Everyone eats almonds, walnuts, peanuts – why do we know so little about nuts?
The next time you’re at a party and absentmindedly grabbing a handful from a bowl, know that there’s a rich history behind these nuts, legumes and seeds. (Yes, they're not all nuts.)
Charles Tebbutt picks up a ripe walnut from the sodden ground. Around us are 120 varieties of walnut tree, planted as an experiment nearly two decades ago. Some have died, some have disappointed and just a few have taken advantage of the Kent soil, to the point where they now throw off tens of kilos of nuts each autumn.
“These Fernor ones are really, really rich. They’re almost cheesy,” said Tebbutt, an ecologist who sells nuts in London’s Borough Market. He pulls the green husk of another variety of walnut, the Bardwell, from the brown shell, and encourages me to do likewise.
“Be careful, because it will stain your hands.” My hands are already brown. Is it permanent? I asked.
“A good couple of weeks.”
The Romans used the tannins from walnut husks to dye clothes. They also threw walnuts at weddings as a symbol of fertility, and tried using them to treat baldness. But this wasn’t why I had come to East Malling.
Discerning eaters are now practically experts on where much of their food comes from. Nuts, meanwhile, are the treat of which few questions are asked. This year, as the first chestnuts appeared, it occurred to me: I had no idea where or how nuts were grown.
‘A FOOD OF EDEN’
I had scoffed a lot of them at cocktail parties. I had thought that nuts were wonderful things: Indulgent but healthy, sophisticated but substantial, fancy but not too fancy to gorge on while watching football.
But until I visited the walnut orchard at East Malling Research Station, I would not have recognised a walnut in its husk.
Nor, until I googled it, would I have been able to pick out a group of pistachios growing on a tree.
I have never stopped to laugh at a cashew tree, whose nut grows on the bottom of a tropical, apple-shaped fruit, looking a bit like genitalia. I never realised that Brazil nuts grow together in pods that weigh up to 2.5kg, which only one animal, a large rodent called the agouti, can gnaw open. (Humans use machetes or axes.)
In my defence, it turns out that nuts are barely grown in Britain. Most of ours are imported from California, China, Turkey and beyond. We are surrounded by conkers from horse chestnut trees but the sweet chestnuts we eat come from Italy, France and Spain.
Most foods have been demonised at some point but nuts are different, said Ken Albala, author of Nuts: A Global History. “I think that’s fundamentally because they’re a food of Eden — they’re unprocessed, they’re nature as it was meant to be.”
Indeed, we should all be eating more of them, according to the EAT‑Lancet commission, an expert group on healthy, sustainable diets. Nuts do not require much land or create excessive greenhouse gas emissions. A peanut has a higher proportion of protein than a beef burger.
The EAT-Lancet “planetary health diet” suggested in 2019 that people should get nearly 300 calories a day from nuts – more than they get from meat and fish. That works out at 50g of ground nuts and tree nuts a day – a handful, or several times the current world average.
Nuts have protein, “good” fat and vitamins. They have crunch and flavour. They are the ideal party guest – the arboreal equivalent of the person who turns up with wine, chocolates and a present for your kids. They are gastronomically extensive and only sometimes astronomically expensive.
BEFORE MADNESS IT WAS FONDNESS
Before the English term being “nuts” was associated with madness, it meant being very fond of something. As president, Barack Obama was very fond of almonds: he used to unwind with a few in the evening. The White House chef stated that Obama ate precisely seven per night. It was taken as a sign of his perfect self‑discipline, until the president later clarified it was a joke.
For those who are not Obama, it is possible to overlook nuts day to day. They are versatile but also superfluous, easily edged aside by crisps. At Christmas, however, nuts are unmissable. They sit there, waiting to be cracked like criminals before interrogation.
A good nut bowl has walnuts, almonds, hazelnuts, pecans and Brazils (most of which now come from Bolivia). The one nut you won’t find in a nut bowl is the macadamia, which is too hard for conventional nut-crackers.
The joy of nuts has come with caveats. When I was younger, nut roast was a dreaded Christmas meal for vegetarians – assumed to be dry and disintegrating. Peanut bowls were being phased out of pubs on the basis that they contained on average a dozen traces of different people’s urine. (I have been unable to find such a study.) Then there was the growth of allergies: One in 50 children in the UK has a peanut allergy and only one in five of them outgrows it.
It always seemed curious to me that people could be highly allergic to one nut and completely tolerant of another. The explanation is that nuts are not very alike.
LEGUMES OR SEEDS?
Botanically, most nuts are not nuts. Peanuts – the world’s favourite nuts, according to the International Nut and Dried Fruit Council, are legumes. In the south of the US, they boil them like beans.
Almonds – the world’s favourite tree nuts, according to the same report – are seeds. Walnuts and pine nuts are also seeds, while coconuts are drupes, a type of fruit. A bag of mixed nuts is therefore like a top Premier League team – its far-flung components thrown together in a way that somehow works.
The best nut I have tasted was a hickory smoke-seasoned almond, sold by snacks company Cambrook. Its flavour was not dissimilar to the best bacon. The raw nuts themselves, as long as they’re of decent quality, are “not that distinguishable”, said Angus Cameron, Cambrook’s co-founder. What matters is the processing: While most roasted and salted nuts are fried on a belt that moves through oil, Cambrook bakes its nuts instead. The seasoning comes from condensed hickory smoke.
A few decades ago, snacking nuts were mostly just salted. Now they mirror culinary trends. “We’ve had quite a lot of success with truffle-flavoured nuts,” said Cameron.
But nuts are not just snacks. They are pressed into oils or folded into main meals, salads and sauces: in pesto, on pizzas, whizzed into gazpacho.
STEP ASIDE, ANIMAL FATS
Part of their attraction, especially in an age of rising vegetarianism and veganism, is their ability to replace animal fats. John Harvey Kellogg, the American surgeon who invented Corn Flakes and advocated vegetarianism, popularised peanut butter in the 19th century as a substitute for cow’s butter.
Today Alexis Gauthier, chef patron at London’s Gauthier Soho restaurant, uses walnuts in his vegan version of foie gras. “The walnut has this texture that doesn’t disappear. It’s almost juicy with fats,” he said. “We break it but we don’t blitz it. We retain a bit of structure.”
Elsewhere, walnuts appear in desserts and salads. French restaurants often combine hazelnuts and chocolate. They deploy chestnuts in sugar syrup – the sickly, irresistible marrons glace. With chestnuts, it’s not the texture that matters, but “the richness”, said Gauthier.
Nowhere takes nuts as seriously as California. Almond trees are often grafted on to peach rootstocks and pollinated by billions of bees, which have to be shipped in from elsewhere in the country.
When harvest comes, mechanical shakers grab the trees and toss the almonds on to the ground. By law the nuts then have to be pasteurised in case of contamination from bacteria from the ground. (Many US walnuts are also pasteurised.)
These industrial techniques have made California the source of 80 per cent of the world’s almonds. Almond milk is by far the most popular substitute for cow’s milk in the US, with annual sales exceeding US$1bn (S$1.3bn)
Although almond consumption doubled in the UK between 2013 and 2017, we still eat less than half as many per capita as Americans.
But the pasteurised taste is not to everyone’s liking. “You might as well be eating cotton wool,” said Alexander Hunt, who grows nuts at Potash Farm, in Kent. Moreover, a single California almond requires 12 litres of water, which is not entirely advisable in a state afflicted by regular droughts. The pollination process also kills billions of bees.
TIME TO GET CRACKING
To meet EAT-Lancet’s recommendations for nut consumption, production would have to multiply over the next few decades. Somehow this has to happen without the water stress that California’s producers currently inflict. It also requires farmers to take a leap of faith – investing in trees that won’t mature for several years.
In Europe, most almond orchards are not reliant on truckloads of bees or irrigation. Ken Albala suggested the lack of irrigation leaves them tasting slightly richer and oilier: “A lot of the almonds that we sell in California taste watery to me.”
European walnuts can be harvested in June and July – giving green walnuts, which are pickled or served in jams. The main harvest comes in October. The husks are separated from the shells by machines, then cracked open. They will go mouldy within a few weeks unless they are lightly roasted, which brings their moisture content down from 30 per cent to 7 to 8 per cent.
It would be rather delightful if we could grow more nuts in Britain. Nut-growing at the moment is small-scale to the point of artisanal. A few hundred acres of cobnuts, from the hazelnut family, and a few hundred acres of walnuts are nowhere near enough to meet local demand.
Walnut trees grow on pretty much any well-drained soil in Britain, but squirrels, rabbits, deer and crows often get to the nuts before farmers can. Hunt, who sells walnut trees as well as nuts, says that his customers tend to be “people in their forties who are leaving the city”.
Charles Tebbutt is hoping that more nut production will catch on as a form of sustainable agriculture, with rows of trees planted between crops such as oilseed, barley and wheat, as they are in France and elsewhere. The trees can bring up nutrients from the subsoil, which then fall to the ground in the form of leaves and nourish the soil for the following year’s cereal crops.
“All the evidence suggests it’s viable,” said Tebbutt. “A big part of the work is to professionalise it. It’s about applying the knowledge that’s already out there.” Crack on.
By Henry Mance © 2020 The Financial Times