Soybean
Overview
Soybean (scientific name: Glycine max) is an annual herbaceous plant belonging to the Fabaceae family and also refers to its seed. It is believed to have originated in East Asia, and as one of the crops cultivated by humans for the longest time, it contains large amounts of both protein and fat, so it is widely used as food, feed, and industrial raw material. Today, soybean is an internationally traded commodity that has characteristics of both grain and oilseed, and it is also a representative product with high price volatility in the global agricultural market.
Main Content
Botanical Characteristics
Soybean grows upright or vining, and its height reaches 30 cm to 150 cm depending on the variety. The leaves are trifoliate compound leaves, and the flowers are purple or white papilionaceous (butterfly-shaped). In the roots, rhizobia live symbiotically and fix atmospheric nitrogen; thanks to this, soybean grows well even in poor soil and is used as a rotational crop that increases soil fertility. Seeds are contained 2–4 per pod, and according to seed coat color they are divided into yellow soybean, black soybean, green soybean, brown soybean, etc.
History and Spread
The view that soybean cultivation originated in northern China is most widely accepted, and traces of cultivation have been confirmed from around 3000 BCE. It was introduced to the Korean Peninsula before the Three Kingdoms period and became the foundation of fermented and processed food culture such as doenjang (soybean paste), ganjang (soy sauce), and tofu. After the 18th century it spread to Europe and the Americas, and in the 20th century, as large-scale mechanized cultivation began in the U.S. Midwest, it became established as a global crop.
Nutritional Value
Soybean has a protein content of about 35–40%, 2–3 times higher than grains, and contains 15–20% fat and around 30% carbohydrates. It is rich in the essential amino acid lysine but low in methionine, so when consumed together with grains, protein efficiency increases. It is also rich in functional components such as isoflavones, saponins, lecithin, oligosaccharides, and dietary fiber. However, antinutritional factors such as trypsin inhibitors and phytic acid must be removed by sufficient heating.
Varieties and Processed Products
Depending on use, they are classified into edible soybean, soybean for jang, tofu soybean, soybean sprout soybean, and feed soybean. Representative processed products include tofu, soy milk, doenjang, ganjang, gochujang, cheonggukjang, soybean oil, and soybean flour; outside East Asia, Japan's natto and miso and Indonesia's tempeh are famous. The soybean meal left after oil extraction is a key protein source for livestock feed.
Industrial Uses
Soybean oil is used not only for food but also as a raw material for biodiesel, printing ink, paints, and lubricants, and soybean protein is also used in food additives and biodegradable plastic materials. Recently, high-purity protein isolate extracted from soybean has attracted attention as a main ingredient in meat substitute products.
Cultivation and Production
Soybean is a summer crop and matures 90–140 days after sowing. Thanks to the nitrogen-fixing ability characteristic of legumes, it contributes to soil management in rotation systems with corn and wheat. Global production exceeds 350 million tons per year, and Brazil, the United States, Argentina, and China account for more than 80% of the total. In Korea, the self-sufficiency rate for edible soybean remains around 30%, and it relies on imports for a considerable amount.
Recent Trends
In 2024–2025, the soybean market is being greatly shaken by climate variability and trade policy. Brazil has continued to set production records due to expanded planting area and increased yields, solidifying its position as the largest exporter, while the United States has been exposed to export uncertainty due to China's import diversification and changes in tariff policy. Abnormal weather such as droughts and floods in growing regions is increasing crop variability and causing sharp fluctuations in international soybean prices.
On the technological side, the share of genetically modified (GM) soybean cultivation continues to expand, centered on South America, while development of high-oleic and low-allergen soybeans based on gene editing (CRISPR) is active. In consumption trends, while growth in the plant-based protein and meat substitute markets is experiencing slowdown and reorganization, soybean-derived protein made through precision fermentation and soy milk-based fermented beverages are emerging as new growth axes. Domestically, policies are being pursued to expand paddy-field soybean cultivation to raise soybean self-sufficiency, develop climate-responsive varieties, and foster regionally specialized soybean industries.
Related Topics
- [[Tofu]]
- [[Doenjang]]
- [[Meat substitute]]
- [[Agriculture]]
- [[Plant-based protein]]