Food writer, author and demo chef Leah Hyslop on the rising popularity of purple foods
When you were a child, you were probably told to eat your greens—but the next generation might well be encouraged to finish their purples.
Wander around Borough Market’s fruit and veg stalls and you’ll see that purple is the new black. There are towering piles of purple cauliflowers, kale, sweet potatoes, corn, garlic and even purple sprouts (though the jury’s out on whether your children are more likely to eat purple brussels at Christmas, I’m afraid). There are candy beetroot with gorgeous pinky-purple swirls right through their centres and graffiti aubergines, their deep colour streaked with lines of white.
Fear not: these colours are not the product of a new world of cross breeding and genetic modification—purple food has existed in nature for centuries. Until the 20th century, carrots were more likely to be purple than orange, and “with a few exceptions, the purple produce we sell are old heritage or heirloom varieties,” says Kath Dawson of Borough stalwart Ted’s Veg. The difference is, in the last few years, producers have started growing enough to fill shoppers’ baskets across the country.
If you look at it from an evolutionary perspective, the sudden enthusiasm for indigo-hued food is a mystery. We eat with our eyes, and it’s long been known that certain colours of food are more attractive than others; red food, for example, tends to suggest ripeness and sweetness, which is probably why so many fast-food manufacturers use it in their logos. But black, blue and purple food was, supposedly, historically avoided because it usually indicated that produce was toxic or rotten.
Rich purple pigments
Unlike our fearful ancestors however, we now know these rich purple pigments usually spell good, rather than bad for the body. At Turnips, purple potatoes now outsell orange and white varieties put together and the modest beetroot, once known mostly to the British as that nasty vinegary vegetable in the jar, is now a fashionable regular on restaurant menus where it’s often served roasted whole. The most obvious explanation for this sudden purple reign is the health benefits they may offer. “All richly coloured foods may provide benefits for your health,” says nutritionist Louise Wright.
But there may be another, more superficial reason for this colourful new trend. In the age of image-driven social media platforms like Instagram, purple food quite simply grabs attention. The Brazilian acai bowl—a bowl of pureed purple acai fruit garnished with fruits, seeds and other nutritious goodies—has become an internet sensation as much for its striking looks as its health benefits. However tasty, cauliflower soup is just never going to go viral.
Professor Charles Spence of the University of Oxford, who has written widely about perceptions of flavour, points out that purple colouring rarely changes fruit and vegetables’ taste in a significant way—it just grabs the eye, like the blue dye used for raspberry drinks since the 1970s. “It’s for look, never for flavour.”
Restaurants and cat walks
Chefs too are leading the charge. For Fred Foster of Turnips, “Many trends start in the fine dining restaurants around Europe and here in the UK. The demand by the great chefs for new and exciting products has led to these varieties being on trend again. And like the fashion industry, it is not until the restaurants or designers display them in their restaurants or cat walks that we see it being filtered down to the high street.” And the high street is going mad for these purple foods. “At first we thought that they were gimmicks, but we were wrong,” explains Fred. “Our team of buyers are now purchasing purple produce direct from UK and European farmers and even from across the Atlantic.”
Shoppers after an impressive dinner party starter or Christmas Day side dish don’t have to do much to make their purple ingredients look spectacular. But the colour of some—such as purple sprouting broccoli and purple beans—can fade after cooking. The trick is to cook them quickly: try frying rather than steaming or boiling, which tends to leach out the colour. Adding acid, like a dash of vinegar or lemon juice to your red cabbage or a squeeze of lime to your stir-fry, can also help preserve the vibrant shade, just like lemon juice stops banana or apple browning in a fruit salad.
Of course, popping a few handfuls of purple kale into your lunchtime salad won’t guarantee good health: any good nutritionist will point out that it’s important to eat a rainbow of veg, from leafy greens to ruby-red tomatoes, to access the full gamut of nature’s nutrition. But there are worse things you can do than add a splash of purple to your plate. If nothing else, it’ll brighten up even the dullest of winter days.