The cashew, a kidney-shaped seed prized globally for its rich flavor and texture, originates from a tree with specific geographic and climatic demands. From its South American beginnings, the cashew tree has been transplanted across the tropical zones of the world, creating a complex global supply chain.
Native Origin and Climate Requirements
The cashew tree, Anacardium occidentale, is native to the tropical climates of northeastern Brazil, specifically the region between the Atlantic coast and the Amazon rainforest. Portuguese explorers were responsible for transporting the tree from Brazil to their colonies in India and Africa during the 16th century, establishing the foundation for global cultivation.
Commercial cashew production requires a frost-free, tropical or subtropical climate with temperatures between 63°F and 100°F. A distinct dry season is necessary for successful flowering and fruit setting. Cashew trees are hardy and tolerate poor soil conditions, often thriving in well-drained, sandy, or lateritic soils where other crops might struggle.
Major Global Production Centers
The center of cashew production has shifted significantly from its native Brazil to the equatorial zones of Africa and Asia, an area often referred to as the “Cashew Belt.” This belt encompasses countries with the ideal combination of tropical heat and a pronounced dry season for fruit development. Today, the largest raw cashew production takes place in West Africa, which accounts for a substantial portion of the global supply.
Côte d’Ivoire is the world’s leading producer of raw cashews, with India and Vietnam consistently ranking as other top producers. Africa leads in raw cashew production, with Tanzania, Benin, and Guinea-Bissau also contributing significantly. However, much of the raw crop harvested in Africa is exported to Asia, where processing capacity is highly concentrated. Vietnam has become a global powerhouse in processing and exporting finished cashew kernels, separating where the crop is grown from where it is prepared for consumption.
How the Cashew Nut Develops
The edible cashew is not a true nut but the single seed of a drupe, which develops in a unique manner on the tree. The true fruit is a small, kidney-shaped structure that grows at the end of a much larger, fleshy, pear-shaped accessory fruit called the cashew apple. The nut develops first, enclosed in a hard shell, and then the stem structure, or pedicel, swells dramatically to form the colorful, juicy cashew apple that hangs above the nut.
The shell surrounding the cashew kernel contains cashew nutshell liquid (CNSL), a caustic oil. This liquid is rich in anacardic acid, a phenolic resin similar to the compound found in poison ivy. Because contact with this oil can cause severe skin irritation and burns, cashews are never sold in their raw, unshelled form. Processing requires careful handling, typically involving high heat or steam to neutralize the toxic oil before the nut is safely cracked, shelled, and prepared for consumption.