The cashew, a popular snack, often causes confusion regarding its botanical origins. This article clarifies how cashews grow and explains the distinct components of the cashew plant.
Understanding the Cashew Plant
The cashew tree, scientifically known as Anacardium occidentale, is a tropical evergreen cultivated for its valuable edible seed and its associated fleshy structure. What is commonly referred to as the “cashew nut” is, in botanical terms, the tree’s true fruit, classified as a drupe. This kidney-shaped drupe contains the edible kernel and develops at the end of a larger, pear-shaped structure.
This larger, colorful part, often called the “cashew apple,” is not a true fruit. Instead, it is an accessory fruit or pseudofruit, formed from the swollen stem of the cashew flower. While the cashew apple ripens, the actual cashew seed, enclosed in its hard shell, hangs beneath it. The cashew apple and its attached seed mature together before falling from the tree.
From Plant to Plate: Processing Cashew Nuts
The cashew nut cannot be eaten directly from the tree due to a naturally occurring protective compound. The shell contains a toxic irritant known as urushiol, the same substance found in poison ivy. Direct contact with this oil can cause skin irritation and allergic reactions, making its removal a specialized process.
Processing cashew nuts is complex and labor-intensive, contributing significantly to their market cost. After harvesting, the cashew nut is carefully separated from the cashew apple. The nuts then undergo a heat treatment, such as roasting or steaming, which effectively neutralizes the urushiol.
Following heat treatment, the softened outer shell is cracked open to extract the kernel. This delicate process is often carried out manually, requiring precision to avoid damaging the nut. The kernels are then dried, peeled, and finally graded by size and quality before packaging. This elaborate sequence ensures the safety and edibility of cashews for consumers.
The Cashew Apple’s Role
While the cashew nut receives global attention, the cashew apple also holds significance, particularly in regions where cashews are cultivated. This fleshy, pear-shaped structure displays vibrant colors, ranging from yellow to red, and possesses a juicy pulp. It has a sweet taste, often accompanied by a slight astringency, especially if not fully ripe.
The cashew apple is rich in nutrients, including Vitamin C, antioxidants, and various minerals. In cashew-growing areas, it is consumed fresh or processed into products such as juices, jams, and fermented beverages like Feni in Goa, India.
However, the cashew apple is not widely exported or distributed globally, unlike its famous seed. Its delicate nature and short shelf life (typically one to two days) make long-distance transportation challenging. The fruit also bruises easily, limiting its commercial viability for fresh consumption outside growing regions.