Edamame, in general, is soy beans (soya beans) harvested before the completely matured.
Because they are harvested with "stems" (Eda in Japanese), they are called "edamame", which literally means soy beans with stems. They are roughly 3 types: 1. Ao-mame, 2. Cha-mame, and 3. Kuro-mame.
What types of Edamame are there?
1. Ao-mame (Green Beans)
This is the most commonly recognized type; edamame in green colour. The main place of origin is Chiba, Hokkaido. But thesedays, it is grown in all over the place. The taste is simple and refreshing.
2. Cha-mame (Brown beans)
This is the type with the great flavor and richness of soy itself. It is the edamame with slightly brown shell and / or brown fuzz on the surface of the shell. They are mainly grown in northern part of Japan from Kanto area up to Tohoku.
3. Kuro-mame (Black beans)
Kuromame is literally the black beans. The same type that you usually see in Osechi dish in New Year. This type of edamame is mainly grown in Tanba, Hyogo prefecture. The flesh is large in size. The taste and flavor are beyond description. It is pity the shipping period is very limited.
Why Fresh (raw) Edamame with shell is better than Frozen edamame?
Fresh Edamame tastes way better than frozen:
While most of the frozen edamame in the market is from China, Thailand, or Taiwan, it tastes more "watery" and less "umami" taste than fresh edamame. Although it takes more effort to prepare, the freshly boiled edamame tastes much better and the difference is obvious.
Is Edamame healthy?
Also known as "farm's meat", it contains much nutrition; mainly protein but also dietary fibre, Vitamin B1, B2, folic acid, iron, and potassium. People may wonder if it contains too much sugar, it only contains 1/3 of what's contained in boiled sweet corn or broad beans.