What are the main varieties of black beans? Are all black-colored beans considered black beans?

　　Black beans are the dark-colored seeds of the soybean plant, and together with black fungus, black sesame, black rice, and black jujubes, they are known as the “Five Blacks” in the food world. Rich in nutrients, black beans contain protein, fats, vitamins, trace elements, and more, making them a common grain‑type food that is widely popular among consumers. So, where do black beans come from, and what are the main varieties? Let’s find out.

　　Where is black bean produced?

　　Black beans exhibit strong stress resistance and adaptability, which accounts for their widespread distribution across China. However, when it comes to high-quality black beans, their production is concentrated in regions such as Jiangsu, Shaanxi, Heilongjiang, and Shanxi. In these areas, the beans are not only large in size but also boast high yields and superior nutritional value.

　　What are the main varieties of black beans?

　　After the black bean skins are removed, they can be broadly classified into two types based on the color of the seed kernel: green‑seeded black beans and yellow‑seeded black beans. Green‑seeded black beans, also known as “black‑skinned green‑seeded beans” or “green‑heart black beans,” get their name from their jet‑black outer skin and the greenish hue of the inner seed. Within this category, there are two subtypes—large black beans and small black beans—both round in shape but varying somewhat in size. Yellow‑seeded black beans, also called “black‑skinned yellow‑seeded beans” or “yellow‑heart black beans,” are a small‑grained variety introduced from Japan; they have a slightly flattened form, with an overall outline that is oblong and somewhat compressed.

　　Are black-colored beans the same as black beans?

　　Not all black beans are called black beans. For example, black kidney beans are also legumes, but they are a different species from black beans and do not share the same health benefits. At present, they are primarily used as food. Unless you examine the hilum, the two look very similar, making them difficult to distinguish.

　　In general, black beans exhibit a variety of traits, but their hilums are always linear. By contrast, the hilum of black kidney beans is oval-shaped, slightly depressed, and bears raised dots along its margin. In addition, black beans can be further classified into black soybeans and black adzuki beans. The main differences between them are:

　　1. Color: Black soybeans are typically black, with a uniformly dark surface that exhibits a slight sheen, while the interior is green or bluish-green. In contrast, black adzuki beans are also black, but their surfaces usually bear white or yellow specks, rather than being entirely black, and they display a distinct luster.

　　2. Shape: Black soybeans are typically round and about the same size as yellow soybeans, whereas black adzuki beans are generally oval-shaped and noticeably smaller than large black soybeans.

　　3. Texture: Black soybeans are relatively firm; after cooking, they have a slightly powdery texture and a mild flavor—neither sweet nor bitter. Black adzuki beans are also quite firm; once cooked, they become pleasantly soft and sticky, with a delicate, fragrant aroma.

　　Overall, black beans are highly nutritious and enjoy strong market demand, which is why they are widely cultivated in China. However, it’s important to note that not all black‑colored beans are true black beans, and some dyed black beans are also available on the market; be sure to distinguish between them when making your selection.