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"What is a legume?"

Dear Anne and Sue,

It's bugging me because I keep hearing the word. What is a legume?

—From Joe


Still have more questions? You'll find more answers in our archived monthly feature articles by the Inquisitive Cooks.

(Meet the Inquisitive Cooks)

Dear Joe,

It's a good question because the word is out there, but it's not often defined. So here goes! A legume is a collection of a particular family of vegetables called Leguminosae. The term includes all peas, beans, and lentils, plus clover, carob, and licorice. Legumes can be generally described as the protective pod of seeds.

Among vegetable families, legumes are unique because of their ability to fix nitrogen in the soil. As a leguminous plant grows, it supplies sugar to bacteria, which form in the nodules of the plant roots. In turn, the bacteria extract nitrogen from the air and convert it to nitrate-one of the most important nutrients for plant growth. Thus, legumes not only supply us with some fine vegetables, but they also benefit the soil in which they are grown.

With the choice of legumes now available, we can enjoy vegetables such as green peas at various stages of maturity. When very tiny, the immature seed plus its pod (known as the snap pea) is a fine treat. Or by choosing another variety of pea, you can enjoy just the seeds, removed from the pod and briefly cooked. But then again, you can choose to leave the pods on the vine so their sugars are changed to starches as they mature. When dried, and their outer covering removed, the seeds can be stored for later use in hearty winter soups and casseroles.

The seeds of dried legumes are high in a storage form of sugar, called oligosaccharides. As the digestive system of most people cannot break down these sugars, they pass undigested to the large intestine where they're fermented by nonpathogenic intestinal bacteria. The term musical fruit, aptly describes the gassy results! (See the article "Getting a Bang out of Beans").

Anne & Sue



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