The Konjac Family: Its Surprising Relatives
Explore the unexpected botanical lineage of the konjac plant, connecting this source of edible fiber to familiar ornamental plants and famously unusual flora.
The konjac plant, Amorphophallus konjac, is a perennial native to East and Southeast Asia cultivated for its large, starchy corm. This corm is the primary ingredient in food products like the gelatinous Japanese staples konnyaku and shirataki noodles. Beyond its culinary uses, konjac belongs to a botanical family that includes many common houseplants and other unique specimens.
The Arum Family (Araceae)
Konjac is a member of the Araceae family, also known as the aroids. This family is defined by a floral structure called an inflorescence, which consists of two main parts: the spadix, a fleshy spike of tiny flowers, and the spathe, a large, modified leaf that surrounds it. This arrangement is easily visualized in the common peace lily or calla lily.
Many plants within the Araceae family also share a defense mechanism involving calcium oxalate crystals. These needle-like crystals can cause significant irritation to the mouth and throat if the plant material is consumed raw. Proper cooking is necessary to break down these crystals and make certain species, like konjac, safe for consumption.
Notable Relatives of Konjac
Many popular ornamental houseplants are close relatives of konjac, including the Peace Lily (Spathiphyllum), various species of Philodendron, and Monstera deliciosa. These plants are prized for their attractive foliage and ability to thrive indoors, making them staples in homes and offices.
Within this family, there are also other plants cultivated for their edible parts, most prominently taro (Colocasia esculenta). Taro is another corm-producing aroid that is a food staple in many tropical and subtropical regions. Like konjac, taro’s corm must be cooked to be edible.
A famous relative of konjac is the Titan Arum (Amorphophallus titanum), often called the corpse flower. This plant belongs to the very same genus, Amorphophallus, making it one of konjac’s closest relatives. The Titan Arum produces one of the largest unbranched inflorescences in the world and emits an odor of rotting flesh to attract pollinators.
The Unique Qualities of the Konjac Plant
The primary distinction of Amorphophallus konjac comes from the specific composition of its corm. The corm is rich in a soluble, dietary fiber called glucomannan. This substance has the ability to absorb large amounts of water, forming a viscous, gel-like substance that makes it valuable for food production.
The process of creating food from konjac involves drying and milling the corm to produce flour, which is then mixed with water and a coagulating agent. This mixture is heated and cooled to form a firm, gelatinous cake known as konnyaku. This block can be sliced or shredded into translucent noodles called shirataki, which are valued for their texture and high fiber content.
The properties of glucomannan fiber are what set konjac apart from its ornamental relatives. While they all share the Araceae flower structure, the konjac plant’s utility is derived from the chemistry of its corm. This focus on its fibrous tuber has established its unique place as a food source.