Planting, Harvesting and Distribution

Planting
The process begins in the field with the soybean seed planted as early as April 15th or as late as July 15th. Planting dates vary depending on the latitude and geographic region. Classification of soybean cultivars into maturity groups help U.S. farmers choose correct varieties for their regions. Farmers may plant 6 to 10 different varieties of soybeans each growing season. Seeds develop in pods with each pod containing 1-5 seeds, but the most common varieties contain 2-3 seeds per pod.

Harvesting
Soybeans are considered dry mature when seed moisture reduces to less than 14% in the field. Harvesting date depends on the variety, growing regions, planting date, and local weather conditions. The most active harvest periods are during the months of October and November. In the United States, almost all soybeans are harvested by combines. The seeds are threshed out from pods into a hopper and moved into a transport truck. If moisture content is more than 14%, soybeans need to be dried. Once dried to the appropriate moisture content, seeds are transferred to storage facilities. Proper handling of the soybeans during harvest and storage is critical to protect the beans from damage.

Distribution
Soybeans are stored at farms, elevators, and processing plants in various types of storage facilities before being channeled to the next destination. Local elevators will store and condition the soybeans before selling and shipping to a soybean processor or export elevator. Farmers may also transport soybeans by truck to a regional transport facility such as a railroad or river terminal for shipment directly to a grain buying station, processing plant, or harbor facility
for shipment overseas.

Processing into Products

Once the soybeans are sold to local, national or international processors or crushers, they are processed into various products. Soy processors convert soybeans into products made from whole soybeans, such as tofu, tempeh, miso, natto, soy sauce, some soy flours, soy nuts, and soymilk. Other soybeans destined for more traditional food and technical products are graded, cleaned, dried, and cracked to remove the hull. Soybean hulls are further processed for animal feed or fiber additives for breads, cereals, and snacks.

Processors convert the remaining part of the soybeans, after the hulls are removed, into full-fat flakes that may be used in animal feed or processed into full-fat flour for a variety of commercial food uses. Immersing the full-fat flakes into a solvent bath extracts the crude soybean oil that is then degummed to separate lecithin from the oil. Lecithin is an emulsifying agent and when further processed is used in baked goods, dairy products, and instant foods. The extracted soybean oil, referred to as refined soybean oil is used to produce cooking oil, margarine, and shortening.

After the oil is extracted, the solvent is removed and recycled and the flakes are dried, creating an essentially oil-free, high protein product known as defatted soy flakes. Defatted soy flakes are ground into soybean meal and used to produce feed for animals, primarily poultry, swine, cattle, and aquaculture.

The defatted soy flakes are also the basis of a variety of soy protein products including soy flour, soy concentrates, and soy isolates. Soy flour is produced by grinding and screening defatted flakes. Soy flour adds protein, improves crust color, and increases the shelf life of products of baked goods. Soy concentrates, used in protein drinks, soup bases, and gravies contain about 70 percent protein and retain most of the soybean's dietary fiber. Soy isolates, which yield at least 90 percent protein with little moisture, add texture to meat products and are used for their emulsifying qualities in many dairy-like products including cheese, milk, nondairy frozen desserts, and coffee whiteners. Isolates are also the primary protein sources in a variety of dietary beverages.

View a soybean processing diagram