Nutritional value and health benefits of green beans

Introduction

Green beans which is commonly referred to as string beans (the string which was once their trade mark) can be found in modern varieties. They belong to the same family as shell beans, black beans and kidney bean; in fact all these beans have the same genius/species name in science – Paseolus Vulgaris.

In the past, beans pods often contained a “string”, a hard fibrous strand running the length of the pod. The first “stringless” bean was bred in 1894 by Calvin Keeney, called the father of stringless bean while working in lepsoy, New York. Most modern varieties do not have strings.

Green beans are slightly varieties in shapes in different areas at cultivation and goes by different names around the world like French bean, string bean even squeaky beans. There are approximately (150) one hundred and fifty varieties throughout the world but despite variables appearance, their nutritional contents and health benefits remain similar.

In most parts of Africa, it is a source of income for both small scale and large scale farmers (commercial are export to oversees market (Europe and preference)) and to canning industries. Market preference for green beans pods differs with regions but most produce in Eastern Africa are round and thin mainly to suit European markets.

Kenya especially have different varieties of green beans that goes with different shades of green namely serengity, Boston, venda, Tana, Balcampo volte, Lamami, Hawail, Moonstone, Picasso.

History of green beans

Green beans like other beans such as kidney beans, navy beans or black beans are known botanically as phaseolu vulgaris. Green bean is originated in Peru, from there, it spread out throughout the south and central parts of America by migrating Indians. They were also introduced into Europe around the 16^th century by Spanish explorers and subsequently were spread through many other parts of the world by Spanish and Portuguese traders.

They are widely cultivated across Asia and Africa widely versatile vegetable that can be cultivated in many different climates. today the largest commercial producers of green beans includes Argentina, Chine, Egypt, France, Indonesia, India, Iraq, Italy, France, Mexico and the United States.

In Africa, green beans are largely cultivated and exported to regional and international market snap or French beans as it is majorly called in Africa is export vegetable crop in Kenya, Tanzania, Uganda, Zambia, Zimbabwe and North Africa with its gaining importance to other countries like, Cameroon, Ethiope, Rwanda and Sudan.

In East central and Northern Africa, production is dominated by ‘Bush’ type of cultivation, but ‘Climbing’ type of cultivation are generation, more productive and have longer harvest periods.

Green beans in Africa are cultivated in warm climates. It is grown in farm with flowers and its pods.

Classification/types of cultivation

Green beans are classified by growth habit into two major group.

1. Bush or dwarf:

They are short plants growing not more than 2 (two) feet’s (61cm) in height, often requiring no support. They generally reach maturity and produce all their fruit in a relatively short period of time, then cease production. Due to this concentrated production and ease of mechanized harvesting, they are mostly grown on commercial farms.

2. Pole or climbing:

These classes have the habit of climbing and produce a twisting vine, which must be supported by pole, trellises or other means. They are commonly referred to as runner or yard long beans.

Varieties

Approximately 150 varieties of green beans are known but 10 varieties are specialized for use as green beans, selected for its succulence and flavour of their pods, usually grown in vegetable gardens. Pods colour can be green, purple, red or streaked varieties are by cultivation types.

Varieties of bush/dwarf green beans

• Blue lake
• Bush Kentucky wonder 69 days (green, 1945 AAS winner)
• Derby (1990 AAS winner)
• Kenyan beans
• Purple teepee (purple pods)
• Burpee’s stringless green pod (green, hair 100m) 50 days.
• Contender (green) 50 days
• Rocdor (yellow) 53 days
• Cherokee wax (yellow) 55 days
• Red swan (red 55 days)
• Maxibel (green fillet) 59 days
• Roma II (green romano) 59 days

Varieties of pole climbing green beans

• Algarve
• Blue lake (green) 60 days.
• Golden gate (yellow/wax)
• Kentucky blue (green) (AAS 1991 winner)
• Old home stead/Kentucky wonder (green hair scarlet runner).
• Navel of Venice (yellow Roman) 54 days
• Rattle snake (streaked hair 100m) 73 days
• Purple king (purple) 75 days.
• Fortex (green fillet) 60 days.

Nutritional value of green beans

With different shades and pod colours, these succulent and flavoured beans have nutritional benefits that are hard to argue with. There beans are harvested while young and tender and are highly nutritious, they are low in calories and fat and contains no cholesterol.

They are excellent source of vitamin K, B₃, C, dietary fibre, folate and daily protein requirement. A good source of calcium for strong bones and healthy teeth, silicon for hair, skin and helps cleanse the system off toxins, parasites and bacteria’s, iron for proper oxygen transport in the body manganese for fertility and bone formation, potassium and copper.

Nutritional value per 100g (3.50z)

Energy                                                       131kg (31kcal)

Carbohydrates                                          6.97g

Dietary fibers                                            2.7g

Fat                                                              0.22g

Protein                                                       1.83g

Vitamins

Vitamin A                                                   351g (4%)

Thiamine (B₁)                                            0.082mg (7%)

Riboflavin (B₂)                                           0.104mg (9%)

Niacin (B₃)                                                 0.734mg (5%)

Pantothenic acid (B₅)                               0.225mg (5%)

Vitamin (B₆)                                               0.141mg (11%)

Folate (B₉)                                                 33µg (8%)

Vitamin C                                                   12.2mg (15%)

Vitamin K                                                   14.4µg (14%)

Minerals

Calcium                                                     37mg (4%)

Iron                                                             1.03mg (8%)

Magnesium                                               25mg (7%)

Manganese                                               0.216mg (10%)

Phosphorus                                              28mg (5%)

Potassium                                                 211g (4%)

Zinc                                                            0.24mg (3%)

Other constituents

Fluoride                                                     19µg

Units:

µg     = micrograms

Mg    = milligrams

IU      = International units

Percentages are approximated using us recommendation for adults.

(Source: USDA Nutrient Database).

Culinary uses

In many countries green beans is popular, especially in American and European dishes. They appear in a wide array of cultural dishes, their nutritional content and health benefits remains similar.

They are grown and eaten around the world, picked young and tender, they are often steamed, stir- fried or baked. They are also eaten raw in salad, or straight from the garden. They are preferably picked young for harmful compounds in them. They are also canned, used in preparing intercontinental dishes.

Preventive uses of green beans

• Helps prevents and flight against cancer; the supports it gives to various areas of the body has the ability to help prevent and stop the spread of various cancers throughout the body. With the high antioxidants contents in green beans nutrition which helps scavenge free radicals in the body that is responsible for many diseases and damages to the system.
• Prevents infections: A number of vitamins like niacin and tramine that are present in green beans are a good source of nutrients that help to prevent many infections in the body.
• Protects your heart from diseases: keeps your heart beating strong, beans helps support heart health by managing metabolic syndrome, a cluster of conditions associated with a higher risk of heart disease, stroke and diabetes, consuming legumes four times or more a week can decrease the risk of heart disease up to 22 percent versus eating once a week.
• Keep bones strong: Because of its high vitamin K content, green beans nutrition can also help your body build and maintain strong bones. From the elderly at risk of osteoporosis to athletes, consuming high levels of vitamin k helps your body maintain bone density, reduce the risk of bone fracture and even helps heal broken bones.

Health benefits of green beans

Cardiovascular disease:

Green beans help reduce risk of heart disease due to their high level of flavonoids. Flavonoid are polyphenolic antioxidants that are commonly found in fruits and vegetables. These antioxidants have certain anti – inflammatory properties. High level of flavonoids intake prevents blood cloths in the arteries and veins. Therefore a healthy volume of green beans in a diet can help prevent heart attack, stroke, and heart disease.

Colon cancer:

Recent studies have shown green beans consumption to be beneficial for preventing pre-cancerous polyps that commonly leads to colon cancer. Studies have shown that increasing dietary green beans intake can reduce the risk of cancerous adenomas recurrence and colorectal cancer. Also the high fiber content positively impact your digestive system. It helps ease digestive process and promotes healthy bowel movement which decreases stress on the intestinal tract.

Diabetes

These power packed legumes have been shown to help manage and regulate diabetes symptoms in many patients certain studies have shown a definitive hypoglycervic influence; green beans and similar plants helps to control or early prevent diabetes.

Immune system

There are far more immune system boosting antioxidants in green beans. They are beneficial compound in the body that seeks out dangerous free radicals and eliminate them from our system before they can cause illness or tissue damage.

Eye health

Specific carotenoids that are found in green beans can prevent muscular degeneration, which is a decrease in vision and eye function. Ensure that these carotenoids level stay strong to prevent vision deterioration is one of the many benefits of including green beans in your balanced diet.

Bone health

There are number of nutrients such as calcium found in green beans that helps in preventing bone deterioration and osteoporosis. They contain vitamin K, A and silicon green beans been a terrific source for silicon which is a key element in bone regeneration and overall bone health.

Gastro intestinal issues:

Green beans are packed with fiber which is a huge beneficial compound in our body. By keeping enough fiber in our diets, we are able to ease certain digestive issue like constipation, hemorrhoids, ulcers, and acids reflux disease. There conditions range from mildly irritant to potentially life threat living and the amount of fiber we consume is a key element in their prevention. Due to the normal serving of green beans which is 100 grams, you can gain 15% of daily recommended amount of fiber.

Pre–natal health:

They are  great source folic acid, which plays a major role – a number of internal process, more importantly in protecting infarcts in the womb folic acids in a woman body  helps in healthy development of foetus in utero, especially In the prevention of neutral tube defects. It ensures a healthy and happy baby by keeping folic acids levels high.

Conclusion

The health benefits of green beans are so enormous and so very important to the health and delicious cruchy vegetable packed with nutritious vitamin, minerals, fiber`s for proper and healthy bowel movement.

If ignores or lack of awareness on its use to promote healthy living considering it’s nutritional value can cause certain deficiencies in an individual like poor eyesight, gastro intestinal issues, poor prenatal health, poor bone structure or health, break down of the immune system which allows dangerous free radicals into the system to cause illness or damage.

The importance and awareness of its benefit is a public health problem and as such effort should be made by health workers and authorities to create more awareness.

References

Adams, M., Golden, D.L. & Chen I. E. (2006). A diet rich in green and yellow vegetables inhibits atherosclerosis in mice. Journal of Nutrition, 136, 1886-1889.

Anthon, G.E. & Barrett, D.M. (2006). Characterization of the temperature activation of pectin methyl esterase in green beans and tomatoes  J. Agric Food Chem, 54(1), 204-11

Baardseth, P., Bjerke, F. & Martinsen, B. K. (2010). Vitamin C, total phenolics and antioxidative activity in tip cut green beans (phaseolus vulgaris) and swede rods (brassica napus var. napobrassica) processed by methods used in catering. J. Sci. Food Agric, 90(7), 1245-55

Blackburn, G.L., Phillip, J.C. & Morreale, S. (2001). Physician’s guide to popular low carbohydrate weight loss diet. Cleve Clin J Med, 68(9), 765-6

EL – Qudah, J. M. (2009). Identification and quantification of major carotenoids in some vegetables. American Journal of Applied Science, 6(3), 592-497.

Luthria, D. L. (2006). Phenolic acid contents of fifteen dry edible beans (phaseolus vulgaris L.) varieties. Journal of Food Composition and Analysis, 19(23), 202-11.

Oomah, B.D., Corb, A. & Balasubramanian, P. (2010). Antioxidant and anti – inflammatory activities of bean (phaseolus vulgaris L.) J Agric. Food Chem, 58 (14), 8225 – 8230.

Rickman, J.C., Barrett, D.M. & Bruhn, C.M. (2007). Nutritional comparison of fresh and canned fruits and vegetables. Part 1 vitamins C and B and phenolic compounds. J Sci Food Agric., 87, 930-944.