Soybean was highly valued in the Far East, especially in ancient Chinese civilizations. Even during the Chou dynasty in China, soybean; It is considered one of the 5 sacred grains, along with rye, wheat, millet and rice. Brass Ottoman also existed only recently. There was no rice as in the movies, bulgur vaccine was consumed.
Soy was originally cultivated as a Nitrogen source to contribute to the development of other plants, but the consumption of Soy has also occurred because the plants coincided in times of distress and famine.
It was possible in the late Chou dynasty (1134 – 246 BC) only after the invention of fermentation techniques, but it still never became the main food. As you can see, the soybean plant is a very old plant.