of Being Earnest, Algernon Moncrieff prepares stacks of them for Lady Bracknell’s visit. “Why cucumber sandwiches? Why such reckless extravagance in one so young?” asks a bemused Jack Worthing.
But we weren’t always so fond of cucumbers. “A cucumber should be well sliced, dressed with pepper and vinegar, and then thrown out as good for nothing,” said the author Dr Samuel Johnson. In the 17th century, the cucumber (technically a vine-growing fruit) was given the nickname “cowcumber”, as many thought it was only suitable for cows to eat. It was even thought to be dangerous. “Mr Newhouse is dead of eating cowcumbers,” wrote Samuel Pepys in his diary in 1663.
There are now many variations on the original sandwich. There’s tuna and cucumber; egg and cucumber; even an American spread called “Benedictine”, made from puréed cucumbers and cream cheese. But the recipe for a perfect cucumber sandwich is the subject of much debate. Mayo or no mayo? Crusts on or off? According to the US scientists, only one formula will keep us cool: wholewheat bread, crusts left on, with healthy chunks of cucumber, a “slab” of mayonnaise and sea salt on top.
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Traditionalists won’t be happy. They like them the British way: juicy portions of cucumber, gently dried of excess water, sprinkled with salt and a dash of lemon juice, and served between two triangular slices of lightly buttered white bread. Crusts off, of course – and never any mayo, although perhaps a drizzle of olive oil. It’s the fresh, zingy taste of English summertime contained in a single bite.
And the real reason it’s so refreshing? Sir Compton MacKenzie, the writer and Scottish Nationalist, had his own explanation. He described a typical British tea party as follows: “You are offered a piece of bread and butter that feels like a damp handkerchief – and sometimes, when cucumber is added to it, like a wet one.”
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