Wikipedia
Dougan
Dougan (Chinese: 豆干) is a firm variety of doufu which is popular in China. It differs from regular doufu in that it is firm whereas doufu is soft.
It is composed of two syllables. Dou , and gan . Dou means bean, and gan means dry. This is different from doufu (which also has two syllables), but the second syllable in doufu is "fu" .
It is important to distinguish between doufu and dougan, as it may not be appropriate to substitute doufu for dougan in recipes which call for dougan.
Dougan has less moisture content than doufu in that it is drier, meaning it is less wet. By weight, dougan has a greater bean to water ratio than doufu, meaning that it contains more protein per gram, as the water density is less.