French beans, green beans, string beans and snap beans, are actually different names of the same bean scientifically known as Phaseolus vulgaris. The beans are made up of a green pod with tiny seeds inside and range in size from four to six inches. The pod and the seeds inside are consumed as a single unit. The term “string bean” was born out of the customary preparation exercise of eradicating a string like fibre from the pod before cooking. However, the new varieties of the vegetable no longer have the strings and the only preparation needed is to snap off the ends.
There are two chief subdivisions of green beans known as bush and pole beans. Bush beans develop on short plants that reach the height of roughly two feet and do not require any support. They tend to attain maturity and produce fruit in a fairly short period of time, and then cease fruit production. Due to this, more than a single crop of bush beans can be cultivated in a season. Pole beans grow on plants that grow much taller and require support of poles, hence the name.
There are more than 130 varieties of green beans. Typically used varieties are usually selected for their flavour, succulence and pods and are frequently grown in home gardens. Pod colour can range from green to purple, red or streaked. Even the pod shapes show variation from thin strips like “fillet” to wider “romano” styles and a whole range in between.
History of Green Beans
The green bean originates in Central and South America and was domesticated in ancient times. Seeds of the cultivated varieties have been found in deposits in Peru. Columbus introduced the green bean to the Mediterranean upon return from his second voyage to the New World in 1493. By the seventeenth century, the green bean was cultivated widely in Italy, Greece and Turkey. The largest producers of green beans today are Argentina, Egypt, China, France, India, Indonesia, Italy, Iraq, Spain, Mexico, Netherlands and U.S.A.
A classic American comfort food, the green bean casserole is a staple dish at Thanksgiving dinners. The casserole was the brain child of Dorcas Reilly of Campbell Soup Company, who wanted to ensure that her cream of mushroom soup kept selling. She came up with the quick to make dish with ingredients that would be easily available in most American homes, and the dish was born. Requiring only a few ingredients and easily adjustable to varying tastes, the dish is very easy to make. The original green bean casserole recipe belonging to Dorcas Reilly now sits in the National Inventors Hall of Fame on a yellowing 8 X 11 recipe card along with Thomas Edison’s light bulb.
Health Benefits of Green Beans
Green Beans are loaded with dietary fibre, nearly 9% in each 100 gram serving. The fibre behaves like a laxative, protecting the mucous membrane of the large intestine by minimizing the exposure to toxic substances and binding with cancerous chemicals in the colon. Additionally it aids in lowering bad cholesterol in the body. People afflicted with diabetes can also benefit from green beans as fibre helps to regulate blood sugar levels.
The high levels of vitamin A in green beans, along with flavonoid poly-phenolic antioxidants like zea-xanthin, lutein and ß-carotene together act as scavengers of oxygen-derived free radicals. This helps to protect against heart disease, cholesterol and cancer. The vitamin A also postpones premature ageing by reducing wrinkles, dark spots, and fine lines. The Zea-xanthin in green beans is absorbed by the retinal macula in the eyes and provides UV filtering functions as well as antioxidant activity. Hence green beans offer protection against the age related macular disease (ARMD) in the aged.
In case of injury, the vitamin K helps the body to heal faster by hastening the process of blood clotting. It also allows for more calcium to be absorbed by the body which promotes bone health and density. This reduces the chances of developing osteoporosis. Additionally it is beneficial to women with iron deficiencies. Vitamin C also aids in healing wounds and might have a role in cancer prevention. The antioxidant characteristics of vitamin C protect cellular DNA from damage. The manganese in green beans, besides lessening the symptoms of osteoporosis also helps other nutrients to be absorbed by the body. The significant amounts of silicon in green beans reinforce connective tissue and bone health.
It is a misconception that green beans do not provide sufficient amounts of pigments like carotenoids. Recent studies indicate that lutein, beta-carotene, violaxanthin, and neoxanthin which tomatoes and carrots are so well recognized for are also present in green beans. In fact their quantities are comparable1.
Nutritional Value of Green Beans
Green beans can be consumed in a variety of ways but to get the maximum nutritional benefits, cook them only lightly. Over cooking green beans diminishes some of their nutritional value, especially vitamin C and minerals. While a one hundred gram serving of cooked green beans and raw beans have the same amount of protein, B vitamins, as well as vitamins A and E, cooking wastes approximately thirty percent of the iron, potassium and magnesium and twenty percent of vitamin C.
A one hundred gram serving of raw green beans provide only 31 calories, roughly 7 grams of carbohydrates, 3 grams dietary fibre and 2 grams protein. It contains less than a quarter gram of fat. In the vitamin department the one hundred gram serving delivers 15% vitamin C, 14% vitamin K, 11% vitamin B6, 9% vitamin B2, 8% folate, 7% vitamin B1, 5% vitamins B3 and B5 and 4% vitamin A.
Green beans also contain a good range of some important minerals. A one hundred gram serving delivers 10% of the daily recommended allowance of manganese (based on a 2000 calorie diet), 8% iron, 7% magnesium, 5% phosphorus, 4% each of potassium and calcium, 3% zinc and trace amounts of fluoride.
Uses of Green Beans
While over cooking does destroy some of the nutrients in green beans, steaming for five minutes does no harm. Cooked in this way, they retain their crispness along with most of their nutrients. If frozen initially and then steamed as described, green beans still retain most of their nutrients. Canned green beans lose roughly one third of their phenolic compounds in the canning process, along with some vital B vitamins.
Some quick ideas for using green beans include:
- Throw a handful into stir fries.
- Add to curries and soups.
- Sauté with mushrooms.
- Throw together some raw green beans with a clove of ground garlic, some olive oil, feta cheese and slivered almonds for a great tasting side dish.
- They go well in grilled-salads.
Snap Crackle Green Beans
Ingredients:
- ½ kg green beans
- 1/4 cup buttermilk
- 1/2 cup flour
- 1/4 cup cornmeal
- 1 tsp. baking powder
- 2 tsp. salt plus more for sprinkling
- 1/4 tsp. cayenne (optional)
- Oil for frying
Preparation
- Wash and totally dry the green beans. Place them in a bowl and add the buttermilk to just coat them.
- Combine flour, cornmeal, baking powder, salt, and cayenne in a large bowl. Drain the extra buttermilk, and add the green beans to the flour mixture, coat well.
- Heat about 1/2 inch of oil well over medium heat in a wide, heavy pot.
- Shake the extra flour mixture off the beans and add so there is a single layer in the frying pot. Fry until beans are tender and reach a golden to medium brown colour.
Clinical Trials
According to recent studies the nutritional value of green beans has be highlighted even more. When compared to other foods in the bean family, green beans were found to come out on top. It is now confirmed that in addition to antioxidants like flavonoids quercetin and kaemferol they also contain catechins, epicatechins, and procyanidins. Green beans also contain carotenoids like lutein, beta-carotene, violaxanthin, and neoxanthin.
In a study conducted over six years, researchers found diets rich in green and yellow vegetables slow the development of atherosclerosis, which means it might lead to lowering the risk of coronary heart disease. In the study, mice were divided into two groups, one being fed a diet without vegetables and the other group was given a blend of green vegetables including green beans for 16 weeks. It was found that aortic atherosclerosis was lowered by 38%.