Chow Line: Green beans aren’t quite beans

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This year we have an overabundance of green beans from our garden. If we eat them with rice, will they make a complete protein like other beans do?

Green beans aren’t really “beans,” at least according to the U.S. Dietary Guidelines. They’re great vegetables, though.

The primary difference is in protein content. A cup of green beans contains just 2 grams of protein, whereas a cup of, say, black beans contains 15 grams of protein. Green beans are actually harvested before the bean in the pod has fully matured — that’s why they don’t have as much protein as black beans, kidney beans or other types of dry beans.

Dry beans are a unique food in the U.S. Dietary Guidelines for Americans. They can be counted as vegetables or as proteins, and, paired with grains such as rice, provide all of the necessary amino acids for a complete protein. Green beans aren’t in the same category, but still are a perfectly fine food to include in the diet.

A cup of green beans has just 35 calories, and is a very good source of fiber, vitamin A, vitamin C, vitamin K, folate, iron and manganese.

An easy way to preserve your bounty is to freeze green beans. Ohio State University Extension recently developed a five-minute video showing how to properly prepare fresh green beans for freezing. It’s online at

One step not to skip is blanching. Although blanching causes some nutrient loss, especially of vitamin C, it prevents loss of other nutrients such as carotenoids.

After washing and trimming green beans, blanching the beans in boiling water for 3 minutes or steaming them for 5 minutes will not only eliminate any surface microorganisms, but will retard enzymes that otherwise would allow the vegetables to continue ripening, thus losing flavor, texture, color or nutrients. After blanching, cool the green beans rapidly in cold water or ice water to immediately stop the cooking process for the highest quality frozen green beans. For more information on freezing green beans and other vegetables, see the OSU Extension fact sheet Freezing Vegetables, at

For information on green bean nutrition and some healthy recipes, OSU Extension offers two additional resources:

• Maximize Your Nutrients from Green Beans and Pea Pods, online at Extension’s Farm to Health Series website at

• Garden to Plate: Green Beans, a 2.5-minute video, online at

Chow Line is a service of Ohio State University’s College of Food, Agricultural, and Environmental Sciences and its outreach and research arms, Ohio State University Extension and the Ohio Agricultural Research and Development Center. Send questions to Chow Line, c/o Martha Filipic, 2021 Coffey Road, Columbus, OH, 43210-1043, or

Editor: This column was reviewed by Dan Remley, field specialist in Food, Nutrition and Wellness for Ohio State University Extension, the outreach arm of the College of Food, Agricultural, and Environmental Sciences.

For a PDF of this column, please click here.

CFAES News Team
For more information, contact: 

Dan Remley
OSU Extension, Food, Nutrition and Wellness