I doubt if you’ve ever shelled a cashew. Think about it. Any images of shelling cashew nuts in your childhood? Didn’t think so. Cashews aren’t your average nut. I thought about this one day after a trip to the store to replenish my trail mix. Why can’t you buy cashews and shell them yourself? Thanks to the handy-dandy interwebs, I got my answer, and it’s fascinating.
Cashews are native to Brazil, but are grown all over in tropical regions, especially India and Africa. The Portuguese took the plant to India to help with soil erosion (the plant has a massive root system) in the mid-1500′s and Indians fell in love with the plant, using it widely in their cuisine. Odds are, the cashews you buy in the store are from India or Brazil – in other countries, processing the nut is both labor intensive and beyond their technical infrastructure. The nut is just thrown away while the fruit is consumed, sometimes on the spot. Cashews are not grown commercially in the US, because they have no tolerance for cold weather (there may be a few novelty trees in Florida). There’s a $400 million import market for them. 31% of Americans rated cashews as their favorite nut.
The cashew grows on a rather unremarkable looking evergreen tree that is related to the mango tree, pistachio tree, poison ivy and poison oak. It’s a generally bushy, low branched tree that might reach 35 feet. You’d never guess a tree this average looking could produce such an unusual fruit. It blooms with yellowish-pink flowers, and the nut has a double shell with a spongy honeycomb tissue in between that’s toxic. It’s a lot like poison ivy and will blister your mouth. The nut develops first and then a pear-shaped fruit forms that is about 3 inches long ripens to a yellow, juicy appendage above the nut shell. The trees flower for about 2 weeks at the beginning of the dry season (May in India and October in Brazil), and in 2 or 3 months you’ve got fruit. What makes the cashew weird is that the seed is outside the body of the fruit. The fruit is called a pseudo-fruit, or commonly, an “apple.” The nut hangs from the bottom of the apple. In its pre-processed state, the shell of the nut is leathery, not brittle, like most nuts.
When ripe, the apple and nut fall together from the tree. They are collected by hand from the ground. The apple can’t be transported any distance because it is very fragile and spoils quickly. The fruit will rot if left on the ground for a day, so at harvest time daily walks are made through the groves. As a fresh fruit, you can chew them, swallow the juice, and spit the fibers. They are bitter and give you the dry mouth because they’re high in tannins. But cooked, dried, candied, or made into wine, they are apparently pretty tasty. Before the fruit falls to the ground, it is poisonous, they can’t be picked early and ripened while in transit
There are a couple of ways to get to the nut we all love. The nut can be washed in water and stored in heaps for a couple of days. The shell eventually ruptures and the poison runs out. Then they are roasted in a large cylinder to burn off any remaining toxins. Or, the nuts can be dried in the sun and stored (for up to two years) for processing. When it’s time to process them, they are re-hydrated and roasted in a large rotating cylinder. That burns most of the toxic oil off.
There is actually a very good market for the toxic oil. It is used to termite proof wood, in the production of polymers in the petroleum industry and in the automotive industry as a component in brake linings that reduces squeaking. Some roasters are rigged with a trough that collects the oil and maximize profit in the process.
The nuts are usually shelled by hand to get more whole nuts and fewer pieces. But wait, we’re not done yet. They still have to be dried again and peeled by hand. Finally, they are re-humidified vacuum packed in 25 pound cans filled with CO2. A can of cashews sold in India in 2008 for about $2.20.
“Walter D’Souza, former chairman of the Cashew Export Promotion Council of India, said that
manufacturers are not being paid on time by purchasers. Seventy per cent of exported kernels
are sent to the United States and Europe, where ‘purchasers have problem with their bankers’.”
– The Hindu, India’s National Newspaper, December 3, 2008.
Once they get shipped to the US, they are usually roasted, salted and packed into smaller quantities. Cashew farming is hazardous and labor intensive. Our favorite tasty treat is harvested and processed by mostly poor tropical countries that have a surplus of manual labor. There’s no other way to do it. There’s no other place the cashew tree will grow.
So I guess that satisfied my curiosity. But now I’m worried about the toxic oil, the cashew trade, cashew futures, and all the poor people who harvest, roast, shell and pack the cashews. I also want to know what cashew apple wine tastes like. It is called Feni in India, and available at sendwine.com for $65 (including shipping), but I’m going to look for an Indian store and see if I can get some there.