Okara is soy pulp made by straining mushed soy beans, and is a byproduct of making tofu bean curd. The color is normally whitish or yellowish. It contains lots of dietary fiber, and is cooked when it is eaten.
Since it is a lees after the soy milk is strained, the price is very cheap. In some cases, tofu makers give it away for free, but was often thrown away in the Edo period (1603-1867). Nowadays, the demand is a lot lower than the supply, and it deteriorates quickly, so it is often used for feeding farm animals. When it is supplied in the market, it is often dehydrated and dried, so the preservability will be kept high.
The most popular way to eat okara is by boiling with ingredients such as fried tofu, shiitake mushroom, and carrot, and add sweet flavor with soup stock, soy sauce, and sugar. This type of dish is called unohana, and has a sweetness of okara and a unique flavor.
It is also used for vegetarian food, instead of using meat for dishes such as hamburg steak, fried food, and stuffed peppers. The important thing is to dehydrate okara well, so it will be solid when it is cooked. Using okara also helps to reduce calorie.
Recently, okara is drawing attention because it contains high dietary fiber, and is used for making cakes and cookies.There is also an example that it was able to make miso fermented soy bean paste by using okara as an ingredient.