The Dragon Tongue bean is an heirloom agricultural product distinguished by its strikingly patterned pods. This unique variety of common bean features a mottled coloration of pale yellow and vibrant purple. Beyond its unusual appearance, the bean offers a versatile profile for culinary use, utilized both as a fresh snap bean and a mature shelling bean. This article explores the botanical identity of the Dragon Tongue bean, its nutritional components, preparation methods, and other non-edible plants that share its evocative name.
Defining the Dragon Tongue Bean
The Dragon Tongue bean is a specific heirloom cultivar of the common bean species, scientifically known as Phaseolus vulgaris. This plant is a member of the Fabaceae family, which includes all pulses and legumes, and is typically a bush variety, meaning it grows compactly and does not require a trellis. Its origins trace back to the Netherlands, where it was first cultivated as an open-pollinated heirloom in the 18th century, earning it the alternative name ‘Dragon Langerie’.
The pod itself is the most distinctive feature, characterized by a flat, broad shape that can reach six to eight inches in length. The background color is a creamy yellow or buff, which is generously streaked and mottled with vivid purple or burgundy markings. These stringless pods are harvested for consumption at two different stages of maturity, making it a dual-purpose vegetable. When young, the entire pod is eaten like a green bean, but if left to mature, the pod is shelled to access the fully developed seeds inside.
Key Nutritional Components
As a member of the common bean species, the Dragon Tongue bean provides a robust nutritional profile, particularly when harvested as a mature shelling bean. It is a source of complex carbohydrates and protein, supporting energy levels and tissue maintenance. The bean contains a substantial amount of dietary fiber, which supports digestive regularity and cardiovascular health.
A typical serving contains several grams of protein, making it a valuable component in vegetarian and vegan diets. The presence of B vitamins is notable, specifically folate, which plays a role in cell division and genetic material formation. The beans also supply essential minerals, including iron, necessary for oxygen transport, and magnesium, a cofactor in numerous enzymatic reactions.
The deep purple streaks on the fresh pods are visual evidence of phytonutrients known as anthocyanins, which are potent antioxidants. While the color fades upon cooking, the bean remains a nutrient-dense food. Its composition of protein, fiber, and complex carbohydrates helps promote sustained fullness.
Preparation and Culinary Applications
The versatility of the Dragon Tongue bean allows it to be used in various culinary preparations depending on its maturity. When harvested early, the crisp, tender pods can be eaten whole as a snap bean, offering a nutty and slightly sweet flavor. These young pods are tender enough to be sliced and added raw to salads or served on a crudités platter.
For cooked applications, the beans are often lightly steamed or boiled for just a few minutes to maintain their crisp texture. A notable characteristic is the disappearance of its purple mottling when heat is applied, with the entire pod turning a uniform green color. This color change is due to the heat-sensitivity of the anthocyanin pigments responsible for the purple streaks.
The mature beans, which are shelled from the dried pods, are used like other dried beans in soups, stews, and side dishes. They can be stored for long periods and require soaking and longer cooking times to become tender. The young pods also hold up well to pickling, which helps preserve their flavor and color.
Common Namesakes and Confusions
The evocative name “Dragon Tongue” is not exclusive to this edible bean, leading to confusion with several other ornamental plants. The most common namesake is the plant Hemigraphis repanda, often sold as a houseplant or a terrarium accent. This non-edible species is commonly known as Dragon’s Tongue or Red Ivy, and features thin, ruffled leaves that are green on top and vibrant purple underneath.
Another instance of the name appears in certain succulent or foliage plants, sometimes associated with varieties of Dracaena trifasciata (formerly Sansevieria). While these plants share the dramatic name, their biological classification and uses are entirely separate from the edible bean. These ornamental Dragon’s Tongue plants are purely decorative and are not intended for human or animal consumption.