Red bean can refer to any of the following: adzuki bean (vigna angularis), kidney bean (red variety of Phaseolus vulgaris), or Vigna umbellata, a kind of legume that has red seeds. Let us talk about the red bean known as the adzuki bean.
The adzuki bean is an annual, green, bushy, erect, and sparsely pilose herb with bright yellow flowers that can reach 90 centimeters in height. The adzuki bean is an annual vine that produces red or brownish beans. The adzuki bean is widely cultivated in different East Asian countries. While the adzuki bean is generally red, there are cultivars of white, black, gray, and mottled varieties.
The domestication of the adzuki bean happened approximately during 3000 BC; where it happened exactly, no one knows. The intelligent guess of scientists who are experts in this field is that it happened somewhere in East Asia, and it is possible that multiple domestications occurred as well. There was a noticeable transformation that happened to the adzuki bean when cultivation began. There were fewer beans but the pods grew longer. There were fewer seeds too, but the seeds grew larger. Cultivated adzuki bean plants were also shorter compared to wild plants.
Species: V. angularis
Binomial name: Vigna angularis
(Willd.) Ohwi & H. Ohashi
Red Bean Trivia
- The Adzuki bean or red bean is also known by other names like aduki bean and red mung bean.
- Scientists believe that the progenitor of the red bean or Adzuki bean is Vigna angularis var. Nipponensis.
- The adzuki bean was one of the first crops subjected to scientific plant breeding in Japan.
- Japan considers the adzuki bean as the second most important legume after soybeans.
Red Bean Buying Guide
You can buy adzuki beans in groceries, supermarkets, or Asian specialty stores. Check the product and packaging. Check the best before or expiry date. If this is unavailable to you in your location, you can order it online.
Red Bean Production & Farming in Texas
To ensure the optimal growth of adzuki bean plants, it is ideal that they are grown somewhere with a temperature ranging from 15 °C to 30 °C and annual rainfall that ranges from 500–1750 mm. Soil temperatures should be above 6-10 °C (30°-34 °C is optimal) since this plant is not frost-hardy. It is drought-hardy though, but the drawback is a reduction in yield. It requires well-draining soil with a pH level ranging from 5 to 7.5 and the need for fertilizer depends on several considerations. Adzuki bean is often grown in intercrops with maize, sorghum, and millet (China).
There is no large-scale commercial production of adzuki beans in Texas. Adzuki beans grow in warm climates, and this can be grown in Texas. In the US, adzuki beans are commonly grown in Michigan, Idaho, and Washington.
Adzuki pod worms, Japanese butterbur borer, and cutworms are the common pests that attack adzuki bean plants.
- Adzuki pod worm – Use pyrethroid insecticides like cyfluthrin and Lambda cyhalothrin.
- Japanese butterbur borer – Use contact insecticides to prevent infestation. Pyrethroids including bifenthrin and permethrin are effective against borers.
- Cutworms – Pesticides such as carbaryl will kill cutworms attacking your adzuki bean plant. Pyrethroid insecticides like cyfluthrin and the insecticide permethrin are also useful for this purpose.
The ancestor of the adzuki bean grew in several countries like Japan, Korea, China, Nepal, and Bhutan. Cultivars resulting from plant breeding of the adzuki bean are being used in China, Japan, Taiwan, and Korea, and they are also considered as the world’s top adzuki bean producers. The high consumption of adzuki bean in Japan explains why the country is a major importer of adzuki bean, importing not just from neighboring Asian countries like China, Thailand, Taiwan, and Korea, but outside Asia as well. Canada and the US export adzuki bean to Japan. In Japan alone, there are more than 300 registered cultivars of adzuki beans. In China, the adzuki bean is called xiǎodòu in Chinese botanical parlance but is commonly called hóngdòu or chìdòu. In Korea, this is called pat. In Vietnam, this is called đậu đỏ. In India, they call this red chori, ravaa’n in Punjabi, and lal chavali in Marathi. In Iraq, this is called lūbyā ḥamrā.
Adzuki beans are sold in sealed (even vacuum-sealed) or resealable plastic or other food-grade packaging. You can also find them sold in cans or a carton box. Packaging includes a label that indicates important information about the product that consumers should know (i.e. manufacturer, country of origin, dietary information, etc).
Enjoying Red Beans
It is common practice to eat sprouted adzuki beans. On their own, adzuki beans have a mild, nutty taste and soft texture. Every 15th of November when Japan celebrates Shichi-Go-San (a traditional rite of passage and festival day in Japan for three- and seven-year-old girls and five-year-old boys), part of the tradition is to eat sekihan – Japanese sticky rice and adzuki beans. Adzuki beans are subjected to soaking, sprouting, or fermenting before you eat them.
Dried adzuki beans should be stored in an airtight container or jar with a lid. Cooked adzuki beans, on the other hand, can be stored in the refrigerator. They will remain in good, stable, edible condition for three days. If these are stored in the freezer, they will keep for as long as six months.
A common way of eating adzuki beans in East Asia is boiling it with sugar and making a red bean paste called anko and then add other flavors like chestnut. The red bean paste is a staple in many dishes, including tangyuan, zongzi, mooncakes, baozi, and red bean ice (Chinese cuisine); anpan, dorayaki, imagawayaki, manjū, monaka, anmitsu, taiyaki, and daifuku (Japanese cuisine). It is also common to find pastries, waffles, biscuits, and baked buns filled or topped with red bean paste. Even ice cream is made using adzuki beans.
A diet consisting of adzuki beans offers the body carbohydrates, dietary fiber, protein, B vitamin folate, several dietary minerals like manganese and phosphorus, and antioxidants. The adzuki bean is one of the most antioxidant-rich foods available. Eating adzuki beans is ideal for people seeking to lose weight or have digestive problems. Adzuki beans also help lower the risk of type 2 diabetes and heart disease.