Cashew poison, a concern for those handling the raw seeds, is a lesser-known hazard outside the industry. Urushiol, the toxic resin found in the double shell of a cashew is responsible for causing allergic skin reactions to poison ivy.
The silver lining is that most consumers never encounter truly raw cashews since the 'raw' cashews available in stores have been steamed to remove this harmful substance. Understanding the journey from seed to snack can provide peace of mind when enjoying this popular treat.
Urushiol is the same chemical found in poison ivy, and it is present on the leaves of the cashew tree as well as in the raw cashew shell. Processing raw cashews can be a laborious and nightmarish ordeal, and people who work in cashew processing plants tend to exhibit greater allergies to cashew shells over time. There is a high incidence of skin rashes among people who either harvest or process raw cashews. Greater sensitivity to urushiol can lead to extreme allergic reaction when raw cashews are ingested, and anyone allergic to poison ivy could potentially have a fatal reaction to eating true raw cashews.
This is why we don’t eat strictly raw cashews. Even the “unroasted’ varieties are steamed to release urushiol from the nut and make it safe to eat. Certainly, those raw cashews sold as raw have been processed to remove urushiol, so there is no danger in consuming them. As nuts and seeds go, safely prepared cashews actually cause very few allergies, especially when compared to nuts like walnuts or legumes like peanuts.
The cashew tree is a New World food, and it’s certainly a testament to the ingenuity of New World races that we even eat “raw” cashews. At some time, pre-dating written history, the people of Brazil figured out that the fruit surrounding the cashew “nut” could be eaten, but the shell could not. Also, early Brazilians were able to understand that the nut could be used when steamed or cooked. This may have been a trial and error process, with many people getting ill from error testing, but it ultimately brought us to the enjoyment of one of the most popular nuts, now grown in many places throughout the world.
Though cashew nut oil from the shells is not safe to consume, it does have uses. It may be distilled and used to line brakes to provide friction, or may make up one of the resins in epoxy finishes and coatings. Touching these extractions from raw cashews may create rashes, but this is less common, since the oils and resins made from them undergo extensive processing.
Can You Eat Raw Cashews?
Cashews pulled straight from the tree are not what you think of when you see the nut in the supermarket. This nut is actually a seed found within a two-layer shell. Unfortunately, just as there are hazards in touching these shells, they are also dangerous to eat.
What Makes Raw Cashews Dangerous?
Besides containing urushiol, a skin irritant, the shells also have two other components that are toxic to ingest. Anacardic acid causes rashes similar to urushiol, and phenolic resin is a chemical sometimes found in insecticides. These oils in the shells can leach into the cashew seed, making it dangerous to eat the raw nut even after removing it from the outer layers. This is why companies steam cashews to clear the oils before selling them for consumption.
What Happens If You Eat Raw Cashews?
If you eat a raw nut, you may experience a variety of symptoms. If you have an extreme allergy to urushiol, you may experience throat swelling, leading to an anaphylactic episode. Other more minor reactions include nasal swelling, throat itching, upset stomach and dizziness. It's best to avoid exposure and not take the risk of a severe reaction.
Can You Eat Cashew Fruit?
You may be surprised to know that the cashew nut grows below a bulb commonly called a cashew apple. This yellow or red pseudofruit isn’t actually a fruit because it doesn’t contain any seeds. The only seed is the part of the plant you know of as a nut. Even though the attached seed is not edible without processing, you can safely eat this fruit bulb. However, it rots within a few hours once it’s separated from the seed, so you need to get close to the source for the freshest fruit.
How Does It Taste?
The accessory fruit that sits atop the cashew seed is very juicy and can be eaten raw or cooked. It has a flavor similar to a cross between grapefruit, strawberry, cucumber and mango. The meat of the apple is fibrous and spongy yet soft to eat. The raw fruit has a strong astringent flavor that may taste different from anything you’ve ever eaten.
Is Cashew Fruit Healthy To Eat?
Not only do cashew apples taste nice, but they also have many health benefits. The bulbous stem of the cashew fruit contains a lot of fiber, which makes it helpful for improving digestion. It also has a high amount of magnesium and vitamin C and good iron, copper and potassium levels. When made into a juice, the mixture relieves throat irritations and boosts your immune system. Additionally, the fruit contains tannins, which reduce inflammation, control blood sugar levels and promote a healthy brain.
Where Can You Buy Cashew Fruit?
If you want to purchase some of these tropical fruits, they are hard to find in global markets because the skin is so thin it doesn’t transport well. If you visit countries that export cashews, you may be able to find this sweet treat at a local vendor. A few retailers have discovered they can remove the pulp from the peel and sell it frozen.
How Can You Eat a Cashew Apple?
Communities that grow cashews have come up with some unique ways to eat the apple. Since this part of the plant is grown mainly for the nut, using the fruit prevents a large part of the harvest from being wasted. Over time, people have become creative with their uses of the cashew apple. Some popular products created from this fruit include:
- Alcoholic beverages: In India, people use juice and pulp to make a fermented drink called feni. The liquid gets distilled many times and develops into a very strong alcoholic drink. Traditionally, this process involves stomping on the fruit with bare feet to get as much juice and pulp from the apple as possible. Other cultures in Mozambique and Tanzania also use the fruit to produce alcoholic beverages.
- Vinegar: Apples are an excellent choice for making vinegar, which works well for marinating and pickling.
- Jam and syrup: People use the fruit's pulp and juice to make jams, spreads and syrups. Boiling it down and mixing it with a sweetener makes for a delightful treat.
- Juice: Freshly squeezed juice gets sweetened by mixing it with sugar or other fruit juices or blending it into a smoothie.
- Sweet curries and stew: The sweetness of the fruit pairs nicely with the deep aromatic flavors of cinnamon and turmeric in curry. The fruit is dense enough to still have a nice bite to it after being cooked.
