Cashews are undoubtedly marketed as nuts, sold alongside other nuts at the store and within “nut” mixes. However, like other foods that don’t neatly fit into neat categories (tomatoes, cucumbers, strawberries) the cashew walks a fine line between nut and fruit.
Are cashews considered a fruit? Technically, the cashew is a kernel or a seed, coming from the cashew fruit that grows on the evergreen cashew tree. They are botanically classified as a drupe seed.
Cashew apples contain a thick, toxic shell that also causes a skin rash when exposed to the skin. This shell must be removed to get to the kernel, or seed, which we know as the cashew. The fruit portion typically will get used in jams.
The fact that cashews must be extracted from a shell inside the fruit further points to the direction that cashews are kernels or seeds.
What is a Drupe?
Drupes contain a fleshy outer layer that surrounds the stone or pit. The prime examples of this are apricots, avocados, and peaches. The stone or pit then has a seed or kernel inside that is edible.
Of course, cashews are slightly different than other drupes in that their toxic shell grows outside of the fruit rather than inside. Additionally, the edible fruit portion grows after the kernel has matured.
Like a Legume, But Not?
Cashews are similar to legumes because legumes are plants that produce edible seeds, like peas, edamame, or beans. These seeds typically grow in a pod alongside other seeds. Peanuts are actually a legume. This is, however, the same logic that chocolate is a vegetable because it comes from a bean.
Cashews, however, are within that hard, toxic shell and are thus not a legume.
Similarities to Nuts
The main reason why cashews are considered nuts is because they have a lot of nutritional similarities to other nuts like chestnuts and hazelnuts. They are rich in proteins and healthy fats and can be substituted for other nuts in granolas, trail mixes, nut butters, and nut milks.
Fun fact, many other “nuts” are actually drupes like cashews. Almonds, pecans, pistachios, and walnuts are all drupes.
To ease some confusion, any nut that is considered a drupe is therefore considered a fruit. Since peanuts are a legume, they are considered a vegetable. Tree nuts are also considered fruits because they have an edible seed encased in an inedible hard shell.
In the cooking world however, the classification of nuts is much more loose. Many of these drupes, legumes, and true nuts are considered nuts due to similar nutritional values, tastes, and applications.
Summary of Cashew Oddities
- Grows on a tree that has evergreen leaves
- Has a pit like mangos or peaches, but the pit grows outside the fruit and matures first
- Acids in the pit cause a rash like poison ivy
The Cashew Fruit
The cashew apple is bulbous and looks either pear-shaped or ovular. They range in color from golden-yellow to red, which might be how they got their “apple” name.
The fruit is sweet and tropical tasting, but will not last off the vine more than a day or two off the vine which is why you won’t commonly see it in the produce section, but rather mixed into jams or juices.
Many people liken the taste of cashew apples to a blend of mangos, strawberries, cucumber, and bell peppers. The fruit grows year-round in tropical climates and is native to Brazil.
The shell portion is attached to the bottom of the fruit. It is double-hulled and kidney-shaped. This is where the anacardic acid is that causes the skin rash.
Because the shell is outside of the fruit, unlike mangos and peaches, cashew fruits are considered false fruits or pseudo-fruits. Nevertheless, the fruit is a great source of vitamin C, magnesium, copper, potassium, iron, and fiber.
The Cashew Nut
Cashews are known for their slightly salty flavor and almost buttery texture. They can easily be made into a butter. Cashews are the typical substitute for peanuts if someone has the peanut allergy, but not a full-blown nut allergy.
How Cashews are Harvested
So because cashews are encased in a toxic shell that causes skin rashes, they are a bit hard to harvest. Interestingly enough, cashews come from the same plant family as poison ivy and sumac, further setting them apart from other types of plants.
However, humans will figure out how to eat almost anything. Cashews are removed using protective gear and special tools. The challenges harvesting cashews present factor into the pricier cost of the edible kernel.
Processing the nuts involves roasting them outside in a special designated pan filled with liquid or sand. The liquid or sand catches the toxic liquid the cashew shells spit out as they are heated up.
After they are roasted, the shells are washed in soap and water to remove any of the remaining toxic oils. Then the shell is cracked, the cashew seed is removed, and roasted one last time just in case.
Benefits of Cashews
Regardless of whether or not cashews are a fruit, a nut, or a seed, eating them has a plethora of health benefits.
- Rich in dietary fiber, as well as many vitamins and minerals linked to offering protection against diseases and cancers.
- Contains monounsaturated fatty acids, which studies have linked to reducing coronary artery diseases.
- Rich in selenium, which assists antioxidant enzymes in your body.
- Have zea-xanthin in them, another antioxidant which helps eyes function better.
- Provide high amounts of iron and copper, which are both important to red blood cell health
- Contains magnesium and potassium which promote lower blood pressure and might also be linked to reducing migraines
While cashews are harvested from a fruit, they are a drupe. The edible cashew “nut” we all recognize and purchase at the store is the kernel, or seed, that comes from the drupe fruit. Additionally, cashew fruits are a pseudo-fruit because the shell containing the seed grows at the bottom of the fruit rather than inside.
Cashews made themselves hard to classify, but the botanical classification eventually landed on seed. When it comes to cooking though, they’re still a nut.