|1. Legumes are members of the Fabaceae, or bean family, and include several important food crops: peas, beans, soybeans, and peanuts. The highly nutritious seeds, and occasionally the pods, of legumes have become a food source second only to the cereals. In terms of nutritional quality, legumes are excellent sources of protein and, in many cases, oil.
2. The high protein content of many legumes is due to their association with nitrogen-fixing bacteria in their roots. Nitrogen fixation converts the unusable N2 gas into ammonium (NH41), which the plants can incorporate in the synthesizing of proteins.
3. Dozens of types of peas and beans are valued for their high protein content.
4. The peanut (Arachis hypogea) has a South American origin and is unusual in that the plant itself “plants” its seed pods in the soil. The peanut is valued for both its oil and its protein content. George Washington Carver was single-handedly responsible for developing the peanut as a major crop in the post–Civil War South.
5. The protein content of soybean (Glycine max) is one of the highest of all crops. The soybean has a long history of use in the Orient, where it has been modified by various treatments, making it an extremely versatile food.
6. Legumes are also valued as forage crops and as “green manure” to enhance soil fertility.
7. The search for new crops has uncovered several relatively unknown legumes, such as the winged bean, jicama, and groundnut, that may become the new Cinderella crops in the future.