It is a staple in the diet of people and animals in numerous parts of the world today. Because soybeans contain no starch, they are a good source of protein for diabetics. In East Asia the bean is extensively consumed in the forms of soybean milk, a whitish liquid suspension, and tofu, a curd somewhat resembling cottage cheese. Soybeans are also sprouted for use as a salad ingredient or as a vegetable and may be eaten roasted as a snack food. The self-fertilizing flowers are white or a shade of purple.
Seeds can be yellow, green, brown, black, or bicoloured.
In the United States, commercial varieties have brown or tan seeds, with one to four seeds per pod. The soybean may be cultivated in most types of soil, but it thrives in warm, fertile, well-drained, sandy loam. The crop is planted after all danger of frost is past. Maturing during September and October, soybeans are usually harvested mechanically in the United States, after the leaves have fallen off the plant and the moisture content of the seed has dropped to 13 percent, permitting safe storage. In the 1980s the United States was the world's principal producer, followed by Brazil and China.